Chromatography system based on amorphous silicon sensor

In this work, we present a ‘smart thin layer chromatography plate’: a system which couples a linear array of amorphous silicon p–i–n photodiodes with a TLC plate. The basic idea is to monitor in real-time the separation of the components of the mixture during the chromatographic run. These are achieved by measuring the natural fluorescence/absorption of the compounds induced by UV radiation. The ‘smart TLC plate’ has been tested on several mixtures of naturally fluorescent molecules proving the suitability of our system to provide qualitative and quantitative information on their composition. In particular, quantification performance has been verified comparing the intensity of the sensor photocurrent measured at different quantities of fluorescein spotted on the TLC plate. An excellent linearity has been achieved.