<PAGE>


                                                                    Exhibit 10.6


                           PURCHASE AND SALE AGREEMENT
                             AND ESCROW INSTRUCTIONS


         THIS PURCHASE AND SALE AGREEMENT AND ESCROW INSTRUCTIONS (this
"AGREEMENT") is made as of November 30, 1999 (the "EFFECTIVE DATE"), by QUIDEL
CORPORATION, a Delaware corporation, with a principal executive office at 10165
McKellar Court, San Diego, California 92121 ("SELLER"), and 10165 MCKELLAR
COURT, L.P., a California limited partnership, with a principal executive office
at 11440 W. Bernardo Court, Suite 280, San Diego, California 92127
("PURCHASER").


                              W I T N E S S E T H:

                                   ARTICLE I

                                PURCHASE AND SALE

         SECTION 1.1 AGREEMENT OF PURCHASE AND SALE. Subject to the terms and
conditions hereinafter set forth, Seller agrees to sell and convey to Purchaser,
and Purchaser agrees to purchase from Seller, all of Seller's right, title and
interest in and to the following:

                 (a) that certain tract or parcel of land commonly known as
10165 McKellar Court, San Diego, San Diego County, California, and more
particularly described in EXHIBIT A attached hereto and made a part hereof,
together with all rights and appurtenances pertaining to such property,
including any right, title and interest of Seller in and to relating to such
property, easements, covenants, adjacent streets, alleys or rights-of-way
relating to such property (the property described in clause (a) of this Section
1.1 being herein referred to collectively as the "LAND");

                 (b) the buildings, structures, fixtures and other improvements
affixed to or located on the Land other than those listed in EXHIBIT J attached
hereto (collectively, the "IMPROVEMENTS");

                 (c) any and all of Seller's right, title and interest in and to
all tangible personal property listed on EXHIBIT B attached hereto (the property
described in clause (c) of this Section 1.1 being herein referred to
collectively as the "PERSONAL PROPERTY");

                 (d) any and all of Seller's right, title and interest in and
to: (i) all assignable contracts and agreements (collectively, the "OPERATING
AGREEMENTS") listed and described on EXHIBIT C attached hereto and made a part
hereof, relating to the upkeep, repair, maintenance or operation of the Land,
Improvements or Personal Property; (ii) all assignable existing warranties and
guaranties (express or implied) issued to Seller by any contractor or
manufacturer in connection with the Improvements or the Personal Property; (iii)
all assignable existing permits, licenses, approvals and authorizations issued
by any governmental authority in connection with the Property; and (iv) to the
extent assignable, all trade names and general intangibles relating to the Land
or Improvements listed and described on EXHIBIT D attached hereto (the property


<PAGE>


described in clause (d) of this Section 1.1 being sometimes herein referred to
collectively as the INTANGIBLES").

         SECTION 1.2 PROPERTY DEFINED. The Land and the Improvements are
hereinafter sometimes referred to collectively as (the "REAL PROPERTY"). The
Land, the Improvements, the Personal Property and the Intangibles are
hereinafter sometimes referred to collectively as the "Property."

         SECTION 1.3 PURCHASE PRICE. Seller agrees to sell and Purchaser agrees
to purchase the Property for the amount of Fifteen Million Dollars
($15,000,000.00) (the "PURCHASE PRICE").

         SECTION 1.4 DEPOSIT. On or before two (2) business days after execution
of this Agreement and delivery of a fully executed copy of this Agreement to
Fidelity National Title Company (the "ESCROW AGENT"), having its office at 2763
Camino del Rio South, San Diego, California 92108, Attention: Nancy Kelley,
Purchaser shall deposit with Escrow Agent, the sum of Fifty Thousand Dollars
($50,000.00) in good funds, either by certified bank or cashier's check or by
federal wire transfer. The Escrow Agent shall hold the deposit in an
interest-bearing account reasonably acceptable to Seller and Purchaser, in
accordance with the terms and conditions of this Agreement. All interest on such
sum shall be deemed income of Purchaser, and Purchaser and Seller shall share
equally all costs and fees imposed on the deposit account. The deposit and all
accrued interest (collectively, the "DEPOSIT") shall be distributed in
accordance with the terms of this Agreement.

         SECTION 1.5 PAYMENT OF PURCHASE PRICE. On the business day of the
Closing (as defined in Section 4.1 below) Purchaser shall deposit with Escrow
Agent by cashier's check or wire transfer, a sum equal to the Purchase Price, as
increased or decreased by prorations and adjustments as herein provided PLUS an
amount equal to Purchaser's share of closing costs as provided herein, and LESS
an amount equal to the Deposit.

         SECTION 1.6 DEPOSIT AS LIQUIDATED DAMAGES. FROM AND AFTER THE
EXPIRATION OF THE INSPECTION PERIOD AND THE TITLE INSPECTION PERIOD, AS SUCH
TERMS ARE DEFINED HEREINBELOW (THE "APPROVAL DATE"), IN THE EVENT THE SALE OF
THE PROPERTY AS CONTEMPLATED HEREUNDER IS NOT CONSUMMATED SOLELY BY REASON OF A
DEFAULT UNDER THIS AGREEMENT ON THE PART OF PURCHASER AND SELLER IS READY,
WILLING AND ABLE TO PERFORM ITS OBLIGATIONS UNDER THIS AGREEMENT AND ALL
CONDITIONS PRECEDENT TO CLOSING HAVE BEEN WAIVED OR SATISFIED, THEN THE DEPOSIT
SHALL BE PAID TO AND RETAINED BY SELLER AS LIQUIDATED DAMAGES. THE PARTIES
ACKNOWLEDGE THAT SELLER'S ACTUAL DAMAGES IN THE EVENT THAT THE SALE IS NOT
CONSUMMATED WOULD BE EXTREMELY DIFFICULT OR IMPRACTICABLE TO DETERMINE.
THEREFORE, BY SEPARATELY INITIALLING THIS SECTION 1.6 BELOW, THE PARTIES
ACKNOWLEDGE THAT THE DEPOSIT HAS BEEN AGREED UPON, AFTER NEGOTIATION, AS THE
PARTIES' REASONABLE ESTIMATE OF SELLER'S DAMAGES AND AS SELLER'S EXCLUSIVE
REMEDY AGAINST PURCHASER IN THE EVENT THE CLOSING DOES NOT OCCUR AND AS SELLER'S
SOLE AND EXCLUSIVE REMEDY AGAINST PURCHASER ARISING FROM SUCH FAILURE OF THE
SALE TO CLOSE. IN ADDITION, PURCHASER SHALL PAY



