Exhibit 10.66

# CHANGE IN CONTROL
AGREEMENT

THIS
AGREEMENT is entered into this 18th day of January, 2002, by and between
PENTAPURE, a Minnesota corporation (the Company) and Andrew Rensink, a
resident of Minnesota (Executive).

BACKGROUND

Executive
is serving as Vice President of Operations of the Company. The parties desire to enter
into a formal employment agreement with respect to the continued employment or employment
security of Executive in the event of a change of control, or in the ownership of the
Company.

TERMS AND CONDITIONS

In
consideration of the premises and the mutual covenants and agreements set forth below,
the parties agree as follows:

1.)     EMPLOYMENT.
Executive agrees to serve as Vice President of Operations for           the Company, for
the term of this Agreement, subject to the terms set forth in           this Agreement
and the provisions of the Bylaws of the Company. During his           employment,
Executive shall devote his effort and attention on a full-time           basis, to the
performance of the duties required of him as an executive of the           Company.

2.)     CONSIDERATION.
As consideration for the Company providing this benefit to           Executive and as a
condition of Executive receiving the benefits set forth in           this Agreement,
Executive agrees to sign and be subject to the obligations and           restrictions of
the Agreement attached hereto and incorporated herein as           Exhibit A.

3.)     DEFINITIONS.
For purposes of this Agreement, the following definitions           shall apply:

| | (1) |  | The
Board shall mean the Board of Directors of the Company.
| | --- |  | -------------------------------------------------------------

| | (2) |  | The
Incumbent Board shall mean the members of the Board as of the date of this
Agreement and any person becoming a member of the Board hereafter whose
election, or nomination for election by the Companys shareholders, was
approved by a vote of at least a majority of the directors then comprising the
Incumbent Board (other than an election or nomination of an individual whose
initial assumption of office is in connection with an actual or threatened
election contest relating to the election of the directors of the Company).
| | --- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | (3) |  | Change
in Control shall mean:
| | --- |  | -------------------------------

| |  | a. |  | The acquisition
(other than from the Company) by any person, entity or group, within
the meaning of Section 13(d)(3) or l4(d)(2) of the Exchange Act (excluding, for
this purpose, any employee benefit plan of the Company or its subsidiaries which
acquires beneficial ownership of voting securities of the Company) of beneficial
ownership (within the meaning of Rule 13d-3 promulgated under the Exchange Act)
of 51% or
| |  | -- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



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| | more of either
the then outstanding shares of Common Stock or the combined voting power of the
Companys then outstanding voting securities entitled to vote generally in
the election of directors: or
| | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| |  | b. |  | The failure for
any reason of individuals who constitute the Incumbent Board to continue to
constitute at least a majority of the Board; or
| |  | -- |  | -------------------------------------------------------------------------------------------------------------------------------------------

| |  | c. |  | Approval by the
stockholders of the Company of a reorganization, merger, consolidation, in each
case, with respect to which the shares of the Company voting stock outstanding
immediately prior to such reorganization, merger or consolidation do not
constitute or become exchanged for or converted into more than 51% of the
combined voting power entitled to vote generally in the election of directors of
the reorganized, merged or consolidated companys then outstanding voting
securities, or a liquidation or dissolution of the Company or of the sale of all
or substantially all of the assets of the Company.
| |  | -- |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

(4)     Good
Reason shall mean:

| |  | a. |  | The assignment
to Executive of any duties inconsistent in any respect with Executives
position (including status, authority, responsibilities, offices, titles and
reporting requirements), authority, duties or responsibilities or any other
action by the Company which results in a diminution in such position, authority,
duties or responsibilities excluding for this purpose any action taken with the
consent of Executive and any isolated, insubstantial and inadvertent action not
taken in bad faith and which is remedied by the Company promptly after receipt
of notice of such action given by Executive;
| |  | -- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| |  | b. |  | A
reduction in the overall level of Executives compensation or benefits;
| |  | -- |  | -------------------------------------------------------------------------

| |  | c. |  | The
Companys requiring Executive to be based at any office or location outside
of the State of Minnesota except for travel reasonably required in the
performance of Executives responsibilities;
| |  | -- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| |  | d. |  | Any purported
termination by the Company of Executives employment otherwise than as
expressly permitted by this Agreement; or
| |  | -- |  | ------------------------------------------------------------------------------------------------------------------------------

| |  | e. |  | Any failure by
the Company to comply with and satisfy paragraph 5 below.
| |  | -- |  | ------------------------------------------------------------------------

