Candida parapsilosis ATCC 7330 supported gold nanoparticles (CpGNP), prepared by a simple and green method can selectively reduce nitroarenes and substituted nitroarenes with different functional groups like halides (–F, –Cl, –Br), olefins, esters and nitriles using sodium borohydride. The product aryl amines which are useful for the preparation of pharmaceuticals, polymers and agrochemicals were obtained in good yields (up to >95%) using CpGNP catalyst under mild conditions. The catalyst showed high recyclability (≥10 cycles) and is a robust free flowing powder, stored and used after eight months without any loss in catalytic activity.
The article reports a proof of concept validation of bacterial detection using Siderophores. Desferrioxamine B (DesfB) was used as the Siderophore to capture Escherichia coli on gold coated microcantilever surface. Self-assembled monolayer based gold thiol chemistry was used for surface functionalization of the Siderophore on top surface of the microcantilever. The bacterial attachment to the siderophore was observed through Fourier Transform Infrared Spectroscopy (FTIR) and Fluorescence Microscopy. The DesfB coated surface allows only the live bacterial cells to be attached and it is evident through the FTIR band formation. In a mixture of live and dead E. coli cells, the Fluorescence Microscope image indicates green emission from live cells and a core-shell structure formation upon progress of time. For a sample dilution of 10−1, the mass change of live E. coli bonded to Siderophores is four times higher than that of dead cells and 12 times higher to that of negative control on microcantilevers. Therefore this study should be considered as a foundation to build a miniaturized biosensing platform to distinguish between bacterial or viral infections in real time. The proposed platform could differentiate between bacterial and viral infections thus rendering it as Point of Care (PoC) diagnostic tool aiding Internet of Things (IoT) applications.