                                      -2-
<PAGE>


ALL TITLE, SURVEY AND ESCROW CANCELLATION CHARGES. NOTWITHSTANDING THE
FOREGOING, IN NO EVENT SHALL THIS SECTION 1.6 LIMIT THE DAMAGES RECOVERABLE BY
EITHER PARTY AGAINST THE OTHER PARTY DUE TO (A) THE OTHER PARTY'S OBLIGATION TO
INDEMNIFY SUCH PARTY, IF ANY, IN ACCORDANCE WITH THIS AGREEMENT, OR (B) THIRD
PARTY CLAIMS. BY THEIR SEPARATELY INITIALING THIS SECTION 1.6 BELOW, PURCHASER
AND SELLER ACKNOWLEDGE THAT THEY HAVE READ AND UNDERSTOOD THE ABOVE PROVISION
COVERING LIQUIDATED DAMAGES, AND THAT EACH PARTY WAS REPRESENTED BY COUNSEL WHO
EXPLAINED THE CONSEQUENCES OF THIS LIQUIDATED DAMAGES PROVISION AT THE TIME THIS
AGREEMENT WAS EXECUTED.

Purchaser's Initials   __________                 Seller's Initials   __________

         SECTION 1.7 ESCROW AGENT. Escrow Agent shall hold and dispose of the
Deposit in accordance with the terms of this Agreement. Seller and Purchaser
agree that the duties of the Escrow Agent hereunder are purely ministerial in
nature and shall be expressly limited to the safekeeping and disposition of the
Deposit in accordance with this Agreement. Escrow Agent shall incur no liability
in connection with the safekeeping or disposition of the Deposit for any reason
other than Escrow Agent's misconduct or negligence. In the event that Escrow
Agent shall be in doubt as to its duties or obligations with regard to the
Deposit, or in the event that Escrow Agent receives conflicting instructions
from Purchaser and Seller with respect to the Deposit, Escrow Agent shall not be
required to disburse the Deposit and may, at its option, continue to hold the
Deposit until both Purchaser and Seller agree as to its disposition, or until a
final judgment is entered by a court of competent jurisdiction directing its
disposition, or Escrow Agent may interplead the Deposit in accordance with the
laws of the state in which the Property is located.

         Escrow Agent shall not be responsible for any interest on the Deposit
except as is actually earned, or for the loss of any interest resulting from the
withdrawal of the Deposit prior to the date interest is posted thereon.

         Escrow Agent shall execute this Agreement solely for the purpose of
being bound by the provisions of Sections 1.4, 1.5, 1.6 and 1.7 hereof.

                                   ARTICLE II

                                      TITLE

         SECTION 2.1 TITLE INSPECTION PERIOD. During the period beginning upon
the Effective Date and ending at 5:00 p.m. (local time at the Property) on the
45th day after the Effective Date (hereinafter referred to as the "TITLE
INSPECTION PERIOD"), Purchaser shall have the right to review: (a) a current
preliminary title report on the Real Property (the "PTR") issued by Fidelity
National Title Company (the "TITLE COMPANY"), accompanied by copies of all
documents referred to in the report; (b) copies of the most recent property tax
bills for the Property; and (c) an ALTA survey of the Real Property prepared by
a licensed surveyor (the "SURVEY"). Item (a) shall be obtained by Purchaser
within five (5) days after the Effective Date. Item (c) shall be obtained by



                                      -3-
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Purchaser within thirty (30) days after the Effective Date. Item (b) shall be
delivered by Seller to Purchaser within five (5) days after the Effective Date.

         SECTION 2.2 TITLE EXAMINATION. Purchaser shall notify Seller in writing
(the "TITLE NOTICE") prior to the expiration of the Title Inspection Period
which exceptions to title (including survey matters), if any, will not be
accepted by Purchaser. If Purchaser fails to notify Seller in writing of its
disapproval of any exceptions to title by the expiration of the Title Inspection
Period, Purchaser shall be deemed to have approved the condition of title to the
Real Property. If Purchaser notifies Seller in writing that Purchaser objects to
any exceptions to title, Seller shall have two (2) business days after receipt
of the Title Notice to notify Purchaser of either of the following: (a) that
Seller will remove such objectionable exceptions from title on or before the
Closing; or (b) that Seller elects not to cause such exceptions to be removed.
If Seller fails to notify Purchaser within such two-business-day period, then
Seller shall be deemed to have made an election under the foregoing clause (b).
Notwithstanding the foregoing or any other provision of this Agreement, all
monetary obligations disclosed in the PTR are to be satisfied by Seller. The
procurement by Seller of a commitment for the issuance of the Title Policy (as
defined in Section 2.5 hereof) or an endorsement thereto insuring Purchaser
against any title exception which was disapproved pursuant to this Section 2.2
shall be deemed a cure by Seller of such disapproval. If Seller gives Purchaser
notice under clause (b) above, Purchaser shall have three (3) business days
after the date of such notice in which to notify Seller that Purchaser will
nevertheless proceed with the purchase in accordance with the provisions of this
Agreement and take title to the Property subject to such exceptions, or that
Purchaser will terminate this Agreement. Purchaser's failure to respond within
such three-business-day period shall be deemed an election to terminate this
Agreement. If, despite Seller's election to eliminate any disapproved exception
under clause (a) above, the exception has not been eliminated on or before the
Closing, Purchaser, at its option and sole discretion, may either: (a) elect in
writing to waive its prior disapproval; (b) if the exception represents a
monetary obligation, instruct Escrow Holder to deduct from Seller's proceeds
hereunder the amount necessary to satisfy the obligation and thereby eliminate
the exception; or (c) treat the failure to eliminate the exception as a failure
of a contingency under this Agreement, in which event the Escrow shall be
cancelled and this Agreement shall be terminated. If this Agreement is
terminated pursuant to the foregoing provisions of this paragraph, then neither
party shall have any further rights or obligations hereunder (except for any
indemnity obligations of either party pursuant to the other provisions of this
Agreement), the Deposit shall be returned to Purchaser and each party shall bear
its own costs incurred hereunder.

