Exhibit 2.6

[English Translation – Original Document in German]

SHARE PURCHASE AND TRANSFER AGREEMENT

between

The persons under 2. to 7. above are hereinafter also referred to as the „ Sellers ” and each of them as a “ Seller ”.

The persons under 1. to 7. above are hereinafter also referred to as the „ Parties ” and each of them as a “ Party ” -

TABLE OF CONTENTS

WHEREAS

The Purchaser intends to acquire 100% of the shares in QUANTRON GmbH, a company registered with the commercial register at the local court of Kleve under registration number HR B 2541 having its registered office in Tiergartenstrasse 64, 47533 Kleve (hereinafter referred to as the “ Company ”). The Sellers currently hold all shares in the Company´s share capital totalling EUR 670.000,00 and intend to sell all shares owned by them, consisting of 100% of the share capital of the Company. The Company owns 100% of the outstanding shares of Quantron Inc., a company existing under the laws of Massachusetts, USA, having its registered office in Fitchburg, MA 01420 (USA).

Furthermore, the Purchaser intends to acquire the silent partnerships in Quantron GmbH held by the First Seller, the Fourth Seller and the Fifth Seller. The nominal value of these silent partnership interests totals EUR [ * ], before interest.

NOW, THEREFORE, the Parties agree as follows:

1.              INTERPRETATIONS

1.1           Definitions

For the purpose of this Agreement including its annexes and appendices, the following terms shall have the following meanings:

[ * ]     Indicates information has been omitted and separately filed with the Securities and Exchange Commission pursuant to an application for an order declaring confidential treatment thereof.

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2.              SALE AND TRANSFER

2.1          Sale and Transfer of the Shares

2.1.1         Object of Purchase

2.1.1.1.     The First Seller holds one Share with a nominal value of EUR [ * ]

2.1.1.2.     The Second Seller holds one Share with a nominal value of  EUR [ * ];

[ * ]          Indicates information has been omitted and separately filed with the Securities and Exchange Commission pursuant to an application for an order declaring confidential treatment thereof.

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2.1.1.3.     The Third Seller holds one Share with a nominal value of EUR [ * ] and one Share with a nominal value of EUR [ * ];

2.1.1.4.     The Fourth Seller holds one Share with a nominal value of EUR [ * ];

2.1.1.5.     The Fifth Seller holds one Share with a nominal value of EUR [ * ] and one Share with a nominal value of EUR [ * ];

2.1.1.6.     The Sixth Seller holds one Share with a nominal value of EUR [ * ] and one Share with a nominal value of EUR [ * ]

in the Company’s share capital totaling EUR 670,000.00. The object of purchase also includes the silent partnership interests listed in clause 2.2.1 of this Agreement.

2.1.2         Consents and Waiver of Pre-emption Rights

In connection with the sale and transfer of the Shares to the Purchaser referred to in clause 2.1.1 of this Agreement, the Sellers, the First Seller and the Second Seller also in their capacity as managing directors of the Company and the Sixth Seller also in his capacity as silent partner according to the agreement dated July 18 th , 2003, each individually irrevocably declare:

2.1.2.1      their consent to the transfer of the Shares and the silent partnership interests to the Purchaser of, to which transfer the shareholders’ meeting has already agreed per shareholders’ resolution attached to this Agreement as Annex E;

2.1.2.2      to waive any potential pre-emption rights, purchase options, accrued interest or similar rights concerning any transferred Shares and interests according to this Agreement.