(5)      Current
Total Annual Compensation shall be the total of the following amounts:

| |  | a. |  | the greater of
(i) Executives Base Salary for the calendar year in which his
employment terminates or (ii) such salary for the calendar year prior
| |  | -- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------

| |  | b. |  | to the year of
such termination; and (B) the greater of (i) any total amount that became
payable to Executive under the Bonus Plan during the calendar year prior to the
calendar year in which his employment terminates, and (ii) the maximum
amount to which Executive would be paid for the calendar year in which his
employment terminates as if all
| |  | -- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

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| | Plan criteria
had been or are met, regardless of when such amounts are actually to be paid.
Any longer term Bonus Plan payments are to be accelerated and included within
the meaning of this definition.
| | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | (6) |  | The
Exchange Act shall mean the Securities Exchange Act of 1934, as
          amended
| | --- |  | ---------------------------------------------------------------------------------------

| | (7) |  | Cause shall be defined solely as (i) Executives
defalcation or misappropriation of funds or property of the Company, or the
commission of any other illegal act in the course of his employment with the
Company which, in the reasonable judgment of the Board of Directors, has a
material adverse financial effect on the Company or on Executives ongoing
abilities to carry out his duties under this Agreement;
(ii) Executives conviction of a felony or of any crime involving
moral turpitude, and affirmance of such conviction following the exhaustion of
any appeals; (iii) refusal of Executive to substantially perform all of his
duties and responsibilities, or Executives persistent neglect of duty or
chronic unapproved absenteeism (other than for a temporary or permanent
disability), which remains uncured following thirty days after written notice of
such alleged Cause by the Board of Directors; or (iv) any material and
substantial breach by Executive of other terms and conditions of this Agreement,
which, in the reasonable judgment of the Board of Directors, has a material
adverse financial effect on the Company or on Executives ongoing abilities
to carry out his duties under this Agreement and which remains uncured following
thirty days after written notice of such alleged Cause by the Board of
Directors.
| | --- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | (8) |  | Effective
Date shall mean the date the Companys Board of Directors approves
this Agreement.
| | --- |  | ----------------------------------------------------------------------------------------------

4.)     EFFECT
OF TERMINATION DUE TO A CHANGE OF CONTROL/TERMINATION PAYMENTS.

| | (a)        If Executives employment is
terminated or Executive elects to terminate his employment for Good Reason,
either occurring within two years after any Change of Control of the Company,
the Executive shall be entitled to a payment equal to 18 months of
Executives Current Total Annual Compensation. This payment shall be made
to Executive either as a lump sum within 30 business days after his termination,
or if the Executive so elects, in installments of his choosing.
| | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | (b)      In addition to the payments referred to
herein, Executive shall be entitled to the following upon his involuntary
termination or his election to terminate for Good Reason either occurring within
two years of and as part of a Change in Control:
| | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | The health care
(including medical and dental) and life insurance benefits coverage provided to
Executive at his date of termination shall be continued at the same level and in
the same manner as if his employment had not terminated (subject to the
customary changes in such coverages if Executive reaches age 65 or similar
events), beginning on the date of such termination and ending on the date
eighteen months from the date of termination, followed by COBRA election rights.
Any additional coverages Executive had at termination, including dependent
coverage, will also be continued for such period on the same terms. Any costs
Executive was paying for such coverages at the time of termination shall
continue to be paid by Executive. If the terms of any benefit plan
referred
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| | to in this
section do not permit continued participation by Executive, then the Company
will arrange for other coverage providing substantially similar benefits at the
same contribution level of Executive.
| | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | (c)     The
Executive shall also be entitled to the payments and benefit continuation in
paragraphs (a) and (b) herein, if Executives employment is terminated by
the Company, other than for Cause, at the request of or pursuant to an agreement
with a third party who has taken steps reasonably calculated to effect a Change
in Control, or otherwise in connection with or in anticipation of a Change in
Control any of which occurs after the Effective Date of this Agreement.
| | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

