Sensitive Colorimetric and Fluorimetric Probe for the Detection of Sodiumvalproate using Gulutathione Capped Silver Nanoclusters

Silver nanoclusters were synthesized and passivated by glutathione (GSH) ligand, with high aqueous stabipowerful red fluorescence and UV-Vis light yellow colour. A novel colorimetric and fluorimetric assays have been presented for the detection of sodium valproate using glutathione capped silver nanoclusters, (GSH-Ag NCs) as a colorimetric and fluorimetric sensor. The size of the AgNCs-GSH was found to be ~ 10 nm on DLS. The fluorimetric detection of GSH-AgNCs with sodium valproate exhibited excitation bands 600 nm and 360nm respectively and sodium valproate emission indicated showed 3 emission bands within near visible region emission observed at (472, 700 and 760nm) and their relative intensities were2.863, 0.310 and 27.483 respectively. The detection of sodium valproate was accomplished by observing color change of GSH-AgNCs solution from light yellow to brown due to aggregation induced by sodium valproate. GSH-Ag NCs absorbed maximally at 370 nm and after the addition of the drug sodium valproate, the band shifted to 600 nm. The aggregation of GSH-Ag NCs was characterized by UV–Vis spectrometry and fluorimtery, scanning electron microscopy (SEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), and zeta potential. Under optimized Conditions, linear calibration curve was obtained within concentration range of 1–8 μg/ml with detection limits of 0.4 μg/ml and limit of quantitation 1.23 μg/ml, respectively. The Fluorescence calibration range was 1-5 µg/ml with limit of detection (LOD) 0.06 μg/ml and limit of quantitation (LOQ) 0.202 µg/ml respectively, showing proposed method to be sensitive. Furthermore, the developed colorimetric assay was found to be simple, sensitive, reproducible and a number of pharmaceutical additives did not affect the determination u a Colorimetric and fluorimetric platform, Sodium valproate was analysed in pharmaceutical formulation, and biological fluids including spiked human urine and blood serum samples with % recoveries of 99.2%and 99.3%.

Asma Laghari and Muhammad Yar Khuhawar