Facile In-Situ Synthesis of Biopolymer Capped Nano Sized Silver Particles: Smartphone Aided Paper-Based Selective Detection of CYS and TC Drugs in Biological and Drug Samples

Herein we are reporting, the in-situ synthesis of polydopamine capped silver nanoparticles (PDA-AgNPs) and its cysteamine (CYS) and tetracycline (TC) drugs sensor applications. The synthesized PDA-AgNPs was characterized by UV-Visible, Fourier Transformed-Infrared, X-Ray Diffraction, Zeta Potential, and High Resolution-Transmission Electron Microscope techniques. We have utilized PDA-AgNPs as probes for the detection of CYS and TC by spectrophotometry method. The addition of CYS has led to a decrease in the absorption of PDA-AgNPs. The yellow color solution becomes colorless and observed the aggregated particles in the TEM image. In contrast, the addition of TC, into the same solution, absorption of PDA-AgNPs was increased. The color of the solution became dark yellow and the particles are obtained de-aggregation. Based on the Surface Plasmon Resonance (SPR) band absorption changes, the detection limit of CYS and TC was calculated to be 180 nM and 17 nM, respectively. Interestingly, 600-fold of common interferences did not interfere with the detection of CYS and TC. PDA-AgNPs was successfully utilized to detect CYS and TC in serum, urine, and drug samples. Finally, we have prepared a paper-based colorimetric kit for on-site monitoring of CYS and TC.

Automated summary

This study presents the in-situ synthesis of polydopamine capped silver nanoparticles (PDA-AgNPs) and their applications as sensors for cysteamine (CYS) and tetracycline (TC) drugs. The PDA-AgNPs were characterized using various techniques, and their detection abilities for CYS and TC were demonstrated through spectrophotometry. The detection limits for CYS and TC were determined to be 180 nM and 17 nM, respectively, with the PDA-AgNPs showing high selectivity and successful detection in serum, urine, and drug samples. Additionally, a paper-based colorimetric kit for on-site monitoring of CYS and TC was developed.