PURCHASE AGREEMENT

Exhibit 10.28

PURCHASE AGREEMENT

      THIS AGREEMENT is made and entered into this 24th day of August, 2007, by and between SurModics, Inc., a Minnesota corporation, with its principal place of business at 9924 West 74th Street, Eden Prairie, MN 55344 (hereinafter called “Purchaser”), and Vest Mykyng LLC, a Minnesota limited liability company, with its principal place of business at 6138 Arctic Way, Edina, Minnesota 55436 (hereinafter called “Seller”).

      WITNESSETH THAT, WHEREAS:

      A. Seller is the owner of the parcel of land consisting of approximately 4.92 acres, which is described on Exhibit A attached hereto, and all easements, rights of way, privileges, appurtenances, and rights to same belonging to or enuring to the benefit of said parcel of land or its owner (hereinafter called the “Land”) lying and being in the City of Eden Prairie, County of Hennepin, and State of Minnesota.

      B. Seller desires to sell to Purchaser, and Purchaser desires to purchase from Seller, subject to the terms, covenants and conditions hereinafter contained:

      1. The Land, together with any improvements thereon and appurtenances thereto;

      2. All rights appurtenant to the Land as to any roadways adjacent to the Land; and

      3. All right, title and interest of Seller in and to all easements of record benefiting the Land (or the owner or users thereof) over other property, if any (such property hereinafter is collectively called the “Subject Property”).

      NOW, THEREFORE, in consideration of the foregoing, and in consideration of the mutual covenants herein contained, which each of the parties hereto acknowledges as adequate and sufficient, it is hereby agreed as follows:

      1. Purchase and Permitted Encumbrances . Subject to the terms and conditions herein, Seller does hereby agree to sell to Purchaser, and Purchaser does hereby agree to purchase from Seller, the Subject Property, subject only to the following encumbrances (hereinafter called “Permitted Encumbrances”):

      (a) Building, zoning and subdivision ordinances, and State and Federal regulations, subject to the other terms and conditions herein in respect thereto.

      (b) Real estate taxes and installments of special assessments which are not yet due and payable as of the Closing Date. Seller and Purchaser shall allocate/prorate real estate taxes and special assessments (including interest included in such installments) payable in the year of Closing in the manner provided in Subparagraph 12(c) hereof.

      (c) Those easements, encumbrances, and restrictions set forth on Exhibit B and the title commitment provided for herein which are not objected to by Purchaser in connection with Purchaser’s examination of title and survey and made a part hereof and such other easements, encumbrances and restrictions as may be approved or waived by Purchaser pursuant to the terms of this Agreement.

      2. Representations of Seller; “As Is” Purchase . Except as disclosed on Exhibit D attached hereto (“Seller’s Disclosure”) Seller states, warrants and represents as of the date hereof as follows:

      (a) Seller has full right and authority to execute and deliver this Agreement and all documents and instruments required hereunder to be executed and delivered by Seller.

      (b) Neither the entering into of this Agreement nor the consummation of the transaction contemplated hereby will constitute or result in a violation or breach by Seller of any judgment or decree issued against or imposed upon Seller, or of any agreement to which Seller is a party or which binds the Subject Property.

      (c) To Seller’s knowledge, there are no underground storage tanks on the Subject Property.

      (d) Seller is neither a “foreign person” nor a “foreign corporation” (as those terms are defined in Section 1445 of the Internal Revenue Code of 1986, as amended).

      (e) To Seller’s knowledge, there are no wells or private sewage disposal or septic systems on the Subject Property.

      (f) To Seller’s knowledge, no environmental reports have been made or prepared in connection for the Subject Property except those certain reports and correspondence listed in the Disclosure and Disclosure Documents attached hereto as Exhibit D, true and complete copies of which Seller has delivered to Purchaser; provided, however, Seller discloses that certain dumping may have occurred in approximately the early 1980s and believes any contamination in connection therewith was cleaned up in accordance with law and reports may have been generated in connection therewith, copies of which Seller cannot locate in his possession.

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      (g) Seller has received no notice of condemnation of any portion of the Subject Property from any governmental authority.

