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                                                           Exhibit 10.6

              The securities represented hereby have not been registered
         under the Securities Act of 1933, as amended, or any state securities
         laws and neither the securities nor any interest therein may be
         offered, sold, transferred, pledged or otherwise disposed of except
         pursuant to an effective registration statement under such Act and
         such laws or an exemption from registration under such Act and such
         laws which, in the opinion of counsel for the holder, which
         counsel and opinion are reasonably satisfactory to counsel for this
         corporation, is available.


                                      NOTE

$200,000.00                                                February 16, 2001


         For value received, the undersigned, SERACARE, INC., a Delaware
corporation having an address at 1925 Century Park East, Suite 1970, Los
Angeles, Ca 90067 (the "BORROWER"), hereby promises to pay to the order of
Dr. Nelson Teng, 24 Bluebell Lane, Hillsborough, CA 94010 (the "PAYEE"), the
principal sum of Two Hundred Thousand Dollars ($200,000.00), on March 30,
2001, together with all accrued interest through and including the date of
payment (the "INITIAL MATURITY DATE"). At the option of the Borrower, the
Maturity Date may be extended through and until May 14, 2001 (the "FINAL
MATURITY DATE"). Interest shall be payable at a rate per annum (computed for
actual days elapsed on the basis of a 365-day year) of twelve percent
(12.0%). The Borrower may prepay this Note at any time prior to the due date
hereof, in full, without premium or penalty.

         Payments of both principal and interest on this Note are to be
made at 24 Bluebell Lane, Hillsborough, CA 94010, or such other place as the
holder hereof shall designate to the Borrower in writing, in lawful money of
the United States of America in immediately available funds.

         The Borrower shall pay reasonable costs and expenses of collection,
including, without limitation, reasonable attorneys' fees and disbursements
in the event that any action ,suit or proceeding is brought by the holder
hereof to collect this Note and either the holder obtains a judgment in its
favor that is not appealed from or is upheld on appeal, or such action, suit
or proceeding is settled with any sum due and owing to the holder as a result
of such settlement.

         THIS NOTE SHALL BE GOVERNED BY, AND CONSTRUED AND ENFORCED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF CALIFORNIA WITHOUT REGARD TO ITS
RULES PERTAINING TO CONFLICT OF LAWS.


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         THE BORROWER IRREVOCABLY CONSENTS THAT ANY LEGAL ACTION OR
PROCEEDING AGAINST IT UNDER, ARISING OUT OF OR IN ANY MANNER RELATING TO THIS
NOTE MAY BE BROUGHT IN ANY COURT OF THE STATE OF NEW YORK, COUNTY OF NEW
YORK, OR IN THE UNITED STATES DISTRICT COURT FOR THE STATE OF NEW YORK OR IN
THE STATE OF CALIFORNIA, OR IN THE UNITED STATES DISTRICT COURT FOR THE STATE
OF CALIFORNIA. THE BORROWER, BY THE EXECUTION AND DELIVERY OF THIS NOTE,
EXPRESSLY AND IRREVOCABLY ASSENTS AND SUBMITS TO THE PERSONAL JURISDICTION OF
ANY OF SUCH COURT IN ANY SUCH ACTION OR PROCEEDING. BY ITS ACCEPTANCE OF THIS
NOTE BY THE HOLDER AND BY THE EXECUTION HEREOF BY THE BORROWER, EACH AGREES
THAT ANY AND ALL LEGAL ACTION RELATING TO THIS NOTE SHALL BE BROUGHT, AND
MAINTAINED, ONLY IN SUCH COURTS. THE BORROWER FURTHER IRREVOCABLY CONSENTS TO
THE SERVICE OF ANY COMPLAINT, SUMMONS, NOTICE OR OTHER PROCESS RELATING TO
ANY SUCH ACTION OR PROCEEDING BY DELIVERY THEREOF TO IT AT THE ADDRESS SET
FORTH ABOVE OR SUCH OTHER ADDRESS AS THE BORROWER SHALL HAVE THERETOFORE
NOTIFIED THE HOLDER HEREOF IN WRITING OR IN ANY OTHER MANNER PERMITTED BY
LAW. IN THE EVENT SERVICE ON THE BORROWER IS EFFECTED AS SET FORTH IN THE
PRECEDING SENTENCE, THE BORROWER HEREBY EXPRESSLY AND IRREVOCABLY WAIVES ANY
CLAIM OR DEFENSE IN ANY SUCH ACTION OR PROCEEDING BASED ON ANY ALLEGED LACK
OF PERSONAL JURISDICTION, IMPROPER VENUE, FORUM NON CONVENIENS, OR ANY
SIMILAR BASIS.

                                       SERACARE, INC.

                                       By: /s/Jerry L. Burdick
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