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                                                                    EXHIBIT 10.4

                                                                REDACTED VERSION

                           ALBUMIN SUPPLY AGREEMENT

     *** Confidential treatment has been requested as to certain portions of
     this agreement. Such omitted confidential information has been designated
     by an asterisk and has been filed separately with the Securities and
     Exchange Commission pursuant to Rule 24b-2 under the Securities Exchange
     Act of 1934, as amended, and the Commission's rules and regulations
     promulgated under the Freedom of Information Act, pursuant to a request for
     confidential treatment. ***


In Barcelona on this 22 day of June 1999.

                                BY AND BETWEEN

SERACARE INC., a corporation of USA nationality, with address at 1926 Century
Park East, Suite 1970, Los Angeles, California, USA, represented by Mr. Barry D.
Plost, by virtue of his position as Chairman/CEO (hereinafter referred to as
SERACARE), party to the first part.

INSTITUTO GRIFOLS, S.A., a corporation of Spanish nationality, with address at
Poligono Industrial Levante, Calle Can Guasch, s/n. 08150 Parets del Valles,
Barcelona, Spain, represented by Mr. Javier Jorba Ribes, by virtue of his
position as General Manager, (Hereinafter referred to as GRIFOLS), party of the
second part.

                                    WHEREAS

I.   SERACARE is a corporation, which main activity is as a collector of plasma,
     distributor of therapeutic and diagnostic plasma derived products, and as a
     manufacturer of diagnostic products.

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II.   GRIFOLS is a corporation, which main activity is the manufacturing and
      commercialization of Hemoderivatives, including Human Albumin, which are
      manufactured in it premises located in Parets del Valles.

III.  GRIFOLS declares that its Human Albumin complies with the technical
      specifications that are detailed in Annex 1 attached hereto, and has all
      the necessary and required permits.

IV.   That both parties know that GRIFOLS Human Albumin is manufactured for
      its direct use and only in accordance with the product indications
      described in Annex 2 attached hereto.

V.    GRIFOLS is willing to supply and SERACARE to acquire, Human Albumin
      (hereinafter referred to as Albumin), due to which, both parties
      recognizing in each other enough legal capacity, agree to enter into the
      present Albumin Supply Agreement in accordance with the following.

                                    CLAUSES

FIRST -  Constitutes the object of the present Agreement, the supply to SERACARE
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of Human Albumin manufactured by GRIFOLS, to be sold by SERACARE to third
parties, which may only use said Human Albumin as raw material in its production
of certain products, and never for direct use, in accordance with the provisions
of this Agreement.

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SECOND -  Due to the special technical specifications and quality controls that
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the Albumin has to comply with, the parties agree that all the Albumin supplied
by GRIFOLS to SERACARE will have a certified batch release from GRIFOLS.

THIRD -  The Albumin supplied by GRIFOLS to SERACARE will be used by any third
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party only as raw material, for the purpose of manufacturing products listed in
Annex 3.  No other use different from this, including its human use, is covered
by the present Agreement.

The Albumin supplied by GRIFOLS to SERACARE will not be mixed in the
manufacturing process of the products listed in Annex 3 carried out by any third
party with any other product of human origin.

GRIFOLS shall have the right, with prior notification of 24 hours, to require
SERACARE to inspect any third parties' manufacturing facilities and records in
order to verify the correct use of the Albumin supplied/sold by SERACARE to this
third party in accordance with the provisions of the present Agreement.

FOURTH -  The quality and technical specifications of the Albumin supplied by
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GRIFOLS to SERACARE, as detailed in Annex 1.

The quality and technical specifications, may be changed and/or modified, at
GRIFOLS' requirement, in order to comply with any new legislation in force
and/or new controls or test methods.  Any change carried out in accordance will
be duly notified to SERACARE, which shall notify it to all third parties to whom
the Albumin has been supplied/sold.

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Every shipment of Albumin will be shipped together with all the mandatory and/or
legal documents, as well as any other documents that may be required.

FIFTH -  SERACARE will acquire from GRIFOLS the annual quantities established in
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Annex 4.  Both parties, on a yearly basis, will fix these minimum annual
quantities, as well as the Product price, which will also be included in said
Annex.

In the event that / new test and/or control is required, as stated in Clause
Fifth hereinabove, GRIFOLS and SERACARE shall mutually agree to renegotiate the
prices set forth in this Agreement.