      (h) Solely for purposes of satisfying the requirements of Minn. Stat. § 115.55, to Seller’s knowledge there is no “individual sewage treatment system” (within the meaning of that statute) on or serving the Subject Property.

      (i) To Seller’s knowledge, there are no actions, suits, agreements or proceedings before any judicial or quasi-judicial body, pending, or to Seller’s knowledge, threatened, against or affecting all or any portion of the Subject Property which would impair Seller’s ability to close the transaction contemplated hereby in accordance with the terms hereof.

      (j) Seller is not in violation of any laws relating to terrorism or money laundering (“Anti-Terrorism Laws”), including Executive Order No. 13224 on Terrorist Financing, effective September 24, 2001 (the “Executive Order”), and the Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001, Public Law 107-56. Seller or, to the knowledge of Seller, one of its agents acting or benefiting in any capacity in connection with the transaction is any of the following:

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      (k) The Seller or, to the knowledge of Seller, any of its agents acting in any capacity in connection with the transaction does not (i) conduct any business or engage in making or receiving any contribution of funds, goods or services to or for the benefit of any person described above, (ii) deal in, or otherwise engage in any transaction relating to, any property or interests in property blocked pursuant to the Executive Order, or (iii) engages in or conspires to engage in any transaction that evades or avoids, or has the purpose of evading or avoiding, or attempts to violate, any of the prohibitions set forth in any Anti-Terrorism Law.

      To the extent any of the above representations or warranties are made to the knowledge of Seller, such representations shall be deemed made only as to the actual knowledge of Sigmund J. Helle without having made any investigation or inquiry except those resulting in the creation of the materials listed on or contained in the documents, if any, listed on Exhibit D.

      Prior to Closing, Seller will give Purchaser prompt written notice of any occurrence that would change the truth of any of the foregoing representations and warranties or any other representation or warranty of Seller herein, if then made. If there is a material adverse change in any of the foregoing representations and warranties prior to Closing, Purchaser will have the right to terminate this Agreement by giving written notice to Seller within ten (10) days after it receives written notice of such material change. If Purchaser so terminates this Agreement, the initial $100,000 Earnest Money Deposit shall be retained by Seller and any Additional Earnest Money Deposit (hereafter defined) shall be returned to Purchaser and neither party shall have further rights or obligations hereunder except for any obligations contained in this Agreement which expressly survive termination.

      PURCHASER ACKNOWLEDGES THAT PURSUANT TO THIS AGREEMENT IT WILL HAVE PRIOR TO CLOSING THE OPPORTUNITY TO PERFORM ALL SUCH TESTS, INVESTIGATIONS AND ANALYSES CONCERNING THE SUBJECT PROPERTY AS IT DEEMS NECESSARY OR DESIRABLE. PURCHASER AGREES THAT EXCEPT FOR THE REPRESENTATIONS AND WARRANTIES OF SELLER EXPRESSLY CONTAINED IN THIS PARAGRAPH 2 AND IN THE CLOSING DOCUMENTS, IN PURCHASING THE SUBJECT PROPERTY, PURCHASER IS NOT RELYING ON ANY REPRESENTATION, WARRANTY OR PROMISE BY OR ON BEHALF OF SELLER CONCERNING THE PROPERTY OR ANY ASPECT THEREOF, INCLUDING, WITHOUT LIMITATION, ANY CONCERNING THE QUALITY, VALUE, PHYSICAL ASPECTS, PROSPECTS, COMPLIANCE WITH LAWS OR CONDITION OF THE SUBJECT PROPERTY, ENVIRONMENTAL OR OTHERWISE, OR THE FITNESS OR SUITABILITY OF THE SUBJECT PROPERTY FOR ANY PARTICULAR USE, AND, EXCEPT FOR THE REPRESENTATIONS AND WARRANTIES EXPRESSLY CONTAINED IN THIS PARAGRAPH 2 AND IN THE CLOSING DOCUMENTS, PURCHASER IS PURCHASING THE SUBJECT PROPERTY BASED UPON PURCHASER’S OWN INSPECTIONS AND EXAMINATIONS THEREOF IN ITS “AS IS” AND “WHERE IS” CONDITION, AND “WITH ALL FAULTS.”