         SECTION 2.3 PRE-CLOSING "GAP" TITLE DEFECTS. Purchaser may, at or prior
to Closing, notify Seller in writing (the "GAP NOTICE") of any objections to
title: (a) raised by the Title Company between the expiration of the Title
Inspection Period and the Closing; and (b) not disclosed by the Title Company or
otherwise known to Purchaser prior to the expiration of the Title Inspection
Period; provided that Purchaser must notify Seller of such objection to title
within two (2) business days of being made aware of the existence of such
exception. If Purchaser sends a Gap Notice to Seller, Purchaser and Seller shall
have the same rights and obligations with respect to such notice as apply to a
Title Notice under Section 2.2 hereof; provided, however, in no event shall the
date of Closing be extended beyond December 31, 1999.



                                      -4-
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         SECTION 2.4 PERMITTED EXCEPTIONS. The Property shall be conveyed
subject to the following matters, which are hereinafter referred to as the
"PERMITTED EXCEPTIONS":

                 (a) those matters (including, without limitation, the
exceptions disclosed in the PTR) that either are not objected to in writing
within the time periods provided in Sections 2.2 or 2.3 hereof, or if objected
to in writing by Purchaser, are those which Seller has elected not to remove or
cure, or has been unable to remove or cure, and subject to which Purchaser has
elected or is deemed to have elected to accept the conveyance of the Property;

                 (b) the lien of all ad valorem real estate taxes and
assessments not yet due and payable as of the date of Closing, subject to
adjustment as herein provided;

                 (c) local, state and federal laws, ordinances or governmental
regulations, including but not limited to, building and zoning laws, ordinances
and regulations, now or hereafter in effect relating to the Property;

                 (d) items shown on the Survey and not objected to by Purchaser
or waived or deemed waived by Purchaser in accordance with Section 2.2 or
Section 2.3 hereof;

                 (e) rights of tenants under leases affecting the Property,
including the Lease dated as of the Closing between Seller and Purchaser; and

                 (f) the lien of the deed of trust securing the Loan (as defined
below).

         SECTION 2.5 CONVEYANCE OF TITLE. At Closing, Seller shall convey and
transfer to Purchaser fee simple title to the Land and Improvements, by
execution and delivery of the Deed (as defined in Section 4.2(a) hereof) and
Escrow Agent shall obtain the irrevocable commitment of the Title Company to
issue an ALTA Joint Protection Policy of Title Insurance (the "TITLE POLICY")
covering the Real Property, in the full amount of the Purchase Price, subject
only to the Permitted Exceptions

                                  ARTICLE III

                               REVIEW OF PROPERTY

         SECTION 3.1 RIGHT OF PHYSICAL INSPECTION. During the period beginning
upon the Effective Date and ending at 5:00 p.m. (local time at the Property) on
December 20, 1999 (the "INSPECTION PERIOD"), Purchaser, its agents, employees,
and independent contractors, shall have the right to make a physical inspection
of the Real Property and perform an environmental assessment on the Property
pursuant to the terms and conditions of this Agreement.

         Purchaser understands and agrees that any on-site inspections or
environmental assessments of the Property shall occur at reasonable times agreed
upon by Seller and Purchaser after reasonable prior written notice to Seller and
shall be conducted so as not to interfere unreasonably with the use of the
Property by Seller. Seller reserves the right to have a representative present
during any such inspections. Purchaser shall promptly restore the Real Property
to its prior condition following any such inspections or assessments, at
Purchaser's sole cost and expense. At Seller's option, Purchaser will furnish to
Seller copies of any reports



                                      -5-
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received by Purchaser relating to any inspections of the Property. Purchaser
agrees to protect, indemnify, defend and hold Seller harmless from and against
any claim for liabilities, losses, costs, expenses (including reasonable
attorneys fees), damages or injuries arising out of or resulting from the
inspection of the Property by Purchaser or its agents or consultants, and
notwithstanding anything to the contrary in this Agreement, such obligation to
indemnify, defend and hold harmless shall survive Closing or any termination of
this Agreement.

         SECTION 3.2 DOCUMENT INSPECTION. Seller shall make available (and copy
if requested) all of the following to Purchaser within ten (10) days after the
Effective Date to the extent that such items are in the possession of Seller or
are reasonably obtainable by Seller:

                 (a) copies of any environmental reports relating to the
Property in Seller's possession;

                 (b) a list and complete copies of all Operating Agreements,
including any amendments and other documents pertaining hereto;

                 (c) plans, permits, specifications and certificates of
occupancy for the Real Property;

                 (d) all other reports, surveys, or other information
(including, without limitation, any notices with respect to the Property
received from any governmental agency) in Seller's possession relating to the
Property;

                 (e) the last 12 months utility bills for the Real Property; and

                 (f) existing insurance policies for the Property.