2.1.3         Sale and Transfer

2.1.3.1  a)                 The First Seller hereby sells to Purchaser his Share with a nominal value of EUR [ * ].  The Purchaser hereby accepts such sale.

b)             The Second Seller hereby sells to Purchaser his Share with a nominal value of EUR [ * ].  The Purchaser hereby accepts such sale.

c)              The Third Seller hereby sells to Purchaser his two Shares with a nominal value of EUR [ * ] and EUR [ * ].  The Purchaser hereby accepts such sale.

d)             The Fourth Seller hereby sells to Purchaser his Share with a nominal value of EUR [ * ].  The Purchaser hereby accepts such sale.

e)              The Fifth Seller hereby sells to Purchaser his two Shares with a nominal value of EUR [ * ]. and EUR [ * ].  The Purchaser hereby accepts such sale.

f)              The Sixth Seller hereby sells to Purchaser his two Shares with a nominal value of EUR [ * ] and EUR [ * ].  The Purchaser hereby accepts such sale.

The sale of the Shares becomes economical effective on the Cut-Off Date.

2.1.3.2      The Sellers hereby transfer their respective Shares, which were sold to Purchaser according to clause 2.1.3.1 lit. a) to f) above. Subject to fulfillment of the condition precedent referred to in clause 2.1.4 of this Agreement, the Purchaser accepts such transfers.

[ * ]          Indicates information has been omitted and separately filed with the Securities and Exchange Commission pursuant to an application for an order declaring confidential treatment thereof.

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2.1.3.3      The sale and transfer also applies to any ancillary rights resulting out of the Shares, including inter alia any dividend rights for the running financial year and any profits of preceding financial years which have not yet been distributed to the shareholders.

2.1.3.4      The Parties hereby authorize the acting notary to notify the Company of the transfer of the Shares according to Sec. 16 para. 1 of the German Act on Companies with Limited Liability ( GmbH-Gesetz ) when the fulfillment of the condition precedent set out in clause 2.1.4 of this Agreement has been announced to the notary .

2.1.4         Condition Precedent

The transfer of the Shares depends on the fulfillment of the condition precedent that all parts of the aggregate price pertaining are paid to each Seller on the accounts set out in clause 3.2 of this Agreement.

2.2.          Sale and Transfer of the Silent Partnership Interests

2.2.1        The First, the Fourth and the Fifth Seller currently hold the silent partnership interests as listed for each Seller in Annex F with an aggregate nominal amount of EUR [ * ] . According to the agreement between the Company and each silent partner attached to this Agreement as Annex G, the agreements concerning the establishment of a silent partnership have been mutually changed to allow the transfer of the silent partnership interests to the Purchaser. The Sixth Seller hereby declares his consent to the transfer of the silent partnership interests of the First, the Fourth and the Fifth Seller to the Purchaser.

2.2.2.        a)             The First Seller hereby sells to Purchaser his silent partnership interest with a nominal amount of EUR [ * ].  The Purchaser hereby accepts such sale.

b)             The Fourth Seller hereby sells to Purchaser his silent partnership interest with a   nominal amount of EUR [ * ].  The Purchaser hereby accepts such sale.

c)              The Fifth Seller hereby sells to Purchaser his silent partnership interest with a nominal        amount of EUR [ * ].  The Purchaser hereby accepts such sale.

The sale of the silent partnership interests becomes economically effective on the Cut-Off Date.

2.2.3        The Sellers referred to in clause 2.2.2 above hereby transfer to Purchaser their silent partnership interests sold pursuant to clause 2.2.2 lit. a) to c) above. Subject to fulfillment of the condition precedent referred to in clause 2.1.4 above, the Purchaser hereby accepts such transfers. The shareholders approved the transfer of the silent partnership interests to the Purchaser in a shareholders’ resolution attached to this Agreement as Annex E .

2.2.4        The sale and transfer also applies to any ancillary rights resulting out of the silent partnership interests, including inter alia any fixed compensation claims, profit participation rights and interests, irrespective of the period to which such rights pertain.

[ * ]          Indicates information has been omitted and separately filed with the Securities and Exchange Commission pursuant to an application for an order declaring confidential treatment thereof.

