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Abstract: We report on microsensor for direct detection of microorganisms in aerosol. Microsensor is based on interdigitated ultramicroelectrodes modified with electropolymerized 3‐aminophenylboronic acid (3‐APBA). Appearance of Penicillium chrysogenum in aerosol as well as further increase of its concentration lead to poly(3‐APBA) conductivity increase found by impedance spectroscopy. According to Raman spectroscopy data, the presence of microorganism affects polymer conductivity similarly to binding of glucose to polymer which results in self‐doping phenomenon. The elaborated detection technique is 100 times faster comparing to agar plate cultivation: it requires less than 20 minutes for analysis. Dynamic range of microsensor includes the upper limit for non‐contaminated air in Russian hygienic standard (500 colony‐forming units per cubic meter). The first reported reagentless detection of Penicillium chrysogenum in aerosol by conductivity increase reveals a prospect for creation of a promising alternative to conventional techniques for detection of microorganisms. [ABSTRACT FROM AUTHOR]

Abstract: We report on Prussian Blue based (bio)sensors displaying advantageous analytical performance characteristics when operated both in conventional three‐electrode regime powered by potentiostat and in power generation mode. ‘Self‐powered’ sensors are commonly aimed to produce sufficient energy for signalling and, thus, being energetically autonomous. In order to generate maximum energy output, the electrodes with high potential difference are preferable. In contrast, we propose the systems with the lowest potential difference between the working and the counter electrodes. Short‐circuiting the Prussian Blue modified working and the Ag|AgCl reference electrode, working electrode potential is adjusted to 0.00 V without potentiostat. The efficiency of the (bio)sensors in power generation mode is achieved due to high catalytic activity of Prussian Blue at 0.00 V versus Ag|AgCl reference. Here we discuss the benefits of the Prussian Blue based (bio)sensors operated through power generation in a short‐circuit regime without potentiostat, including an order of magnitude decreased noise and simplified readout. The multimodality of the sensors would provide their versatile functionality for the electroanalysis and elaboration of miniature highly sensitive wearable devices. [ABSTRACT FROM AUTHOR]