         SECTION 3.3 RIGHT OF TERMINATION. During the period beginning on the
Effective Date and ending at 5:00 p.m. (local time at the Property) on December
20, 1999 (the "DUE DILIGENCE PERIOD"), if for any reason Purchaser, in its sole
discretion, determines that the Property or any aspect thereof is unsuitable for
Purchaser's acquisition, Purchaser shall have the right to terminate this
Agreement by giving written notice thereof to Seller, and if Purchaser gives
such notice of termination, this Agreement shall terminate. If this Agreement is
terminated pursuant to the foregoing provisions of this paragraph, then neither
party shall have any further rights or obligations hereunder (except for any
indemnity obligations of either party pursuant to the other provisions of this
Agreement), the Deposit shall be immediately returned to Purchaser without any
action being necessary, and each party shall bear its own costs incurred
hereunder. If Purchaser fails to give Seller a notice of termination prior to
the expiration of the Due Diligence Period, Purchaser shall be deemed to have
approved all aspects of the Property (except title and Survey, which shall be
governed by Article II hereof) and to have elected to proceed with the purchase
of the Property pursuant to the terms hereof.



                                      -6-
<PAGE>


                                   ARTICLE IV

                                     CLOSING

         SECTION 4.1 TIME AND PLACE. The consummation of the transaction
contemplated hereby (the "CLOSING") shall be consummated on or before December
31, 1999 through an escrow closing administered by Escrow Agent pursuant to
joint instructions from Seller and Purchaser. At the Closing, Seller and
Purchaser shall perform the obligations set forth in, respectively, Section 4.2
and Section 4.3 hereof, the performance of which obligations shall be concurrent
conditions. The Closing shall be held at the offices of Escrow Agent set forth
in Section 1.4.

         SECTION 4.2 SELLER'S OBLIGATIONS AT CLOSING. On or before two (2) days
before Closing, Seller shall:

                 (a) deliver to Escrow Agent a duly executed grant deed (the
"DEED") in the form attached hereto as EXHIBIT E, conveying the Land and
Improvements;

                 (b) deliver to Purchaser a duly executed bill of sale (the
"BILL OF SALE") in the form attached hereto as EXHIBIT F conveying the Personal
Property;

                 (c) deliver to Purchaser a duly executed assignment and
assumption agreement (the "ASSIGNMENT OF CONTRACTS") in the form attached hereto
as EXHIBIT G assigning Seller's interest in the Operating Agreements and the
other Intangibles, to the extent assignable;

                 (d) deliver such evidence as the Title Company may reasonably
require as to the authority of the person or persons executing documents on
behalf of Seller;

                 (e) deliver to Purchaser a certificate in the form attached
hereto as EXHIBIT H duly executed by Seller stating that Seller is not a
"foreign person" as defined in the Federal Foreign Investment in Real Property
Tax Act of 1980;

                 (f) deliver to Purchaser the Operating Agreements;

                 (g) deliver such affidavits as may be customarily and
reasonably required by the Title Company, in a form reasonably acceptable to
Seller;

                 (h) deliver to Purchaser possession and occupancy of the
Property, subject to the Permitted Exceptions;

                 (i) execute a closing statement acceptable to Seller;

                 (j) deliver such additional documents as shall be reasonably
required to consummate the transaction contemplated by this Agreement; and

                 (k) deliver to Purchaser a lease in the form of EXHIBIT I
attached hereto, duly executed by Seller.



                                      -7-
<PAGE>


         SECTION 4.3 PURCHASER'S OBLIGATIONS AT CLOSING. Except as otherwise
provided, on or before two (2) days before Closing, Purchaser shall:

                 (a) deliver to Seller a duly executed Assignment of Contracts;

                 (b) deliver such evidence as the Title Company may reasonably
require as to the authority of the person or persons executing documents on
behalf of Purchaser;

                 (c) deliver such affidavits as may be customarily and
reasonably required by the Title Company, in a form reasonably acceptable to
Purchaser;

                 (d) execute a closing statement acceptable to Purchaser;

                 (e) deliver such additional documents as shall be reasonably
required to consummate the transaction contemplated by this Agreement; and

                 (f) deliver to Seller a lease in the form of EXHIBIT I attached
hereto, duly executed by Purchaser.

         SECTION 4.4 INTENTIONALLY OMITTED.

         SECTION 4.5 CLOSING COSTS.

                 (a) Seller and Purchaser shall execute such returns,
questionnaires and other documents as shall be required with regard to all
applicable real property transaction taxes imposed by applicable federal, state
or local law or ordinance.

                 (b) Seller shall pay the fees of any counsel representing
Seller in connection with this transaction. Seller shall also pay the following
costs and expenses:

                           (i) one-half of the escrow fee, if any, which may be
charged by the Escrow Agent or Title Company;

                           (ii) any imposed transfer tax, documentary stamp tax
or similar tax which becomes payable by reason of the transfer of the Property
(excluding, however, any sales tax in respect of the Personal Property);

                           (iii) the fees for Seller's Broker;

                           (iv) the title insurance premium for an ALTA standard
form of owner's title policy; and

                           (v) the cost of Seller's leasehold policy of title
insurance.

                 (c) Purchaser shall pay the fees of any counsel representing
Purchaser in connection with this transaction. Purchaser shall also pay the
following costs and expenses:

                           (i) one-half of the escrow fee, if any, which may be
charged by the Escrow Agent or Title Company;



                                      -8-
<PAGE>


                           (ii) any sales tax which becomes payable by reason of
the transfer of the Personal Property;

                           (iii) any loan fees or other fees associated with the
Loan;

                           (iv) the cost of any title policy required by the
lender under the Loan ("LENDER") and the cost of any endorsements to either the
owner's title policy or lender's title policy; and

                           (v) the cost of the Survey.

                 (d) All costs and expenses incident to this transaction and the
closing thereof, and not specifically described above, shall be paid by the
party incurring same.

                 (e) The provisions of this Section 4.5 shall survive the
Closing.

