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| Seventh Amendment to Loan documents |   |
|-------------------------------------|--------|

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| WITNESS / ATTEST:                                                 |   | STRATEGIC DIAGNOSTICS INC.       |
|-------------------------------------------------------------------|--------|----------------------------------|
|                                                              |   |                             |   |
| /s/ Hillary R. Lucas                                              |   | By:                              | /s/ Stanley Franczkowski |
|                                                              |   |                             | (SEAL) |
| Print Name: Hillary R. Lucas                                      |   | Print Name: Stanley Franczkowski |
|                                                              |   |                             |   |
| Title:                                                            |   | Title: CFO                       |
| (Include title only if an officer of entity signing to the right) |   |                             |   |

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|   |   | PNC BANK, DELAWARE |
|--------|--------|--------------------|
|   |   |               |   |
|   |   | By:                | /s/ Warren Engle |
|   |   |               | (SEAL) |
|   |   |               | Warren Engle |
|   |   |               | Senior Vice President |

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|   | 3.                                                                                                                                                                                               | The 2001 Term Note is hereby amended as follows:                                                                                                                                                                         |
|--------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|   |                                                                                                                                                                                             |                                                                                                                                                                                                                     |   |   |
|   |                                                                                                                                                                                             | (a)                                                                                                                                                                                                                      | Section 1 is amended by amending and restating the first sentence to read in full as follows: |
|   |                                                                                                                                                                                             |                                                                                                                                                                                                                     |   |   |
|   |                                                                                                                                                                                             |                                                                                                                                                                                                                     | “1. Rate of Interest. Amounts outstanding under this Note will bear interest at a rate per annum equal to the sum of (A) the Euro-Rate plus (B) one hundred (100) basis points (1.0%) for the applicable Euro-Rate Interest Period.” |   |
|   |                                                                                                                                                                                             |                                                                                                                                                                                                                     |   |   |
|   |                                                                                                                                                                                             | (b)                                                                                                                                                                                                                      | Section 1 is further amended by amending the first sentence of the definition of the term “Base Rate” to read in full as follows: |
|   |                                                                                                                                                                                             |                                                                                                                                                                                                                     |   |   |
|   |                                                                                                                                                                                             |                                                                                                                                                                                                                     | “ “Base Rate” means a rate of interest per annum which is at all times equal to the sum of (A) the Prime Rate minus (B) one hundred (100) basis points (1.0%).” |   |
|   |                                                                                                                                                                                             |                                                                                                                                                                                                                     |   |   |
| C.     | Conditions to Effectiveness of Amendment: The Bank’s willingness to agree to the amendments set forth in this Amendment are subject to the prior satisfaction of the following conditions: |
|   |                                                                                                                                                                                             |                                                                                                                                                                                                                     |   |   |
|   | 1.                                                                                                                                                                                               | Execution by all parties and delivery to the Bank of this Amendment, and execution by the Borrower and delivery to the Bank of a Term Note evidencing the 2007 Term Loan in form and substance satisfactory to the Bank. |

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| A.     | The “Loan Documents” that are the subject of this Amendment include the following (as any of the foregoing have previously been amended, modified or otherwise supplemented): |
|--------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 1.                                                                                                                                                                                        | Loan Agreement dated as of May 5, 2000, as amended by an Amendment to Loan Documents dated as of December 13, 2001, a Second Amendment to Loan Documents dated as of April 25, 2002, a Third Amendment to Loan Documents dated as of October 24, 2002, a Fourth Amendment to Loan Documents dated as of February 11, 2003, a Fifth Amendment to Loan Documents dated as of February 16, 2004 and a Sixth Amendment to Loan Documents dated as of September 16, 2005 (the “Loan Agreement”) |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 2.                                                                                                                                                                                        | Committed Line of Credit Note dated May 5, 2000 in the maximum principal amount of $5,000,000.00 (the “Line of Credit Note”) |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 3.                                                                                                                                                                                        | Term Note B dated December 13, 2001 in the original principal amount of $1,500,000 (the “2001 Term Note”) |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 4.                                                                                                                                                                                        | Working Cash®, Line of Credit, Investment Sweep Rider dated May 5, 2000 |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 5.                                                                                                                                                                                        | Borrowing Base Rider dated May 5, 2000 (the “Borrowing Base Rider”) |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 6.                                                                                                                                                                                        | Mortgage, Assignment of Rents, Security Agreement Fixture Filing dated May 5, 2000 |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 7.                                                                                                                                                                                        | Assignment of Rents and Leases dated May 5, 2000 |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 8.                                                                                                                                                                                        | Mortgage, Assignment of Rents, Security Agreement and Fixture Filing dated December 13, 2001 |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 9.                                                                                                                                                                                        | Security Agreement dated May 5, 2000 |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 10.                                                                                                                                                                                       | Patent Security Agreement dated May 5, 2000 |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 11.                                                                                                                                                                                       | Trademark Security Agreement dated May 5, 2000 |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 12.                                                                                                                                                                                       | Rider to Security Rider – Patents dated May 5, 2000 |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 13.                                                                                                                                                                                       | Rider to Security Rider – Trademarks dated May 5, 2000 |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 14.                                                                                                                                                                                       | All other documents, instruments, agreements, and certificates executed and delivered in connection with the Loan Documents listed in this Section A. |
|   |                                                                                                                                                                                      |   |   |   |   |
| B.     | The Loan Documents are amended as follows:                                                                                                                                                |
|   |                                                                                                                                                                                      |   |   |   |   |
|   | 1.                                                                                                                                                                                        | The Expiration Date, as set forth in the Line of Credit Note and the Loan Agreement, is hereby extended from August 31, 2007 to August 31, 2008, effective September 1, 2007. |

