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4.26   ASSET PURCHASE AGREEMENT BY AND BETWEEN AMEX PLASMA MANAGEMENT, INC. AND
       SERACARE, INC. DATED OCTOBER 30, 1998.












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                              ASSET PURCHASE AGREEMENT

                           BY AND BETWEEN SERACARE., INC.

                                        AND

                           AMEX PLASMA MANAGEMENT, INC.





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       This Asset Purchase Agreement ("Agreement") is made and entered into
this 30th day of October, 1998 by and between SeraCare, Inc., a Delaware
Corporation with its principal place of business at 1925 Century Park East,
Suite 1970, Los Angeles, CA. 90067 ("Purchaser") and Amex Plasma Management,
Inc. with its principal place of business at 177 U.S. Highway One, Suite 285,
Tequesta, Florida, 33469 ("Seller").

                                       RECITALS

       WHEREAS, Purchaser wishes to acquire from Seller and the Seller wishes
to sell to Purchaser, upon the terms and subject to the conditions set forth
herein, the Purchased Assets (defined below) which shall include all of the
operating assets of the plasmapheresis donor center located at 4226 Plank Road,
Baton Rouge, LA 70805 (the "Plasma Center").

                                      AGREEMENTS

       Seller agrees to sell to Purchaser all rights and interests in the
Purchased Assets, leases, leasehold improvements, fixed assets, intangible
assets, licenses, certifications and/or any other personal or intangible
property attributable to the Plasma Center.

PURCHASE AND SALE OF ASSETS. Subject to the terms and conditions of this
Agreement, on the Closing Date, as defined herein, Seller shall sell, assign,
transfer, convey and deliver to Purchaser (or its designee), and Buyer (or its
designee) shall purchase, acquire and accept from Seller, all of the assets,
properties, rights, privileges, claims and rights of every kind and nature,
tangible and intangible, absolute or contingent, used by Seller in connection
with the Plasma Center, excluding cash, accounts receivable and plasma inventory
(the "Purchased Assets"), which Purchased Assets shall include an assignment of
the leases, leasehold improvements, fixed assets, all rights and obligations
attributable to sales contracts to customers, intangible assets (including
goodwill), plus ownership in any and all other rights or assets attributable to
the Plasma Center, including the rights to any FDA or QPP licenses and/or
certifications pertaining to such plasma center, and including any other asset
or license which attach or may attach to the Plasma Center and the operation
thereof.

ASSUMPTION OF CERTAIN LIABILITIES. Upon the terms and subject to the conditions
contained herein, on the Closing Date Purchaser shall assume the following
liabilities:

       1.      The lease for the facilities located at 4226 Plank Road, Baton
               Rouge, LA 70805, a copy of which is attached hereto as Exhibit 1.

       2.      The obligations under the Plasma Purchase Agreement with Alpha
               Therapeutics Company, a copy of which is attached as exhibit 2

       3.      All other contracts, agreements policies, licenses, permits and
               certifications in effect on the Closing Date and which are listed
               on Schedule 2 attached hereto under the heading "Other Contracts
               and Obligations".

       4.      Other than those liabilities and obligations listed on Schedule
               2, Purchaser assumes no responsibility for any other liability,
               obligation or account payable


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               relating to the period up to and including October 31, 1998.
               Accounts payable, such as utility bills, which cover periods
               before and after October 31, 1998 will be prorated, with
               Purchaser paying only for the period beginning November 1, 1998.


                                    CONSIDERATION

PURCHASE CONSIDERATION. As consideration to Seller, Purchaser agrees to
deliver 50,000 shares of .001 par value common stock of the Purchaser issued
with a Rule 144 legend and a five year warrant to purchase 50,000 shares of
 .001 par value common stock at a price of $6.00 per common share. Such share
certificate and warrant shall be issued within fifteen days of the Closing
Date. As additional consideration, the Purchaser hereby agrees to negotiate
in good faith a definitive development agreement for the construction of
additional plasmapheresis centers by Seller to be acquired by Purchaser on a
"Turn Key" basis.

PIGGY- BACK RIGHTS.
As part of the consideration, Purchaser agrees that Seller shall have Piggy-Back
Registration Rights with regard to both the common stock shares issued hereunder
and any common stock shares issued pursuant to the exercise of the warrant
issued hereunder. Purchaser hereby agrees to provide Seller with prompt written
notice of any proposed registration together with a list of the jurisdictions in
which the SeraCare, Inc. intends to attempt to qualify such securities under
applicable state securities laws. Upon written request from the Seller given 30
days after receipt of such notice from the Purchaser, the Purchaser shall cause
to be included in the noticed registration statement all of the common shares
that the Seller has requested, subject only to restrictions and conditions
imposed by the underwriters.