         SECTION 4.6 CONDITIONS PRECEDENT TO OBLIGATION OF PURCHASER. The
obligation of Purchaser to consummate the transaction hereunder shall be subject
to the fulfillment on or before the date of Closing of all of the following
conditions, any or all of which may be waived by Purchaser in its sole
discretion:

                 (a) Seller shall have delivered all of the items required to be
delivered pursuant to the terms of this Agreement, including but not limited to,
those provided for in Section 4.2 hereof;

                 (b) all of the representations and warranties of Seller
contained in this Agreement shall be true and correct in all material respects
as of the date of Closing;

                 (c) Seller shall have performed and observed, in all material
respects, all covenants and agreements of this Agreement to be performed and
observed by Seller as of the date of Closing;

                 (d) Seller have entered into a Lease with Purchaser for the
Property in the form attached hereto as EXHIBIT I;

                 (e) the Title Company shall be prepared and irrevocably
committed to issue to Purchaser the Title Policy;

                 (f) the physical condition of the Property shall be
substantially the same on the Closing Date as on the Effective Date, reasonable
wear and tear excepted;

                 (g) no proceeding shall have been commenced against Seller
under the federal Bankruptcy Code or any state law for relief of debtors;

                 (h) the financial condition of the Seller on the Closing Date
shall not have changed in a material adverse manner from the Effective Date, as
determined by Purchaser in its reasonable discretion;



                                      -9-
<PAGE>


                 (i) no moratorium, statute or regulation of any governmental
agency or order or ruling of any court shall have been enacted, adopted, or
issued which would have a material adverse affect on Purchaser's use or
development of the Property;

                 (j) Purchaser shall have obtained a loan to be secured by a
first deed of trust on the Property in the approximate amount of $11,250,000.00
(the "LOAN") on rates and terms acceptable to Purchaser, in its sole discretion;
and

                 (k) Purchaser, in its sole discretion, shall have approved the
Survey.

         SECTION 4.7 CONDITIONS PRECEDENT TO OBLIGATION OF SELLER. The
obligation of Seller to consummate the transaction hereunder shall be subject to
the fulfillment on or before the date of Closing of all of the following
conditions, any or all of which may be waived by Seller in its sole discretion:

                 (a) Purchaser shall have delivered all of the items required to
be delivered pursuant to the terms of this Agreement, including but not limited
to, those provided for in Section 4.3 hereof;

                 (b) All of the representations and warranties of Purchaser
contained in this Agreement shall be true and correct in all material respects
as of the date of Closing;

                 (c) Purchaser shall have performed and observed, in all
material respects, all covenants and agreements of this Agreement to be
performed and observed by Purchaser as of the date of Closing;

                 (d) Purchaser shall have entered into a Lease with Seller for
the Property in form of EXHIBIT I attached hereto;

                 (e) Title Company shall be irrevocably committed to issue a
leasehold policy of title insurance acceptable to Seller;

                 (f) Seller shall have approved, in its reasonable discretion,
the terms of commitment letter of Lender for the Loan within two (2) business
days of its receipt from Purchaser;

                 (g) The provisions of the documents evidencing the Loan shall
be consistent with Lender's commitment letter; and

                 (h) Seller shall have been able to pay off in full all existing
loans encumbering the Property; provided, however, that in the event Closing
does not occur due to non-satisfaction or non-waiver of this condition, Seller
shall reimburse Purchaser, for all costs and expenses incurred by Purchaser in
contemplation of the transactions and documents set forth herein, including,
without limitation, costs associated with the Loan, preparation of this
Agreement and the Lease, and reasonable attorneys' fees; provided that Seller's
maximum reimbursement obligation hereunder shall be $250,000.00.



                                      -10-
<PAGE>


         SECTION 4.8 CLOSE OF ESCROW. Provided that Escrow Agent has received
the documents, instruments and funds described herein, provided that Escrow
Agent has not received written notice from either Purchaser or Seller that this
Agreement has been terminated or that any of the conditions to Closing set forth
herein have not been satisfied or waived and provided further that the Title
Company is able to deliver to Purchaser a commitment to issue the Title Policy
and to Seller a commitment to issue Seller's leasehold policy, then Escrow Agent
is authorized and instructed at 8:00 a.m. on the date of the Closing to:

                 (a) Record the Deed with the San Diego County Recorder; and

                 (b) Deliver the Purchase Price to Seller, as increased or
decreased by prorations and adjustments as provided herein and less Seller's
share of closing costs.

                                   ARTICLE V

                    REPRESENTATIONS, WARRANTIES AND COVENANTS

         SECTION 5.1 REPRESENTATIONS AND WARRANTIES OF SELLER. Seller hereby
makes the following representations and warranties to Purchaser as of the
Effective Date, each of which representations and warranties shall be deemed to
have been made again as of the Closing:

                 (a) ORGANIZATION AND AUTHORITY. Seller has been duly organized
and is validly existing under the laws of the State of Delaware. Seller has the
full right and authority to enter into this Agreement and to transfer all of the
Property and to consummate or cause to be consummated the transaction
contemplated by this Agreement. The execution, delivery and performance of this
Agreement have been duly authorized by all necessary action on Seller's part.
The person(s) signing this Agreement on behalf of Seller is(are) authorized to
do so;

                 (b) PENDING ACTIONS. To Seller's actual knowledge, there are no
actions, suits, arbitrations, unsatisfied orders or judgments, government
investigations or proceedings pending against Seller or the Property which, if
adversely determined, could individually or in the aggregate affect the Property
or use thereof, or Seller's ability to perform hereunder;

                 (c) OPERATING AGREEMENTS. To Seller's actual knowledge, the
Operating Agreements are all of the agreements concerning the post Closing
operation and maintenance of the Property which will impose financial
obligations upon Purchaser;

                 (d) CONDEMNATION. No condemnation proceedings are pending or,
to Seller's actual knowledge, threatened against the Property;

