Colorimetric chiral recognition of d/l-phenylalanine based on triangular silver nanoplates

Abstract

A new colorimetric analysis approach for chiral recognition of D- and L-forms of phenylalanine (phe) was developed based on triangular silver nanoplates (TAg-NPs). The TAg-NPs could be used as chiral colorimetric probes for D- and L-forms of phe. Upon addition of D-phe to TAg-NPs solution, a color change from blue to purple to pink could be observed, while no obvious color change was found on addition of L-phe. L-phe could prevent the TAg-NPs from being etched to small size particles while the protective effect of D-phe was weak. Moreover, the enantiomeric excess of D-phe could be determined using the proposed chiral assay in the percentage of L-phe from 0 to 100% with a correlation coefficient of 0.9855. The phenomenon could be monitored by bare eyes and quantified analysis by UV-Vis spectrophotometry. The developed approach had several advantages, such as simplicity, visualization, short analysis time and low cost. This study presented a fast visualization analysis method of chiral D/L-phenylalanine and may lay the foundation for the development of visualization chiral recognition of other target analytes.

Tuning of hydrogen peroxide etching during the synthesis of silver nanoparticles. An application of triangular nanoplates as plasmon sensors for Hg2+ in aqueous solution

“…Therefore, based on the SEM results, when 0.5 mg l −1 of Hg 2+ is added, additional etching of the triangular nanoplates is obtained along with the formation of hexagonal and pentagonal nanoplates due to the erosion effect [33,54,55].…”