SIXTH -  Payment of the Albumin delivered by GRIFOLS to SERACARE would be
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payable 30 days after reception by SERACARE in its premises in Oceanside, CA,
USA.

SEVENTH -  The Albumin will be shipped and packed in accordance with the
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specifications set forth in Annex 5 to the present Agreement.

EIGHTH -  For the event that the Albumin supplied by GRIFOLS to SERACARE is
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object of a product recall carried out by GRIFOLS, GRIFOLS will be responsible
only for its reposition with new Albumin.

Due to the use that third parties shall give to the Albumin, which will be as
raw material for manufacturing products listed in Annex 3 which is different and
not specified in the Product indications given by GRIFOLS, SERACARE and/or any
third party will be solely responsible for its use in accordance with the
present Agreement, and will hold GRIFOLS harmless of any

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circumstances derived from the use that SERACARE and/or any third party will
give to the Albumin.

NINTH -  SERACARE declares that it has a product liability insurance covering
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the products, for an amount of $US 5,000,000 and takes the commitment to have
such insurance coverage while the present Agreement is in force and the products
manufactured using the Albumin have not expired, and will also require that any
third party using the Albumin has a product liability insurance in the same
terms and conditions.

TENTH -  All information disclosed by GRIFOLS to SERACARE concerning any aspect
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of Albumin, including discussions with Regulatory Authorities, shall be
considered as Confidential Information under this Agreement.

The party receiving the Confidential Information:

1.   Will not disclose the Confidential Information to any third party, except
     as required by the Regulatory Authorities strictly for the purposes of this
     Agreement.

2.   Will limit disclosure of the Confidential Information to its employees and
     agents who, under obligation of confidentiality, have a need to know of it
     for the purposes of this Agreement.

3.   Will make no use of the received Confidential Information other than to
     fulfill the purposes of this Agreement.

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4.   On termination of this Agreement, will return all such Confidential
     Information to the disclosing party, without retaining any copy or extract
     thereof.

The following will be exempt from the obligation of this Article:

a)   Confidential Information which is now, or which becomes, part of the public
     domain without involvement of the receiving party.

b)   Confidential Information which the receiving party can demonstrate by
     competent proof was known to it before being received from the disclosing
     party.

c)   Confidential Information which becomes available to the receiving party
     from a third party under no obligation of confidentiality to the disclosing
     party.

The obligations of this article shall continue after termination of this
Agreement.

ELEVENTH -  SERACARE shall, prior to any sale of Albumin to any third party,
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inform GRIFOLS of the identity of said third party, as well as sign an agreement
with this third party that shall cover the following:

-    Use that this third party may do of the Albumin, which is as detailed in
     the manufacturing of products listed in Annex 3.

-    Manufacturing information by which this third party has to inform SERACARE
     and GRIFOLS of the lot numbers of the products manufactured using GRIFOLS
     Albumin.

-    Product liability insurance as foreseen in Clause Ninth of the present
     Agreement.

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-    Signature of a Confidential Disclosure Agreement between said third party
     and GRIFOLS, which will be that attached as enclosure 6 hereto.

-    Responsibility Clause identical to that foreseen in Clause Eighth of the
     present Agreement.

-    Force Majeure Clause identical to that foreseen in Clause Thirteenth of the
     present Agreement.

-    Rescission/termination clause, which covers any breach of the clauses of
     the Agreement by the third party, especially if the Albumin is not used as
     raw material in the manufacturing of products listed in Annex 3, and a
     different use is given to it.

-    Clause including that SERACARE shall have the right, with a prior
     notification of 24 hours, to inspect the third parties' manufacturing
     facilities and records, in order to verify the correct use of the Albumin
     supplied by GRIFOLS in accordance with the provisions of the present
     Agreement.

TWELFTH -  The duration of the present Agreement will be until 31/st/ December
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1999, and will start on the date of its signature.  The Agreement will be
automatically renewed for one-year periods if neither party denounces it three
months before its expiry.