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      3. Representation of Purchaser . Purchaser warrants and represents as of the date hereof as follows:

      (a) Purchaser has full right and authority to execute and deliver this Agreement and all documents and instruments required hereunder to be executed and delivered by Purchaser.

      (b) The consummation of the transactions contemplated by this Agreement will not constitute a default or result in the breach of any term or provision of any contract or written agreement to which Purchaser is a party so as to adversely affect the consummation of such transactions.

      (c) Purchaser is not in violation of any Anti-Terrorism Laws, including the Executive Order, and the Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001, Public Law 107-56.

      (d) Purchaser or, to the knowledge of Purchaser, none of its agents acting or benefiting in any capacity in connection with the transaction is any of the following:

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      (f) The Purchaser or, to the knowledge of Purchaser, any of its agents acting in any capacity in connection with the transaction does not (i) conduct any business or engage in making or receiving any contribution of funds, goods or services to or for the benefit of any Person described above, (ii) deal in, or otherwise engage in any transaction relating to, any property or interests in property blocked pursuant to the Executive Order, or (iii) engages in or conspires to engage in any transaction that evades or avoids, or has the purpose of evading or avoiding, or attempts to violate, any of the prohibitions set forth in any Anti-Terrorism Law.

      4. Purchase Price . Purchaser shall pay to Seller, in consideration for the purchase of the Subject Property, the sum of Three Million Six Hundred Thousand and no/100 Dollars ($3,600,000.00) (the “Purchase Price”). The Purchase Price shall be paid as follows: One Hundred Thousand and 00/100 Dollars ($100,000.00) upon execution of this Agreement (hereinafter called “Earnest Money Deposit”) shall be deposited with Seller by Purchaser. Such initial $100,000.00 Earnest Money Deposit shall be non-refundable to Purchaser; provided, however, it shall be subject to claims of Purchaser in the event this Agreement is terminated by Purchaser pursuant to the provisions of Paragraph 13(A) by reason of Seller’s breach of this Agreement. The balance of said Purchase Price plus or minus (as the case may be) an amount which equals the cumulative result of all cash adjustments and prorations required by this Agreement, shall be payable to Seller on the Date of Closing by means of a wire transfer to be received on the Date of Closing in Seller’s designated bank account. Purchaser and Seller shall each pay one-half of the costs of establishing and maintaining the escrow of the Additional Earnest Money Deposit, if any (described hereafter). In the event of a Closing, all of the Earnest Money Deposit will be credited to the Purchase Price.

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      5. Evidence of Title/Survey . Not later than the date ten (10) days after the date of this Agreement, Seller shall furnish to Purchaser at Seller’s cost, except as hereafter provided, a current commitment for an Owner’s current ALTA policy of title insurance (including a special assessment search) as to the Subject Property issued by Title Company covering the Land provided for herein, and in an amount equal to the Purchase Price for the Subject Property, in which Title Company also indicates its requirements to provide extended coverage over the standard exceptions. Such commitment shall also include copies of all recorded documents referred to in the commitment. Purchaser shall be allowed until that date which is seventeen (17) days after receipt of the commitment examination of title and survey and the making of any objections thereto, said objections to be made in writing or deemed waived. For purposes of this Agreement, Permitted Encumbrances shall not be title objections. If any objections are so made, Seller shall be allowed five (5) days after the notice of objection to make such title marketable. Seller shall not be required to cure title or survey objections. Seller shall pay off and satisfy of record any monetary and mechanic’s liens (including any medical assistance lien) and mortgages against the Subject Property at Closing and shall take such action as is necessary to remove from the commitment the requirement to secure and record an Affidavit showing compliance with the required Notice to the Commissioner of Human Services pursuant to Minn. Stat. 524-801(d) for the Estate of Herliev Helle for the Deed of Distribution to Sigmund J. Helle filed as Document No. 7363899.