                 (e) VIOLATIONS. To Seller's actual knowledge, there are no
uncured violations of any federal, state or local law relating to the use or
operation of the Property which would adversely affect the Property or use
thereof;

                 (f) LEASES. There are no leases affecting the Property other
than as contemplated hereby;



                                      -11-
<PAGE>


                 (g) ENVIRONMENTAL. To Seller's actual knowledge there has not
been any release of hazardous substances on or beneath the Real Property in
violation of any federal, state or local law, and Seller has received no written
notice of any violation of claimed violation of any law, rule, or regulation
relating to hazardous substances (as used in this clause (g), "hazardous
substances" shall have the meaning set forth in Section 25359.7 of the
California Health and Safety Code);

                 (h) LIEN OR ENCUMBRANCES. To Seller's actual knowledge, title
to the Property is not subject to any liens or encumbrances (including
mechanics' liens) including, without limitation, liens or claims for delinquent
taxes, and security agreements and pledges, except for those exceptions to title
shown in the PTR or the other Permitted Exceptions;

                 (i) NO AGREEMENTS. Except for agreements terminable at will
without penalty or premium or as specified in this Agreement (including, without
limitation, the Permitted Exceptions), Seller has not entered into any
agreements or understandings concerning the Property by which Purchaser would be
bound following the Closing;

                 (j) TAXES. To Seller's actual knowledge, there are no taxes,
assessments (special, general or otherwise) or bonds of any nature assessed
against the Property, or any portion thereof, except as disclosed in the PTR;

                 (k) UTILITIES. To Seller's actual knowledge, all utilities for
servicing the Property are being provided and paid current.

         SECTION 5.2 KNOWLEDGE DEFINED. References to the "knowledge or
awareness" of Seller shall be deemed to include the present and actual knowledge
of all corporate officers of Seller (after due internal inquiry of Seller by
said officers) whose primary work involves or is associated with ownership,
operation or maintenance of the Property, and Seller's "written notice" shall be
deemed to include notices sent to the attention of one or more of said persons.

         SECTION 5.3 SURVIVAL OF SELLER'S REPRESENTATIONS AND WARRANTIES. The
representations and warranties of Seller set forth in Section 5.1 hereof as
updated as of the Closing in accordance with the terms of this Agreement, shall
survive Closing for a period of twelve (12) months following the Closing.

         SECTION 5.4 COVENANTS OF SELLER.

                 (a) MAINTENANCE OF PROPERTY. Seller hereby covenants with
Purchaser that from the Effective Date hereof until the Closing or earlier
termination of this Agreement, Seller shall maintain the Property in good
repair, reasonable wear and tear excepted, and in a manner generally consistent
with the manner in which Seller has maintained the Property prior to the date
hereof;

                 (b) NOTIFICATION OF SUBSEQUENT EVENTS. If, prior to Closing,
the Seller becomes aware of any event which would have a material adverse effect
on the condition or operation of the Property as a whole, the Seller will
immediately notify the Purchaser of such event.



                                      -12-
<PAGE>


         SECTION 5.5 REPRESENTATIONS AND WARRANTIES OF PURCHASER. Purchaser
hereby makes the following representations and warranties to Seller as of the
Effective Date, which representations and warranties shall be deemed to have
been made again as of the Closing:

                 (a) ORGANIZATION AND AUTHORITY. Purchaser has been duly
organized and is validly existing under the laws of the State of California.
Purchaser has the full right and authority to enter into this Agreement and to
consummate or cause to be consummated the transaction contemplated by this
Agreement. The execution, delivery, and performance of this Agreement have been
duly authorized by all necessary action on Purchaser's part. The person(s)
signing this Agreement on behalf of Purchaser is(are) authorized to do so; and

                 (b) PENDING ACTIONS. To Purchaser's knowledge, there is no
action, suit, arbitration, unsatisfied order or judgment, government
investigation or proceeding pending against Purchaser which, if adversely
determined, could individually or in the aggregate materially interfere with the
consummation of the transaction contemplated by this Agreement.

                                   ARTICLE VI

                                     DEFAULT

         SECTION 6.1 DEFAULT BY PURCHASER. In the event the sale of the Property
as contemplated hereunder is not consummated solely due to Purchaser's default
hereunder, Seller, as its sole remedy, shall be entitled pursuant to Section 1.6
hereof to terminate this Agreement and receive the Deposit as liquidated damages
for the breach of this Agreement.

         SECTION 6.2 DEFAULT BY SELLER. In the event the sale of the Property as
contemplated hereunder is not consummated due to Seller's default hereunder,
Purchaser shall be entitled, in addition to all other remedies available at law
or in equity, to: (a) receive the return of the Deposit, which return shall
operate to terminate this Agreement; (b) enforce specific performance of
Seller's obligation to convey the Property to Purchaser in accordance with the
terms of this Agreement, it being understood and agreed that the remedy of
specific performance shall not be available to enforce any other obligation of
Seller under this Agreement; or (c) collect damages in the amount of all of
Purchaser's costs incurred in connection with the proposed transaction
contemplated by this Agreement.

                                  ARTICLE VII

                                  RISK OF LOSS

         SECTION 7.1 RISK OF LOSS. Any risk of loss to the Property shall be
borne by Seller until the Closing. If prior to the Closing there are instituted
any proceedings, whether judicial, administrative, or otherwise, which relate to
the taking of any material portion of the Property by eminent domain or the
Property is destroyed or materially damaged in whole or in part, Purchaser shall
have the right to terminate this Agreement by giving Seller written notice
within five (5) business days after it has received notice of such eminent
domain proceeding or destruction of the Property. Upon any termination pursuant
to this Section 7.1, the parties shall proceed as if this Agreement had been
terminated pursuant to Section 3.3 hereof. If Purchaser



                                      -13-
<PAGE>


does not terminate this Agreement, then at the Closing, Seller shall assign to
Purchaser all of its right, title, and interest in any proceeds or award arising
out of such taking or destruction.

