Colorimetric determination of cysteamine based on the aggregation of polyvinylpyrrolidone-stabilized silver nanoparticles

Extending Ag Nanoparticles as Colorimetric Sensor to Industrial Zinc Electrolyte for Cobalt Ion Detection

“…Additionally, adsorption of Zn 2+ takes place after the addition of 50 g/L Zn 2+ , as revealed by the similar increase of zeta potential from −9.91 mV to 0.19 mV. Importantly, introducing 2 mg/L Co 2+ into the 50 g/L Zn 2+ solution induces the further increase of zeta potential from 0.19 mV to 0.3 mV, demonstrating that the adsorption of Co 2+ in the high-concentration Zn 2+ solution (50 g/L) can still proceed smoothly [ 32 ].…”

“…For single PVP-AgNPs, a strong absorption peak at around 393 nm is observed ( Figure 1 b), implying the highly dispersed state of the particles [ 30 , 31 ]. After adding Co 2+ , the peak intensity at 393 nm progressively decays with the increase of Co 2+ concentration, accompanied by the intensity enhancement of a newly generated peak at 533 nm ( Figure 1 b), which denotes the distance decrease between particles in the solution [ 32 ]. The above phenomenon means that adding Co 2+ induces the aggregation of PVP-AgNPs in the solution, implying that the trace Co 2+ is grabbed by the PVP chains on the surface of AgNPs [ 29 ].…”

Use of metal nanoparticles for preconcentration and analysis of biological thiols

“…A lower LOD (46 nM) with the alternative method based on the same principle was achieved by using AgNPs capped with thiomalic acid [110]. Yet another possibility for the CA colorimetric determination with even lower LOD (4.9 nM) was the polyvinylpyrrolidone‐stabilized AgNPs [111]. In this work, the color of the solution changes from pale yellow to purple.…”

Recent progress in 0D optical nanoprobes for applications in the sensing of (bio)analytes with the prospect of global health monitoring and detailed mechanistic insights

“…176,200 Ilanchelian et al reported the preparation of a simple, chromogenic polyvinylpyrrolidone-stabilized AgNP-based nanosensor for the selective detection of cysteamine. 201 The corresponding chromogenic change from pale yellow to purple was observed via the cysteamine-induced aggregation of the NPs, leading to a decrease followed by bathochromic shift in the SPR band from 395 nm to 436 nm with a shoulder peak at 436 nm, which may be due to the strong electrostatic interaction of the positively charged cysteamine with the negatively charged PVP-AgNPs. The sensing sensitivity towards cysteamine was also investigated in real human blood serum samples, where cysteamine was recovered at a high rate (96–101.8%), demonstrating the practical applicability of the developed nanosensor (Fig.…”