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      If title and survey objections are not cured and title is not made marketable all on or before the end of the five (5) day period above described, Purchaser shall by written notice to Seller either:

      (a) Terminate this Agreement, and, in such event, Purchaser shall be entitled to a refund of all of the Additional Earnest Money Deposit (described hereafter), if any, and neither party will have further rights or obligations hereunder except such obligations as expressly survive termination; or

      (b) Waive any uncured objected to defects in title without any reduction in the Purchase Price.

Purchaser will make its election within seven (7) days after expiration of Seller’s five (5) day cure period. A failure by Purchaser to waive its objections within such seven (7) day period pursuant to clause (b) shall be deemed an election to terminate under clause (a).

      Further, not later than the date twenty (20) days after the date of this Agreement, Purchaser shall secure and deliver to Seller (at Purchaser’s sole cost and expense) a current survey of the Subject Property (herein called the “Survey”) prepared by a surveyor licensed in the State of Minnesota and reasonably acceptable to Purchaser, certified to Seller, Purchaser and Title Company and Purchaser’s lender, if any, in a manner satisfactory to Purchaser, by such surveyor as being true, accurate and having been prepared in accordance with the current minimum detail and Table A requirements for an Urban Land Title Survey as jointly established and adopted by the American Land Title Association and the American Congress on Surveying and Mapping, and setting forth: (i) the legal description of the Subject Property; (ii) the location of all improvements thereon; (iii) all boundaries, courses and dimensions of the Land, and the dimensions of said improvements; (iv) all easements, building lines, curb cuts, parking, loading areas, sewage, water, electricity, gas and other utility facilities (together with the recording information concerning the documents creating any easements and building lines); (v) roads and means of ingress and egress to and from the Subject Property to all public roadways; and (vi) the gross square footage of the Subject Property. The Survey shall reveal any encroachments onto the Subject Property from any adjacent property, any encroachments by or from the Subject Property onto any adjacent property, and any violation by any of the improvements on the Subject Property of any building line or easement or restriction affecting the Subject Property. The Survey shall also certify whether or not the Subject Property is in an area identified by an agency or department of the Federal, State or local government as having special flood or mudslide hazards whether or not such identification would require flood insurance under any flood insurance laws and shall state whether the Subject Property includes any area identified or designated by Federal, State or local government as a wetland. Such survey shall be delivered in the form of paper copies and on computer disk form in Auto CADD (latest format).

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      6. Delivery of Possession . Physical possession of the Subject Property shall be delivered to Purchaser on the Date of Closing.

      7. Closing . The Closing of this transaction shall take place at the office of Purchaser’s counsel or other mutually acceptable location in Minneapolis, Minnesota, on the date one (1) year subsequent to the date hereof (herein called the “Date of Closing”). Purchaser may accelerate the date of Closing to a date selected by Purchaser provided Purchaser gives Seller forty (40) days prior written notice of such Closing Date and along with such notice Purchaser delivers to Title Company an additional Six Hundred Thirty Thousand and no/100 Dollars ($630,000.00) as additional Earnest Money Deposit (the “Additional Earnest Money Deposit”). Such Additional Earnest Money Deposit shall be deposited with Old Republic National Title Insurance Company (“Title Company”) by Purchaser, and shall be held by such Title Company in an interest bearing account. Purchaser shall execute the W-9 form in connection therewith. Any interest earned on said Additional Earnest Money Deposit, if any, shall become a part of the Additional Earnest Money Deposit. Purchaser shall bear the risk of loss with respect to the Additional Earnest Money Deposit. In the event such notice of acceleration is given, the Purchase Price will escalate by Six Hundred Thirty Thousand and no/100 Dollars ($630,000.00) to Four Million Two Hundred Thirty Thousand and no/100 Dollars ($4,230,000.00). Notwithstanding the above, Seller may accelerate the date of Closing to a date after the date forty-five (45) days after the date of this Agreement and at least twenty (20) days subsequent to Seller’s notice of acceleration of the date of Closing; provided, however, if Seller accelerates the Closing there shall be no increase in the Purchase Price.