                                  ARTICLE VIII

                                   COMMISSIONS

         SECTION 8.1 BROKERAGE COMMISSIONS. With respect to the transaction
contemplated by this Agreement, Seller represents that its sole broker is CB
Richard Ellis ("SELLER'S BROKER"). Each party hereto agrees that if any person
or entity, other than the Seller's Broker, makes a claim for brokerage
commissions or finder's fees related to the sale of the Property by Seller to
Purchaser, and such claim is made by, through or on account of any acts or
alleged acts of said party or its representatives, said party will protect,
indemnify, defend and hold the other party free and harmless from and against
any and all loss, liability, cost, damage and expense (including reasonable
attorneys' fees) in connection therewith. The provisions of this paragraph shall
survive Closing or any termination of this Agreement.

                                   ARTICLE IX

                                    INDEMNITY

         SECTION 9.1 INDEMNIFICATION BY SELLER. From and after the Closing,
Seller shall indemnify and hold Purchaser, its affiliates, members and partners,
and the partners, shareholders, officers, directors, employees, representatives
and agents of each of the foregoing harmless from and against any and all
liability, costs, fees, expenses, damages, deficiencies, interest and penalties
(including, without limitation, reasonable attorneys' fees and disbursements)
(collectively, "LOSSES") arising out of, or in any way relating to (i) any
breach of any representation or warranty of Seller contained in this Agreement
or in any Schedule, certificate, instrument or other document delivered pursuant
hereto, (ii) any breach of any covenant of Seller contained in this Agreement,
and (iii) any event, act, or omission on the part of Seller relating to the
Property and arising prior to the Closing notwithstanding when the claim for the
Loss is asserted. The obligations of this Section 9.1 shall survive the Closing.

         SECTION 9.2 INDEMNIFICATION BY PURCHASER. From and after the Closing,
Purchaser shall indemnify and hold Seller, its affiliates and shareholders, and
the partners, shareholders, officers, directors, employees, representatives and
agents of each of the foregoing harmless from and against any and all Losses
arising out of, or in any way relating to (i) any breach of any representation
or warranty of Purchaser contained in this Agreement or in any Schedule,
certificate, instrument or other document delivered pursuant hereto, (ii) any
breach of any covenant of Purchaser contained in this Agreement, and (iii) any
event, act, or omission on the part of Purchaser relating to the Property and
arising after the Closing. The obligations of this Section 9.2 shall survive the
Closing.



                                      -14-
<PAGE>


                                    ARTICLE X

                                  MISCELLANEOUS

         SECTION 10.1 CONFIDENTIALITY. Except when required to disclose by
applicable law, including public company reporting requirements (it being
understood by the parties that Seller, as a public company, may need to disclose
the transaction contemplated hereby upon the execution of this Agreement), each
party and its representatives shall hold in strictest confidence all data and
information obtained with respect to the Property or the transaction
contemplated hereunder, whether obtained before or after the execution and
delivery of this Agreement and whether or not marked "confidential," and shall
not disclose the same to others; provided, however, that it is understood and
agreed that the parties may disclose such data and information to their
employees, lenders, consultants, accountants and attorneys provided that such
persons agree to treat such data and information confidentially. In the event
this Agreement is terminated or Purchaser fails to perform hereunder, Purchaser
shall promptly return to Seller any statements, documents, schedules, exhibits
or other written information obtained from Seller in connection with this
Agreement or the transaction contemplated herein. The provisions of this Section
10.1 shall survive Closing or any termination of this Agreement.

         SECTION 10.2 PUBLIC DISCLOSURE. Except when required to disclose by
applicable law, including public company reporting requirements (it being
understood by the parties that Seller, as a public company, may need to disclose
the transaction contemplated hereby upon the execution of this Agreement), prior
to the Closing, any release to the public of information with respect to the
sale contemplated herein or any matters set forth in this Agreement will be made
only in the form reasonably approved in writing by Purchaser and Seller. The
provisions of this Section 10.2 shall survive the Closing or any termination of
this Agreement.

         SECTION 10.3 ASSIGNMENT. Subject to the provisions of this Section
10.3, the terms and provisions of this Agreement are to apply to and bind the
permitted successors and assigns of the parties hereto. Purchaser may not assign
its rights under this Agreement without first obtaining Seller's written
approval, which approval may not be unreasonably withheld. In the event
Purchaser intends to assign its rights hereunder: (a) Purchaser shall send
Seller written notice of its request at least ten (10) business days prior to
Closing, which request shall include the legal name and structure of the
proposed assignee, as well as any other information that Seller may reasonably
request; and (b) Purchaser and the proposed assignee shall execute an assignment
and assumption of this Agreement in form and substance satisfactory to Seller.

         SECTION 10.4 NOTICES. Any notice pursuant to this Agreement shall be
given in writing by: (a) personal delivery; (b) reputable overnight delivery
service with proof of delivery;(c) United States Mail, postage prepaid,
registered or certified mail, return receipt requested; or (d) legible facsimile
transmission, sent to the intended addressee at the address set forth below, or
to such other address or to the attention of such other person as the addressee
shall have designated by written notice sent in accordance herewith, and shall
be deemed to have been given upon receipt or refusal to accept delivery, or, in
the case of facsimile transmission, as of the date of the facsimile transmission
provided that an original of such facsimile is also sent to the intended
addressee by means described in clauses (a), (b) or (c) above. Unless changed in



                                      -15-
<PAGE>


accordance with the preceding sentence, the addresses for notices given pursuant
to this Agreement shall be as follows:

         If to Seller:              QUIDEL CORPORATION
                                    10165 McKellar Court
                                    San Diego, California  92121
                                    Attention:  Charles J. Cashion
                                    Telephone No. 858-552-7962
                                    Telecopy No. 858-646-8016

         with a copy to:            Gibson Dunn & Crutcher
                                    Jamboree Plaza, 4 Park Plaza
                                    Irvine, California  92614-8557
                                    Attention:  Teresa J. Farrell, Esq.
                                    Telephone No. (949) 451-3800
                                    Telecopy No. (949) 451-4220