                           CONDITIONS PRECEDENT TO CLOSING

BY SELLER. Seller shall fulfill all of the following before Purchaser is
obligated to close:

       a.      have provided Purchaser with copies of all documents listed on
               Schedule 2.

       b.      have provided Purchaser with a Lease Assignment signed by the
               appropriate landlord for all leases listed on Schedule 2 in a
               form reasonably satisfactory to Purchaser.

       c.      have provided purchaser with a waiver of Alpha Therapeutic
               Corporation's First Right of Refusal re: the Plasma Center and a
               written consent and assignment to SeraCare, Inc. (or its
               designate) of the obligations, rights and privileges of the
               Plasma Purchase and Sale Agreement from Alpha Therapeutic
               Corporation.

       d.      have provided documented evidence that all FDA licenses and QPP
               certifications are valid and in good standing with the
               appropriate authority and that there no outstanding issues with
               any such authority.

       e.      have delivered all other consents, approvals and assignments
               required in connection with the completion of the transaction
               contemplated by this


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               Agreement in form and content reasonably satisfactory to the
               Purchaser.

BY PURCHASER. Purchaser shall fulfill all of the following before Seller is
obligated to close:

       a.      have provided Seller with a copy of a Board of Directors
               resolution authorizing the transaction contemplated by this
               agreement.

       b.      have provided Seller with a Draft letter instructing the
               Purchaser's transfer agent to issue 50,000 shares of .001 par
               value Common Stock of SeraCare, Inc. to the Seller.

       c.      have provided Seller with a Draft copy of a five-year warrant to
               purchase 50,000 shares of .001 par value common stock.

       d.      have delivered all consents, approvals and assignments required
               in connection with the completion of the transaction contemplated
               by this Agreement in form and content reasonably satisfactory to
               the Seller.

                            REPRESENTATIONS AND WARRANTIES

Seller hereby represents and warrants to the Purchaser as follows (with the
understanding that the Purchaser is relying materially on each such
representation and warranty in entering into and executing this Agreement):

A.     OWNERSHIP IN THE LEASES. RIGHTS AND INTERESTS BEING ACQUIRED BY THE
       PURCHASER FREE AND CLEAR OF ALL ENCUMBRANCES. Seller hereby represents
       and warrants that he has good title, valid rights and ownership free and
       clear of all encumbrances to the Transferred Assets with every authority
       to transfer, assign and sell such interest, right or ownership to the
       Purchaser as contemplated by this Agreement.

B.     All FDA LICENSES, QPP CERTIFICATIONS AND ANY OTHER LICENSE OR PERMITS
       NEEDED TO OPERATE THE PLASMA CENTER ARE IN GOOD STANDING WITH NO
       OUTSTANDING AND/OR UNRESOLVED ISSUES. Seller hereby represents and
       warrants that All FDA licenses, QPP certifications and any other license
       or permits needed to operate the Plasma Center are in good standing with
       no outstanding and/or unresolved issues. Seller further represents and
       warrants that there are no unresolved audit issues with Alpha
       Therapeutic Corporation.

C.     DUE AUTHORIZATION. The Seller has full power and authority as a Company
       to enter into and perform the obligations under this Agreement and each
       agreement, instrument and document to be executed by the Seller in
       accordance herewith.

D.     ALL LIABILITIES AND OBLIGATIONS HAVE BEEN LISTED ON SCHEDULE 2. Seller
       hereby represents and warrants that all leases, contracts or other
       obligations to be assumed by the Purchaser have been listed on Schedule
       2 and that Seller knows of no other leases, contracts or other
       obligations relating to the Plasma Center. Seller understands that any
       leases, finder's fees, commissions, contracts or other obligations not
       listed on Schedule 2 will not be assumed by Purchaser.


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E.     COMPLIANCE WITH LAWS: ENVIRONMENT MATTERS. Seller hereby represents and
       warrants that conduct of Seller has not violated any laws, the
       non-compliance with which could have a materiel adverse effect on the
       Purchaser or the operation of the Plasma Center as a plasma collection
       center. The Seller has compiled in all material respects with all
       judicial and governmental requirements relating to any federal, state or
       local environmental laws, regulations or ordinances, the non-compliance
       with which would have a material adverse effect on the Purchaser or the
       operation of the Plasma Center.

F.     LEGAL PROCEEDINGS. Seller hereby represents and warrants that there is
       no Order or Action pending, or to the best knowledge of the Seller,
       threatened which affects or may affect Seller or the Transferred Assets
       that individually or when aggregated with one or more other Orders or
       Actions has or could reasonably be expected to have a material adverse
       effect on the Plasma Center or on the Sellers ability to perform Sellers
       obligations under the terms of this Agreement.

G.     NO BROKERS OR FINDERS. Seller hereby represents and warrants that no
       agent, broker, finder, or investment or commercial banker, or other
       Person or firm engaged by or acting on behalf of Seller or any of
       Sellers relatives or affiliates in connection with the negotiation,
       execution or performance of the transaction contemplated by this
       Agreement, is or will be entitled to any brokerage or finder's or
       similar fee or other commission as a result of this Agreement or the
       transaction contemplated hereby.

H.     INDEMNIFICATION OF PURCHASER. Seller hereby agrees to indemnify and hold
       harmless the Purchaser, affiliates of the Purchaser, and any officer,
       director, employee and consultant of the Purchaser (collectively, the
       "Indemnified Parties") from and against any and all damages, losses,
       claims, liabilities, demands, charges, suits, penalties, costs and
       expenses which any of the Indemnified Parties may sustain, or to which
       any of the Indemnified Parties may be subjected, arising out of any
       breach or default by the Seller, excluding actions or omissions of the
       Purchaser, of or under any of the representations, warranties,
       covenants, agreements or other provisions of this Agreement or any
       agreement or document executed in connection herewith.