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|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |   |
|--------|--------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------|--------|
|   | 2.     | The Loan Agreement is hereby amended as follows, effective August 10, 2007:                                                                                                                |
|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
|   |   | (a)                                                                                                                                                                                        | The first sentence of Section 1 is amended and restated to read in full as follows:                                                                                                                                                                                                                                                                                                                                                                                                           |
|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
|   |   |                                                                                                                                                                                       | “The Bank has made or may make one or more loans to the Borrower, including without limitation a $5,000,000 Working Cash ® line of credit (the “Line of Credit”), a term loan with an original principal balance of $1,500,000 (the “2001 Term Loan”) and a term loan with an original principal balance of $2,000,000 (the “2007 Term Loan” and, collectively with the Line of Credit and the 2001 Term Loan, the “Loan”).” |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
|   |   | (b)                                                                                                                                                                                        | Section 1.1. Borrowing Base, which requires that Borrowings under the Line of Credit shall be limited to a borrowing base and that the Borrower will submit Borrowing Base certificates, is deleted in its entirety.                                                                                                                                                                                                                                                                          |
|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
|   |   | (c)                                                                                                                                                                                        | As used in the Loan Agreement, the defined term the “Loan” shall mean the following:                                                                                                                                                                                                                                                                                                                                                                                              |
|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
|   |   |                                                                                                                                                                                       | i.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | In Section 1.2 of the Loan Agreement, the “Loan” shall refer to the Line of Credit only.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
|   |   |                                                                                                                                                                                       | ii.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | Other than in Section 1.2, the “Loan” shall refer to the Line of Credit, the 2001 Term Loan and the 2007 Term Loan.                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |   |
|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
|   |   | (d)                                                                                                                                                                                        | The first sentence of Section 1.2 is amended and restated to read in full as follows:                                                                                                                                                                                                                                                                                                                                                                                                         |
|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | “The Line of Credit will accrue interest at rates equal to the one month LIBOR (as defined in the Note evidencing the Line of Credit) plus the Applicable Margin, and interest on each of the 2001 Term Loan and the 2007 Term Loan will be charged at the rates, and be payable at the dates and times, set forth in the Note evidencing each of the respective Term Loans; the Note evidencing the 2007 Term Loan will also contain a prepayment cost recovery provision requiring a payment to the Bank equal to the losses incurred by the Bank as a result of such prepayment.” |   |
|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
|   |   | (e)                                                                                                                                                                                        | As used in the Loan Agreement, the defined term the “Term Loan” shall mean the 2001 Term Loan and the 2007 Term Loan.                                                                                                                                                                                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|   |   |                                                                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |
|   |   | (f)       The Applicable Margin chart contained in Section 1.2 of the Loan Agreement is hereby amended and restated in its entirety to read as follows: |

|   | Ratio of FundedDebt to EBITDA                |   | Applicable MarginLine of Credit |   | Applicable MarginTerm Loan B |   |
|--------|----------------------------------------------|--------|---------------------------------|--------|------------------------------|--------|
|   |                                         |   |                            |   |                         |   |
|   | ≥3.00:1.00                             |   | 225 basis points                |   | 275 basis points             |   |
|   | <3:00≥2.75                          |   | 200 basis points                |   | 200 basis points             |   |
|   | <2.75≥2.50                          |   | 175 basis points                |   | 175 basis points             |   |
|   | <2.50≥2.25                          |   | 150 basis points                |   | 150 basis points             |   |
|   |       <2.25 |   | 100 basis points                |   | 100 basis points             |   |

|   |   |                                                                                                                                                                                                                |   |   |   |
|--------|--------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------|--------|--------|
|   |   | (g)       Subsection (iii) of Section 4.2., which requires that the Borrower furnish monthly accounts receivable and accounts payable aging reports, is deleted in its entirety. |