5.)
     SUCCESSORS; BINDING AGREEMENT; ASSIGNMENT.
The Company shall require any successor (whether direct or indirect, by
purchase, merger, consolidation or otherwise) to all or substantially all of the
business or assets of the Company to expressly assume and agree in writing to
perform this Agreement in the same manner and to the same extent that the
Company would be required to perform it if no such succession had taken place.
The Executive must be given the same position with the same authority, powers
and responsibilities with respect to the subsidiary or subdivision which
operates the business of the Company as it exists on the date of such business
combination. Failure of the Company to obtain such express assumption and
agreement at or prior to the effectiveness of any such succession shall be a
breach of this Agreement and shall entitle the Employee to compensation and
benefits from the Company in the same amount and on the same terms to which the
Employee would be entitled hereunder if the Company terminated the
Employees employment without Cause pursuant to a Change of Control, except
that all options will be immediately vested. For purposes of implementing the
foregoing, the date on which any such succession becomes effective shall be
deemed the date of termination. As used in this Agreement,  the
Company shall mean the Company as hereinbefore defined and any successor
to its business or assets as aforesaid which assumes and agrees to perform this
Agreement by operation of law, or otherwise. The Company may not assign this
Agreement, (i) except in connection with, and to the acquiror of, all or
substantially all of the business or assets of the Company, and then only if
such acquiror expressly assumes and agrees in writing to perform this Agreement
as provided in this paragraph, and (ii) except in connection with the
Company becoming a wholly-owned subsidiary in which event the Company may assign
this Agreement and all of the Companys rights and obligations hereunder
its parent company. The Executive may not assign his rights or delegate his
duties or obligations under this Agreement.

6.)
     NOTICES. Any notice or other communications
under this Agreement shall be in writing, signed by the party making the same,
and shall be delivered personally or sent by certified or registered mail,
postage prepaid, addressed as follows:

|If to Executive:   | Andrew Rensink                                               
|------------------ | -------------------------------------------------------------
|If to the Company: | PentaPure Incorporated 1000 Apollo Road Eagan, MN  55121-2240

or to such other address or
agent as may hereafter be designated by either party hereto. All such notices
shall be deemed given on the date personally delivered or mailed.

7.)     FULL
SETTLEMENT AND LEGAL EXPENSES. The Companys obligation to make the
payments provided for in this Agreement and otherwise to perform its obligations
hereunder shall not

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be affected by any set-off
(except for loans or other amounts owed by Executive to the Company)
counter-claim, recoupment, defense or other claim, right or action which the
Company may have against Executive or others. In no event shall Executive be
obligated to seek other employment or take any other action by way of mitigation
of the amounts payable to Executive under any of the provisions of this
Agreement. No remuneration paid or payable to Executive from subsequent
employment the Executive may obtain will be offset against the Companys
obligations for payment under this Agreement. The prevailing party shall be
entitled to recover all legal fees and expenses which such party may reasonably
incur as a result of any legal proceeding relating to the validity,
enforceability, or breach of, or liability under, any provision of this
Agreement or any guarantee of performance (including as a result of any contest
by Executive about the amount of any payment pursuant to paragraph 4 of
this Agreement), plus in each case interest at the applicable Federal Rate
provided for in Section 7872(f)(2) of the Code.

8.)     GOVERNING
LAW AND JURISDICTION. This Agreement shall be interpreted and enforced in
accordance with the laws of the State of Minnesota. Courts in the State of
Minnesota shall be the exclusive forum for resolving any disagreements or
disputes relating to this Agreement.

9.)     SEVERABILITY.
Whenever possible, each provision of this Agreement shall be interpreted in such
manner as to be effective and valid, but if any one or more of the provisions
contained in this Agreement shall be invalid, illegal or unenforceable in any
respect for any reason, the validity, legality and enforceability of any such
provisions in every other respect and of the remaining provisions of this
Agreement shall not be in any way impaired.

10.)     ENTIRE
AGREEMENT. This Agreement (including all Exhibits) contains the entire
agreement of the parties with respect to the subject matter contained in this
Agreement. There are no restrictions, promises, covenants, or undertakings
between the Company and Executive, other than those expressly set forth in this
Agreement. This Agreement supersedes all prior agreements and understandings
between the parties. This Agreement may not be amended, discharged, waived, or
modified except in writing executed by the parties.

11.)     COUNTERPARTS
AND FAX SIGN. This Agreement may be executed in counterparts, and each such
duly executed counterpart shall be of the same validity, force and effect as the
original. Facsimile copies of signatures shall constitute valid and binding
obligations of the signing party once delivered by facsimile to the other party.

IN
WITNESS WHEREOF, the undersigned have executed this Agreement as of the day and
year first above written.

|                        | PENTAPURE (CORPORATE SEAL)        
|----------------------- | ----------------------------------
|Date:  January 28, 2002 | By: /s/ James J. Caronari Its: CEO

|                        | EXECUTIVE:          
|----------------------- | --------------------
|Date:  January 28, 2002 | By: /s/ Andy Rensink

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