Application of silver nanoparticles decorated with β-cyclodextrin in determination of 6-mercaptopurine by surface-enhanced Raman spectroscopy

Abstract

Although classical silver nanospheres were widely used as the probes in surface-enhanced Raman spectroscopy (SERS), they lacked long-term stability. In the present work, the silver nanoparticles decorated with β-cyclodextrin (β-CD-AgNPs) were used as the probe and the stability was improved. The adsorption characteristics of 6-mercaptopurine (6-MP) on classical silver nanospheres and β-CD-AgNPs were studied cautiously using SERS, and chemical information of the molecular structure was obtained. The binding of 6-MP molecule to the surface of AgNPs is based on the stable Ag-S covalent bond. The electrostatic adsorption between protonated N 7 atom or N 1 atom and the silver surface results in a notable Raman enhancement. The intensity of the Raman band of 6-MP at 866 cm −1 was used to determine 6-MP. The experimental conditions, such as volume of CD-AgNPs solution, incubation time, pH value and concentration of sodium chloride were examined and optimized.Compared with classical silver nanospheres when β-CD-Ag nanoparticles were used, the sensitivity was higher, the analytical time was shorter, and the linear range was wider. A good linearity (r=0.996) in the range of (0.040-2.0) ×10 -7 mol·L -1 was obtained for determining 6-MP. The limit of detection is 0.024×10 -7 mol·L -1 and the limit of quantification is 0.080×10 -7 mol·L -1 . This method was successfully applied to the determination of 6-MP in real samples and the results were satisfactory.

Superabsorbing Metasurfaces with Hybrid Ag–Au Nanostructures for Surface‐Enhanced Raman Spectroscopy Sensing of Drugs and Chemicals

“…As shown in Figure e, the degradation rate of the peak intensity at 1608 cm −1 is less than 10%, which is much better than previously reported nanostructures (see data captured from refs. in Figure e). This comparison demonstrated that the proposed Ag–Au metasurface stayed effective after one year shelf time in an ambient storage environment.…”

“…e) Direct comparison of Raman intensities over different periods obtained by previously reported structures (data from refs. ) and the metasurface (i.e., the red stars).…”

Potential of Surface Enhanced Raman Spectroscopy (SERS) in Therapeutic Drug Monitoring (TDM). A Critical Review

“…Another possible approach is to modify the nanoparticles with molecules that can mediate the interaction with the analyte. Yang et al [ 75 ] have shown that silver nanoparticles coated with β-cyclodextrin (β-CD) are more efficient as SERS substrates when compared to the citrate-reduced colloids. The authors of this study showed that the addition of β-CD improves sensitivity, time of analysis, and the linear range of the SERS response, besides making the colloids more stable toward aging.…”

Synthesis and Comparative Biological Properties of Ag-PEG Nanoparticles with Tunable Morphologies from Janus to Multi-Core Shell Structure

“…Silver nanoparticles (AgNPs) have attracted increasing interest due to their unique physical, chemical and biological properties, including surface-enhanced Raman scattering, catalytic activity, non-linear optical behavior and broad-spectrum bactericidal activity [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. Many methods have been reported for the synthesis of AgNPs with chemical, physical, photochemical and biological routes with tunable size and shape [ 10 , 11 , 12 , 13 , 14 , 15 ].…”