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3.              PURCHASE PRICE

3.1           Purchase Price

The Purchase Price to be paid to the Sellers as consideration for the Shares listed in clause 2.1 above, for the silent partnership interests listed in clause 2.2 above and for any rights or claims by the Sellers accrued before signing of this Agreement, excluding any claims of the Third and Sixth Seller for which accruals have been included in the financial statement, consists of the Fixed Price and three (3) Earn-Out-Payments, while the Purchase Price may not exceed the aggregate of EUR 8,900,000.00 (in words: Euros Eight million nine hundred thousand). The Fixed Price consists of a cash portion in the amount of EUR 4,072,873.00 and 202,223 registered shares in Bruker BioSciences Corporation (NASDAQ: BRKR), hereinafter also referred to as “ BRKR Shares ”.

3.2           Fixed Price

The Fixed Price shall be split among the Sellers as follows:

a.             The First Seller shall first receive the cash amount of EUR [ * ] as consideration for his silent partnership interest. Further, the First Seller shall receive the cash amount of EUR [ * ] as consideration for his Share. Both amounts are to be paid to his bank account [ * ].

b.            The Second Seller shall receive the cash amount of EUR [ * ] as consideration for his Share, such amount to be paid to his bank account [ * ].

c.              The Third Seller shall receive the cash amount of EUR [ * ] as consideration for his Shares, such amount to be paid to his bank account [ * ].  Further, the Third Seller shall receive [ * ] registered shares in Bruker BioSciences Corporation (NASDAQ: BRKR). According to Annex G, the registered shares are representing the amount of EUR [ * ].

d.             The Fourth Seller shall first receive the cash amount of EUR [ * ] as consideration for his silent partnership interest. Further, the Fourth Seller shall receive the cash amount of EUR [ * ] as consideration for his Share. Both amounts are to be paid to his bank account [ * ].

e.              The Fifth Seller shall receive the cash amount of EUR [ * ] as consideration for his silent partnership. Furter, the Fifth Seller shall receive the cash amount of EUR [ * ] as consideration for his Shares. Both amounts are to be paid to his bank account [ * ].

f.              The Sixth Seller shall receive the cash amount of EUR [ * ] as consideration for his Shares, such amount to be paid to his bank account [ * ].  Further, the Sixth Seller shall receive [ * ] registered shares of Bruker BioSciences Corporation (NASDAQ: BRKR). According to Annex G , the registered shares are representing the amount of EUR [ * ].

3.3           Earn-Out-Payments

In addition to the Fixed Price, the Purchaser will execute in cash three Earn-Out-Payments to the Second, the Third, the Fourth, the Fifth and the Sixth Seller pursuant to the following provisions. The

[ *  ]           Indicates information has been omitted and separately filed with the Securities and Exchange Commission pursuant to an application for an order declaring confidential treatment thereof.

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amount of each Earn-Out-Payment shall be calculated on the basis of the Company’s Revenue during the period relevant for the respective Earn-Out-Payment.

The Earn-Out-Payments shall be split among the Sellers as follows:

a.             the Second Seller shall receive a quota of [ * ] of each Earn-Out-Payment, which is to be paid to the bank account [ * ] ;

b.            the Third Seller shall receive a quota of  [ * ] of each Earn-Out-Payment, which is to be paid to the bank account  [ * ].

c.             the Fourth Seller shall receive a quota of  [ * ] of each Earn-Out-Payment, which is to be paid to the bank account  [ * ];

d.            the Fifth Seller shall receive a quota of [ * ] of each Earn-Out-Payment, which is to be paid to the bank account  [ * ]; *

e.             the Sixth Seller shall receive a quota of [ * ] of each Earn-Out-Payment, which is to be paid to the bank account  [ * ].

The Earn-Out-Payments are conditional upon the respective Seller not being in breach of the non-competition-provision set out in clause 7.1.

3.3.1         Earn-Out-Payment I

The amount of the Earn-Out-Payment I shall be calculated by multiplying the difference between Revenue 06/07 and Revenue 2x H1-06 (i.e. EUR  [ * ] ) with the factor 0.15 (15%) (hereinafter referred to as the “ Valuation Factor ”).