THIRTEENTH -  Neither party shall be liable for non-performance of this
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Agreement due to Force Majeure.  Force Majeure will have the meaning stated
below under (a):

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a)   Strikes, lockouts, other industrial disturbances, rebellions, mutinies,
     epidemics, landslides, lightning, earthquakes, fires, storms, floods,
     sinking, drought, civil disturbances, explosions, act or decisions of duly
     constituted municipal, state or National Governmental Authorities or of
     Courts of Law, impossibility to obtain supplies, fuel or other required
     materials, or any other causes similar or completely different, all beyond
     the control of the Party pleading Force Majeure preventing the Party from
     performing its rights and obligations and not to be overcome by due
     diligence of such Party.

b)   The Parties agree that if either of them find themselves wholly or partly
     unable to fulfill their respective obligations in this Agreement by reason
     of Force Majeure, the Party pleading Force Majeure will as soon as possible
     notify the other Party of its inability to perform giving detailed
     explanation of the occurrence which excuses performance.  If said notice is
     given, the performance of the notifying party shall be abated for so long
     as performance may be prevented by Force Majeure.  A Party unable to
     perform due to Force Majeure shall resume fulfilling its obligations,
     including making the due payments, after the Force Majeure has ceased.  All
     terms will be extended by the time period the Force Majeure has lasted.

FOURTEENTH -  The present Agreement will be terminated and will become null due
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to any of the following reasons:

a)   Mutual agreement.

b)   Those fixed by law.

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c)   With thirty (30) days notice if the other party shall default in the
     performance or observation of any material provisions of this Agreement and
     shall fail to cure such default within sixty (60) days after notice from
     such party, and the non-defaulting party shall reserve a right to seek a
     remedy available under the applicable laws.

d)   If any party falls into suspension of payments or becomes bankrupt.

e)   Not meeting payments due.

f)   Any substantial change in the ownership in any of the parties which may
     give rise to a change in the political control of the Company, or the
     participation through the acquisition of shares by a direct competitor of
     any of the parties.

FIFTEENTH -
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a)   Any notice required or provided for by the terms of this Agreement shall be
     made in writing and shall be sent by registered mail postage prepaid or by
     telex or by facsimile properly addressed in accordance with the addresses
     first above given or to such other addresses as the parties may at a later
     date advise.  The effective date of this notice shall be six (6) days after
     the date of sending such notice.

b)   This Agreement constitute the entire agreement between the parties
     concerning the subject matter hereof.  None of the terms of this Agreement
     shall be amended or modified except in writing signed by the parties
     hereto.  The headings used in this Agreement are only meant for easy
     reading of the Agreement.

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c)   Provisions of this Agreement are separate and divisible and the invalidity
     or unenforceability of any part shall not affect the validity or
     enforceability of any remaining part or parts, all of which shall remain in
     full force and effect.  However, the parties agree to substitute any
     invalid or unenforceable provision by valid and enforceable arrangement
     which achieves to the greatest extent possible the financial balance and
     mutual understanding already established between the parties.

SIXTEENTH -  Any dispute, controversy or difference that may arise from the
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interpretation or in connection with the present Agreement or as the compliance
of any other obligations contained herein, shall be submitted to arbitration
held in Barcelona (Spain), in the "Tribunal Arbitral de Barcelona" according to
its rules.  The award rendered in any such arbitration shall be final and
binding upon the parties hereto.

SEVENTEENTH -  The parties agree that the present document is a commercial
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agreement and is ruled by the Clauses contained herein, and shall be governed by
the laws of Spain, by Spanish commercial usage or, in its case, by the Spanish
Civil Code.

In witness whereof, the present Agreement is signed in duplicate in the place
and date first written above.

INSTITUTO GRIFOLS, S.A.                  SERACARE INC.

/s/ Javier Jorba Ribes                   /s/ Barry D. Plost

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                            LIST OF OMITTED ANNEXES

The following Annexes to the Albumin Supply Agreement have been omitted from
this Exhibit and shall be furnished to the Commission upon request:

Annex                    Document
-----                    --------

2                        USA Package Insert

3                        Human Albumin as Raw Material

5                        Shipment Information

6                        Confidential Disclosure Agreement

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                                    ANNEX 1


                                      ***





_________________________
*** Confidential information omitted and filed separately with the Securities
and Exchange Commission.

<PAGE>

                                    ANNEX 4


                             HUMAN ALBUMIN GRIFOLS

                              QUANTITIES AND PRICE

-  The quantities established for the year 1999 will be in the range of *** -
   *** vials per month.

-  Product price:

-        Human Albumin Grifols at *** per gram FOB Barcelona.



_________________________
-  *** Confidential information omitted and filed separately with the
   Securities and Exchange Commission.

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