[Surface-Enhanced Raman Scattering to Improve the Sensitivity of the MTT Assay].

Currently, empirical therapy regimens are often used in the treatment of infectious diseases that are not based on data on pathogen resistance. One of the main reasons for the unjustified prescription of antibacterial drugs is the lack of rapid and at the same time universal methods of determining the antibiotic resistance of the pathogen. The most widely used culture techniques, such as the microdilution method, require a long time to generate the necessary number of bacterial cells.

Cytosine mimic azophenoxazine tC quenches FAM fluorescence and provides concentration-dependent Raman quenching upon molecular beacon hybridization.

The molecular beacon (MB) strategy finds diverse applications in bioimaging, biosensing and disorders diagnostics. Classic MBs are stem-loop oligonucleotides modified with a reporter and a quencher at the 5'- and 3'- ends. Hybridization with a specific target leads to spatial separation of the quencher and the reporter with subsequent changes in spectral signal, for example, an increase in reporter fluorescence emission.

Aptamer-coated track-etched membranes with a nanostructured silver layer for single virus detection in biological fluids.

Aptasensors based on surface-enhanced Raman spectroscopy (SERS) are of high interest due to the superior specificity and low limit of detection. It is possible to produce stable and cheap SERS-active substrates and portable equipment meeting the requirements of point-of-care devices. Here we combine the membrane filtration and SERS-active substrate in the one pot.

Model of the SARS-CoV-2 Virus for Development of a DNA-Modified, Surface-Enhanced Raman Spectroscopy Sensor with a Novel Hybrid Plasmonic Platform in Sandwich Mode.

The recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has posed a great challenge for the development of ultra-fast methods for virus identification based on sensor principles. We created a structure modeling surface and size of the SARS-CoV-2 virus and used it in comparison with the standard antigen SARS-CoV-2-the receptor-binding domain (RBD) of the S-protein of the envelope of the SARS-CoV-2 virus from the Wuhan strain-for the development of detection of coronaviruses using a DNA-modified, surface-enhanced Raman scattering (SERS)-based aptasensor in sandwich mode: a primary aptamer attached to the plasmonic surface-RBD-covered Ag nanoparticle-the Cy3-labeled secondary aptamer. Fabricated novel hybrid plasmonic structures based on "Ag mirror-SiO-nanostructured Ag" demonstrate sensitivity for the detection of investigated analytes due to the combination of localized surface plasmons in nanostructured silver surface and the gap surface plasmons in a thin dielectric layer of SiO between silver layers.