Publications by authors named "Varduhi A Hovhannisyan"
Urease combined with CdSe quantum dots as an enzyme sensor for quantitative detection of some metals in water.
Spectrochim Acta A Mol Biomol Spectrosc
February 2025
Article Synopsis
- The study explores how urease can be used as an enzymatic sensor alongside CdSe quantum dots (QDs) to detect various metals in water.
- Urease breaks down urea, producing ammonia which raises the pH and boosts the fluorescence of QDs; however, metals can inhibit this process, impacting fluorescence.
- The method identifies metals like Cu, Co, Mg, Fe, Cr, Zn, and Ni with a sensitivity of 0.2 μM, making it useful for assessing water quality for food safety.
Anisotropic silver nanoparticles sensitized by various lectins were applied for detection of yeast (Saccharomyces cerevisiae) which was used as a model of fungal cells. It was shown that high concentrations of yeast cells have stabilized silver nanoparticles, preventing their aggregation in the presence of NaCl whereas at low concentrations of cells, the salt has induced aggregation of nanoparticles with drastic changes in optical spectra. These changes depend on cell concentration and permit the detection of cells in the range from 3.
View Article and Find Full Text PDFC-type lectin from hen egg shell as a recognition ligand for detection of St. aureus was applied. Three approaches for detection of bacteria were used and the sensitivities of the assays were compared.
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