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      8. Documents to be Delivered at Closing . At Closing, Seller shall deliver to Purchaser:

      (i) Limited Warranty Deed conveying to Purchaser fee title to the Subject Property, subject only to Permitted Encumbrances and such Deed shall contain a representation by Seller that Seller does not know of any wells on the Subject Property unless Seller provides a well disclosure certificate with respect to any wells of which Seller has knowledge;

      (ii) “FIRPTA” affidavit in the form of Exhibit D attached hereto and made a part hereof;

      (iii) Seller’s Affidavit in the form of Exhibit G attached hereto.

      (iv) Such other documents and instruments as may reasonably be required to carry out the terms of this Agreement.

      (v) Taxpayer Identification and/or Federal I.D. Number Certificate as required by Title Company.

Purchaser shall deliver to Seller the following instruments and documents:

      (a) The Purchase Price in accordance with Paragraph 4 hereof

      (b) Such other documents and instruments as may reasonably be required to carry out the terms of this Agreement.

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At Closing, Seller and Purchaser shall jointly deliver a closing statement to each other, and Purchaser shall provide the certificate of real estate value, if any is required in connection with the filing of said Limited Warranty Deed.

      9. Purchaser’s Entry Prior to Closing . At any time prior to the earlier of (a) Closing or (b) the date of termination of this Agreement, Purchaser shall have the right at reasonable times to enter upon the Subject Property solely to examine, survey, inspect and to take soil boring tests or tests for environmental contamination at Purchaser’s sole risk, cost and expense in order to determine the characteristics of the Subject Property. Purchaser shall pay all costs of such survey, inspection, soil borings and tests. Purchaser shall notify Seller at least 48 hours prior to each entry for such purposes so that Seller may attend such activity. Purchaser shall promptly provide to Seller copies of all reports of its examinations, surveys, inspections and tests without cost to Seller. Purchaser shall also be responsible for damages suffered by Seller arising out of Purchaser’s breach of the provisions of this Paragraph 9.

      Purchaser hereby agrees to defend, indemnify and save Seller, its agents, employees and contractors harmless from all liability, damage, cost and expense (including, but not limited to, reasonable attorney’s fees) in connection with all claims, suits, actions of every name, kind and description brought against Seller, its agents, employees or contractors by any person or entity to the extent arising or alleged to have arisen out of the acts or omissions of Purchaser, its agents or employees in exercising its rights under the right of entry granted herein unless and except to the extent the same arise out of the negligence or wrongful act of Seller, its agents, employees and contractors. Purchaser’s obligation to indemnify, defend and save Seller harmless shall survive Closing or termination of this Agreement.

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      10. Condition Allowing Termination by Purchaser . If any of the following conditions (which shall be for Purchaser’s benefit and may be waived by Purchaser) occur:

      (a) Purchaser in its sole discretion disapproves the condition of the soil, title, survey or environmental issues relating to the Subject Property or its potential found or determined to exist, as deemed appropriate by Purchaser, in respect to the Subject Property whether found during its due diligence effort or otherwise; or Purchaser determines that utilities, including electricity, storm sewer, sanitary sewer, gas and water utilities do not exist or are insufficient in capacity to serve Purchaser’s proposed improvements under current zoning relating to the Subject Property;

then, and in any such event, Purchaser shall have the right to terminate this Agreement by written notice to Seller given on or before the date forty-five (45) days after the date hereof, and on such termination all payments of the Additional Earnest Money Deposit described in Paragraph 7, if any, received by Title Company pursuant to this Agreement together with accrued interest shall be paid by Title Company to Purchaser.

      11. Brokerage Fees . Purchaser represents that Purchaser is represented by Northstar Partners as Purchaser’s broker in connection with the transaction contemplated hereby. Purchaser and Seller each represent and warrant to the other that (except as to the fees payable by Purchaser to the party or parties identified in the preceding sentence of this Paragraph) they have not incurred any obligation or liability, contingent or otherwise, for brokerage or finder’s fee or agent’s commissions or other like payment in connection with this Agreement or the transaction contemplated hereby, and Purchaser and Seller each agree to indemnify, defend and hold the other harmless against and in respect of any such obligation and liability based in any way upon any other agreements, arrangements or understandings made or claimed to have been made by the indemnifying party with any third person. Purchaser will pay all fees payable to Northstar Partners and its agents and co-brokers.

