Assessing Stability of Gold Nanoparticles in Presence of Two Enzymes, RNaseA and RNaseH, Using Colorimetric Detection

Gold nanoparticle-based diagnostic methods have attracted much attention due to their simplicity, high sensitivity and low cost. These methods are mostly used for early and efficient detection of various pathogenic factors and assessment of gene expression and nanoparticles stability. In this study, melon plants were cultured in vivo and then, RNA was extracted from leaf explants. A 40 bp probe was designed based on the Actin gene sequence and applied to investigate the gene expression by colorimetric detection. Color variation of the nanoparticles, from red to blue was observed in presence of the target molecules. The maximum observed changes was at 550-650 nm. Moreover, the activity and the effect of two enzymes, RNaseA and RNaseH, on the stability of gold nanoparticles were investigated. The results showed the effect of the RNaseA enzyme in the initial time period along with the RNaseH enzyme over the time on the stability of gold nanoparticles. Such colorimetric techniques, which are based on the stability of the gold nanoparticles could be used for rapid assessment and recognition of gene expression and the factors affecting the stability of the gold nanoparticles. These could also be considered as a useful technique for screening other enzymes and medicinal molecules.