I.     SURVIVAL OF REPRESENTATIONS AND WARRANTIES. Regardless of any
       investigation at any time made by or on behalf of any party hereto or of
       any information any party may have in respect thereof, all covenants,
       agreements, indemnities, representations and warranties made hereunder
       or pursuant hereto or in connection with the transactions contemplated
       hereby shall survive the execution of this Agreement for a period of
       thirty six months following the date hereof.

J.     NO MATERIAL ADVERSE CHANGE. Between the date of the signing of this
       Agreement and November 1, 1998, Seller has no knowledge of any
       circumstance, change in business conditions, or other event which may
       occur or continue to occur which could reasonably expected to have a
       material adverse effect on the Plasma Center. During that period, Seller
       will continue to direct the activities of the Plasma Center in a prudent
       business manner.

K.     NON COMPETITION AGREEMENT. Seller hereby agrees that for a period of
       five years from the Closing Date, Seller will not (i) directly or
       indirectly, either alone or with others, as principal, agent, partner,
       investor, lender, guarantor, distributor, promoter


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       or advertiser, or advisor, or in any other capacity, carry on, be
       engaged in, or have any interest or otherwise be connected or affiliated
       or associated with any corporation, partnership, limited liability
       company or partnership, proprietorship, firm, association or other
       entity which is engaged in any manner in, or otherwise competes with,
       the Purchaser (ii) engage in any activities which are or could
       reasonably be expected to have an adverse affect upon the operations of
       the Purchaser (iii) open or acquire any new center that will be in the
       business of collecting, analyzing, processing and selling human blood
       plasma and/or human biological products or components (iii) directly or
       indirectly, solicit, or request that any person who is currently
       donating, or in the one year prior to the Closing Date has donated,
       plasma at The Plasma Center or at any other center owned or controlled
       by the Purchaser or any affiliated (as that term is defined by the
       Securities Exchange Commission) entity of the Purchaser. Both Seller and
       Purchaser hereby agree that the covenants of non-competition and
       non-solicitation are reasonable covenants under the circumstances.
       Seller agrees that any breach or threatened breach of the covenants
       contained in this paragraph K would irreparably injure the Purchaser.
       Accordingly, Seller hereby agrees that, in such event, the Buyers shall
       be entitled, without the necessity of proving damages or posting bond,
       and notwithstanding any election by Purchaser to claim damages, to
       obtain a temporary and/or permanent injunction (without proving a breach
       therefor) to restrain any such breach or threatened breach or to obtain
       specific performance of any such provisions, all without prejudice to
       any and all remedies which the Purchaser may have at law or in equity.

CLOSING DATE. The closing date of the transaction contemplated by this Agreement
shall take place on October 31, 1998, at the offices of the Purchaser (the
"Closing" or "Closing Date") or at some other time, date and place agreed upon
by both the Seller and the Purchaser.

CONFIDENTIALITY. The parties agree the material terms of this Agreement shall
remain absolutely confidential. In the event any party or any officer, director,
shareholder or representative of either party to this agreement is required to
disclose the existence or terms of this Agreement by subpoena, discovery or
legal process, then such party shall utilize its best efforts to notify the
opposing parties prior to any disclosure so as to provide the opposing parties
with an opportunity to intervene for the purpose of protecting its interests in
non-disclosure.

JOINT DRAFTING. Both Seller and Purchaser have jointly participated in the
negotiations and drafting of this Agreement. In the event of a question of
intent or interpretation arises, this Agreement shall be construed as having
been drafted by both parties.

ATTORNEY'S FEES. In the event of any dispute arising out of or related to this
Agreement, the prevailing party shall be entitled to recover, in addition to any
other damages afforded by law, all reasonable attorney's fees incurred in the
prosecution and defense of such and action.

APPLICABLE LAW. This Agreement shall be governed by and construed in accordance
with the laws of the State of California.

ENTIRE AGREEMENT. This Agreement supersedes any and all other agreements,
either oral or in writing, between the parties hereto with respect to the
transaction contemplated by this Agreement. Each party to this Agreement
acknowledges that no


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representation, inducements, promises, or agreements, orally or otherwise, have
been made by any party, or anyone acting on behalf of any party, which are not
embodied herein, and that no other agreement, statement, or promise not
contained in this Agreement shall be valid or binding on either party.

MODIFICATIONS. Any modification of this Agreement shall be effective only if it
is in writing and signed by both parties to this Agreement.

       IN WITNESS WHEREOF, the parties have executed this Agreement on the
date and year first written above.

SELLER:

AMEX PLASMA MANAGEMENT,, INC.


By:  /s/ June L. Ferren
    --------------------------
Name:  June L. Ferren
Title: President



PURCHASER:

SERACARE, INC.

By:  /s/ Barry Plost
    --------------------------
Barry D. Plost
President and CEO


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