Sensors indigo

The aim of an indigo sensor is to keep the leuco-indigo concentration in the solution at a constant value. In the past, different methods were developed for detection of the indigo and sodium dithionite concentration, but up to now with limited success. The sodium dithionite concentration can be determined by volumetric titration with iodine2 22 or with K3[Fe(CN)6]23. The endpoint detection of these titrations can be done visually22,24"25 or... 

The novel water-soluble dye 64 shows sufficient stability for potential application in molecular-based beacons for cancer detection using optical imaging <2005BCC735>. An optochemical ozone sensor with a quantitation limit of 0.03 ppm and accuracy exceeding 8% has been obtained by immobilization of the novel soluble indigo derivative 65 in permeable transparent polymeric films of polydimethylsiloxane-polycarbonate <2005MI1628>. 

Once the procedure was optimized, an enzymatic genosensor for the identification of a nucleic acid determinant exclusively present on the genome of the pathogen S. pneumoniae was developed. This DNA sensor has been described and optimized by our research group in the previous section. In this work, for the electrochemical detection step, 3-IP was used as substrate and then sulfuric acid was added to generate an electroactive compound termed indigo carmine, which is quantified by cyclic voltammetry. 

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