Integrated flow-through optical biosensors

The monitored species was the 4-nitrophenol formed in the reaction, which exhibited maximal absorbance at 405 nm. 

The comparative study was based on several criteria including the features of the FI approach used and those of the methods developed by using the same biosensor but a different measurement parameter, or by using the same parameter and different FI biosensors. 

The complexity of die flow injection manifold required by the three approaches was very similar. All of them necessitated electronic interfaces to control the propulsion and injection systems through the microcomputer in approaches I and II, and the injection and switching valves in manifold III. A passive electronic interface was also required in all three manifolds in order to acquire data fi om the biosensor/detection system. 

The sensitivity of the biosensor based on iterative reversal of the flow direction could be trebled by using the fourth rather than the second peak, to the detriment of sample throughput. The repeatability of the three approaches was excellent (the RSD was less than 2% in every case) [53], 

Bioluminescent reactions have been thoroughly investigated with a view to designing integrated flow-through biosensors using firefly and bacterial 

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