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      12. Costs . The costs to be incurred in closing the transaction contemplated by this Agreement shall be allocated to Seller and Purchaser in the event of Closing in the following manner:

      (a) Seller shall pay for any transfer, excise or deed tax to be incurred in connection with the conveyance or in recording the Limited Warranty Deed to be delivered by Seller on the Date of Closing.

      (b) Purchaser shall pay for the recording fees incurred in recording the Limited Warranty Deed to be delivered by Seller to Purchaser on the Date of Closing.

      (c) Seller shall pay all real estate taxes excluding, except as otherwise provided, special assessments certified for payment therewith, payable in respect to the Subject Property in the calendar year prior to the calendar year in which Closing occurs and prior years. Further, all levied and pending special assessments as of the date of this Agreement shall be paid in full by Seller at or before Closing. Real estate taxes in respect to the Subject Property (other than special assessments, which shall be paid by Seller to the extent provided in the immediately preceding sentence) due and payable in the calendar year in which Closing occurs shall be prorated between Seller and Purchaser, with Purchaser paying that percentage equal to the number of days in such year subsequent to the Tax Date divided by 365 and Seller paying the balance. For purposes of this subparagraph (c), the Tax Date shall be deemed to be the day immediately prior to the Date of Closing. If on the Date of Closing the current year’s taxes are not available, the proration and allocation for such tax parcels shall be based on the previous year’s payment and an adjustment shall be made in cash on the date ten (10) days after the date when the current year’s taxes and installments of special assessments are known. Special assessments first pending after the date of this Agreement shall be paid by Purchaser. In the event Seller has paid prior to Closing installments (including any interest allocable thereto) of special assessments which are Purchaser’s responsibility herein, Purchaser shall reimburse Seller for same at Closing.

      (d) Seller shall pay for the State Deed Tax and the cost of furnishing a title commitment to Purchaser in the manner required by the provisions of Paragraph 5 hereof, and Purchaser shall pay for the Survey and the cost of any title insurance policy and all endorsements issued in connection therewith.

      (e) Purchaser and Seller shall each pay one-half (1/2) of all costs of establishing and maintaining the escrow of the Earnest Money Deposit.

      (f) Seller and Purchaser shall each pay one-half (1/2) of any closing fee required by Title Company to close the transaction contemplated by this Agreement.

      (g) Seller and Purchaser shall each pay all of the costs and fees charged by their respective legal counsel.

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13. Remedies .

      A. In the event Seller shall default in any material respect in the performance of any of its obligations hereunder prior to Closing and continues in default for a period of thirty (30) days after written notice of such default from Purchaser to Seller, Purchaser shall have the right to terminate this Agreement, in which event Escrow Agent shall return to Purchaser the entire Earnest Money Deposit and all payments theretofore made to or for the benefit of Seller. Notwithstanding anything contained in this Agreement to the contrary, such right and remedy of Purchaser shall not deprive Purchaser of the right of commencing legal proceedings for damages. Purchaser shall also have the option of enforcing specific performance of this Agreement, provided this Agreement has not been terminated as aforesaid and provided action to enforce such specific performance is commenced within six (6) months after any such right of action arises.

      B. In the event Purchaser shall default in any material respect in the performance of any of its obligations hereunder other than obligations to close and continues in default for a period of thirty (30) days after written notice of such default from Seller to Purchaser, Seller shall have the right to terminate this Agreement prior to the required Closing Date in accordance with applicable Minnesota law, in which event Seller shall be entitled to retain, free of any claim by Purchaser, the initial $100,000.00 Earnest Money Deposit as non-refundable Earnest Money Deposit and as liquidated damages (except for Purchaser’s obligations under Paragraphs 9 and 26 hereof) and not as a penalty. Purchaser agrees that, in the event of such a default by Purchaser hereunder, Seller’s damages would be difficult or impossible to determine and that an amount equal to the initial $100,000.00 Earnest Money Deposit and such other payments by Purchaser to Seller is a fair estimate thereof.

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