The calculation of the Earn-Out-Payment I can be illustrated as follows by assuming an exemplary Revenue 06/07 of EUR  [ * ].

(Revenue 06/07 - EUR  [ * ] ) x 0.15 = Earn-Out-Payment I

i. e.:          ( [ * ] -  [ * ] ) x 0.15 = EUR [ * ]. *

In the event that the Revenue 06/07 does not reach EUR  [ * ], no Earn-Out-Payment I shall be paid. The Earn-Out-Payment I shall also be cancelled for any Seller in the respective amount if such Seller enters into competition with the Company pursuant to clause 7.1 of this Agreement before pay-out of the Earn-Out-Payment I.

3.3.2         Earn-Out-Payment II

The amount of the Earn-Out-Payment II shall be calculated by multiplying the difference between Revenue 07/08 and Revenue 06/07, such latter amount being not less than EUR [ * ] with the Valuation Factor 0.15 (15%).

If the Revenue 07/08 is less than the Revenue 06/07 or less than the amount of EUR  [ * ] no Earn-Out-Payment II will be paid. The Earn-Out-Payment II shall also be cancelled for any Seller in the respective amount if such Seller enters into competition with the Company pursuant to clause 7.1 of this Agreement before pay-out of the Earn-Out-Payment II.

3.3.3         Earn-Out-Payment III

The amount of the Earn-Out-Payment III shall be calculated by multiplying the difference between Revenue 08/09 and Revenue 07/08, such latter amount being not less than EUR  [ * ], with the Valuation Factor 0.15 (15%).

[ * ]          Indicates information has been omitted and separately filed with the Securities and Exchange Commission pursuant to an application for an order declaring confidential treatment thereof.

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If the Revenue 08/09 is less than the Revenue 07/08 or less than the amount of EUR  [ * ], no Earn-Out-Payment III will be paid. The Earn-Out-Payment III shall also be cancelled for any Seller in the respective amount if such Seller enters into competition with the Company pursuant to clause 7.1 of this Agreement before pay-out of the Earn-Out-Payment III.

3.4           No Repayment of Purchase Price

The Sellers shall not be obliged to repay parts of the Purchase Price by applying the provisions set out in clause 3.3 above.

3.5           Calculation of the Earn-Out-Payments

For the calculation of the Earn-Out-Payments, the following provisions shall apply additionally:

a)             The revenue of a relevant 12-months-period shall be determined by means of a pro forma financial statement to be prepared for such purposes as per June 30 of the respective year, which account is to be prepared according to US-GAAP no later than August 15 of the respective year. The Purchaser and any Seller listed in clause 3.3 above are entitled to attend in person or through their advisors during the preparation of the pro forma financial statement. The Company shall notify the Purchaser and the above mentioned Sellers in writing the Revenue of the respective 12-months-period disclosed in the pro forma financial statement without undue delay after the preparation of the financial statement. Such Revenue shall become binding upon the Parties in the event that neither the above mentioned Sellers nor the Purchaser object to such Revenue in writing while specifying the reasons therefore and naming the resulting new revenue towards the respective other party within 15 Working Days from receipt of the notification of Revenue by the Company.

In case of objection, the following shall apply:

(i)             The respective Revenue is to be established by a certified public accountant to be named by Purchaser and the above mentioned Sellers by mutual consent; or, if the parties are unable to agree on such accountant,

(ii)            the Revenue is to be finally established by a certified public accountant to be appointed upon request by the Purchaser or upon request by the above mentioned Sellers by the public authority named „ Landespräsident Nordrhein-Westfalens der Landesgeschäftsstelle der Wirtschaftsprüferkammer in Düsseldorf ”.

b)            As an arbitrator, the accountant finally decides on the Revenue by applying US-GAAP after hearing the Purchaser and the above mentioned Sellers; the accountant shall only decide upon the issues mentioned in the objection.

c)             The costs of the account