         If to Purchaser:           10165 MCKELLAR COURT, L.P.
                                    11440 W. Bernardo Court, Suite 208
                                    San Diego, California  92127
                                    Attention:  Alan D. Gold
                                    Telephone No. 858-485-9840
                                    Telecopy No. 858-485-9843

         with a copy to:            Seltzer Caplan Wilkins & McMahon
                                    750 B Street, Suite 2100
                                    San Diego, California  92101
                                    Attention:  David J. Dorne, Esq.
                                    Telephone No. 619-685-3003
                                    Telecopy No. 619-685-6806

         SECTION 10.5 MODIFICATIONS. This Agreement cannot be changed orally,
and no executory agreement shall be effective to waive, change, modify or
discharge it in whole or in part unless such executory agreement is in writing
and is signed by the parties against whom enforcement of any waiver, change,
modification or discharge is sought.

         SECTION 10.6 ENTIRE AGREEMENT. This Agreement, including the exhibits
and schedules hereto, contains the entire agreement between the parties hereto
pertaining to the subject matter hereof and fully supersedes all prior written
or oral agreements and understandings between the parties pertaining to such
subject matter.

         SECTION 10.7 FURTHER ASSURANCES. Each party agrees that it will execute
and deliver such other documents and take such other action, whether prior or
subsequent to Closing, as may be reasonably requested by the other party to
consummate the transaction contemplated by this Agreement. The provisions of
this Section 10.7 shall survive Closing.



                                      -16-
<PAGE>


         SECTION 10.8 COUNTERPARTS. This Agreement may be executed in
counterparts, all such executed counterparts shall constitute the same
agreement, and the signature of any party to any counterpart shall be deemed a
signature to, and may be appended to, any other counterpart.

         SECTION 10.9 FACSIMILE SIGNATURES. In order to expedite the transaction
contemplated herein, telecopied signatures may be used in place of original
signatures on this Agreement. Seller and Purchaser intend to be bound by the
signatures on the telecopied document, are aware that the other party will rely
on the telecopied signatures, and hereby waive any defenses to the enforcement
of the terms of this Agreement based on the form of signature.

         SECTION 10.10 SEVERABILITY. If any provision of this Agreement is
determined by a court of competent jurisdiction to be invalid or unenforceable,
the remainder of this Agreement shall nonetheless remain in full force and
effect; provided that the invalidity or unenforceability of such provision does
not materially adversely affect the benefits accruing to any party hereunder.

         SECTION 10.11 APPLICABLE LAW. This Agreement shall be governed by and
construed in accordance with the laws of the State of California. Furthermore,
substantial obligations under this Agreement are to be performed in San Diego,
California. The parties select San Diego, California as the proper and sole
venue for any action filed to enforce, construe, or interpret this Agreement.
Purchaser and Seller agree that the provisions of this Section 10.11 shall
survive the Closing or any termination of this Agreement.

         SECTION 10.12 NO THIRD-PARTY BENEFICIARY. The provisions of this
Agreement and of the documents to be executed and delivered at Closing are and
will be for the benefit of Seller and Purchaser only and are not for the benefit
of any third party, and accordingly, no third party shall have the right to
enforce the provisions of this Agreement or of the documents to be executed and
delivered at Closing.

         SECTION 10.13 CAPTIONS. The section headings appearing in this
Agreement are for convenience of reference only and are not intended, to any
extent and for any purpose, to limit or define the text of any section or any
subsection hereof.

         SECTION 10.14 CONSTRUCTION. The parties acknowledge that the parties
and their counsel have reviewed and revised this Agreement and that the normal
rule of construction to the effect that any ambiguities are to be resolved
against the drafting party shall not be employed in the interpretation of this
Agreement or any exhibits or amendments hereto.

         SECTION 10.15 ATTORNEYS' FEES. In the event of any dispute,
arbitration, action, or other proceeding brought by either party against the
other under this Agreement, the prevailing party shall be entitled to recover
all costs and expenses incurred in connection with such dispute, arbitration,
action, or other proceeding, including, without limitation, the fees and costs
of its attorneys, whether or not such dispute, arbitration, action, or other
proceeding proceeds to formal resolution or judgment.

         IN WITNESS WHEREOF, the parties hereto have duly executed this
Agreement as of the Effective Date.



                                      -17-
<PAGE>


SELLER:

QUIDEL CORPORATION,
a Delaware corporation


By:  /s/ Andre de Bruin
    ------------------------------------------
Name:    Andre de Bruin
      ----------------------------------------
Title:   President and Chief Executive Officer
      ----------------------------------------

By:  /s/ Charles J. Cashion
    ------------------------------------------
Name:    Charles J. Cashion
      ----------------------------------------
Title:   Senior Vice President
      ----------------------------------------

                     [SIGNATURES CONTINUED ON THE NEXT PAGE]




                                      -18-
<PAGE>



PURCHASER:

10165 MCKELLAR COURT, L.P.,
a California limited partnership

By:  SCIMED PROP II, LLC,
       a California limited liability company,
       its General Partner

By:  /s/ Alan D. Gold
     --------------------------
         Alan D. Gold, Member

         The undersigned acknowledges receipt of this Agreement and agrees to
act as Escrow Agent pursuant to the terms hereof.

                                            ESCROW AGENT:
                                            FIDELITY NATIONAL TITLE COMPANY


                                            By:  /s/  Thomas W. Ahern
                                                ------------------------------
                                            Name:  Thomas W. Ahern
                                                 -----------------------------
                                            Title:  Escrow Officer
                                                  ----------------------------


                                      -19-
<PAGE>


                                    EXHIBIT I

                                      LEASE

                        [SEE EXHIBIT 10.7 TO THIS FILING]