SERS-based biosensor with Raman-active external responsive element for rapid determination of adenosine monophosphate

A Combination of Membrane Filtration and Raman-Active DNA Ligand Greatly Enhances Sensitivity of SERS-Based Aptasensors for Influenza A Virus

“…Recently, we have found that the BHQ-2 amine and the BHQ-2 guanidine provide strong SERS signals compared to classic BHQ-2. The positive charge of the dye was supposed to play the key role in the enhancement of Raman spectra due to adsorption on the surface of negatively charged nanoparticles ( Zavyalova et al, 2022 ). In this work, the BHQ-2 amine was shown to provide SERS spectra even in undiluted biological fluids ( Figure 6 ), whereas other soluble dyes (cyanine 3, Bodipy FL, rhodamine 6G, BHQ-2, and cyanine 5) were not detected under these conditions.…”

“…SERS-based techniques provide high sensitivity with a short time of analysis. We aimed to minimize the time of analysis to 15 min in this work and our previous works ( Kukushkin et al, 2019 ; Gribanev et al, 2021 ; Gribanyov et al, 2021 ; Zavyalova et al, 2022 ; Zhdanov et al, 2022 ), which places the techniques in the raw of rapid point-of-care tests. SERS equipment is of rather high cost; here, we used a portable device with the price 15,000 USD with a user-friendly interface (RaPort instrument from Enhanced Spectrometry, United States).…”

“…The synthesis of the BHQ-2 amine dye was performed according to the literature ( Zavyalova et al, 2022 ); for the BHQ-2 amine structure Supplementary Figure S7 can be referred. The compound is a derivative of Black Hole Quencher-2 (BHQ-2) with two additional amino groups.…”

“…3.3 Affinity of BHQ-2 Amine to the DNA Aptamer and Its Raman Spectra on the SERS-Active Surface BHQ-2 amine has been developed recently as a Raman-active dye with affinity to non-canonical DNA structures (Zavyalova et al, 2022). It has been shown to bind guanine stacked between G-G and G-A pairs in aptamers for adenosine monophosphate.…”

Lithographic SERS Aptasensor for Ultrasensitive Detection of SARS-CoV-2 in Biological Fluids

“…Recently, aptamer-based analysis methods have been actively developed due to their low cost, high stability, ease of modification, and superior specificity and affinity. Combining the surface enhancement of Raman scattering and luminescence with molecular recognition through aptamers has a promising future as it allows to create effective and inexpensive sensor designs for detecting molecular targets of various nature, such as low-molecular-weight compounds [ 23 ], protein toxins [ 24 ], bacteria [ 25 ], viruses [ 12 , 26 ], and circulating cancer cells [ 27 , 28 ].…”