In the fight against drug-resistant bacteria, accurate and high-throughput detection is essential. Here, a bimaterial microcantilever with an embedded microfluidic channel with internal surfaces chemically or physically functionalized with receptors selectively captures the bacteria passing through the channel. Bacterial adsorption inside the cantilever results in changes in the resonance frequency (mass) and cantilever deflection (adsorption stress). The excitation of trapped bacteria using infrared radiation (IR) causes the cantilever to deflect in proportion to the infrared absorption of the bacteria, providing a nanomechanical infrared spectrum for selective identification. We demonstrate the in situ detection and discrimination of Listeria monocytogenes at a concentration of single cell per μl. Trapped Escherichia coli in the microchannel shows a distinct nanomechanical response when exposed to antibiotics. This approach, which combines enrichment with three different modes of detection, can serve as a platform for the development of a portable, high-throughput device for use in the real-time detection of bacteria and their response to antibiotics.

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Measurement of femtoscale displacements in the ultrasonic frequency range is attractive for advanced material characterization and sensing, yet major challenges remain in their reliable transduction using non-optical modalities, which can dramatically reduce the size and complexity of the transducer assembly. Here we demonstrate femtoscale displacement transduction using an AlGaN/GaN heterojunction field effect transistor-integrated GaN microcantilever that utilizes piezoelectric polarization-induced changes in two-dimensional electron gas to transduce displacement with very high sensitivity. The piezotransistor demonstrated an ultra-high gauge factor of 8,700 while consuming an extremely low power of 1.36 nW, and transduced external excitation with a superior noise-limited resolution of 12.43 fm Hz−1/2 and an outstanding responsivity of 170 nV fm−1, which is comparable to the optical transduction limits. These extraordinary characteristics, which enabled unique detection of nanogram quantity of analytes using photoacoustic spectroscopy, can be readily exploited in realizing a multitude of novel sensing paradigms.

Recently, a new and fatal strain of coronavirus named as SARS-CoV-2 (Disease: COVID-19) appeared in Wuhan, China in December of 2019. Due to its fast growing human to human transmission and confirmed cases in nearly every country, it has been declared as pandemic by World Health Organisation (WHO) on 11 March 2020. Till now, there is no therapy such as vaccines and specific therapeutic agents available globally. Inspite of this, some protease inhibitors and antiviral agents namely lopinavir, ritonavir, remdisivir and chloroquine are under investigation and also implemented in several countries as therapeutic agents for the treatment of COVID-19. Seeing the health crisis across the world, it was our aim to find out a suitable drug candidate which could target SARS-CoV-2.For this purpose, molecular docking of 7 proteinsof SARS-CoV-2 was done with 18active constituents that have previously been reported to be antiviral or anti-SARS-CoV agents. The docking results of these 18 compounds were compared with 2 FDA approved drugs that have are currently being used in COVID 19, namely Remdesivir and Chloroquine. Our result revealed that among all, epigallocatechin gallate (EGCG), a major constituent of green tea, is the lead compound that could fit well into the binding sites of docked proteins of SARS-CoV-2. EGCG showed very strong molecular interactions with binding energies -9. 30, -8.66, -8.38, -7.57, -7.26, -6.99 and -4.90 kcal/mole for6y2e, 6vw1, 6vww, 6lxt,6vsb, 6lu7 and 6lvnproteins of SARS-CoV-2, respectively.Therefore, EGCG as per our results, should be explored as a drug candidate for the treatment of COVID-19.