Explosives are powerful destructive weapons used by criminals and terrorists across the globe and their use within military installation sites poses serious environmental health problems. Existing colorimetric sensors for triacetone triperoxide (TATP) relies on detecting its hydrolysed HO form. However, such detection strategy limits the practicability for on-site TATP sensing.
View Article and Find Full Text PDFJ Phys Condens Matter
October 2021
We present studies of the formation of silver nanoparticles (NPs) in silver-sodium ion-exchanged glasses by a combination of thermal poling and nanosecond pulsed laser irradiation at 355 nm. In poling, silver ions drift deeper into the glass and become separated from the glass surface by a poled layer depleted in cations. Performed measurements have indicated poling-induced broadening of silver ions depth distribution.
View Article and Find Full Text PDFThe International Agency for Research cancer (IARC) has classified nitrite in Group 2A of probable carcinogens to human. Herein, we report on the rapid and selective colorimetric detection of nitrite using a chemically modified gold nanoparticle (AuNP)-cerium oxide (CeO) NP-anchored graphene oxide (GO) hybrid nanozyme in a catalytic colorimetric assay where nitrite acts as the main oxidant/target analyte and 3,3',5,5'-tetramethylbenzidine (TMB) as the substrate. CeO NPs and GO were synthesized separately and incorporated in-situ, in a synthetic solution involving the chemical reduction of Au salt to AuNPs.
View Article and Find Full Text PDFAmphetamine-type stimulants are a class of illicit drug that constitutes a worldwide problem to which intelligence agencies, first responders and law enforcement are tasked with identifying them in unknown samples. We report on the development of a graphene oxide (GO)-cationic multi-shaped gold nanoparticle (AuNP)-hemin hybrid nanozyme as a new biomimetic catalytic-induced aptamer-based colorimetric biosensor platform for amphetamine (AMP) and methamphetamine (MAMP). GO was electrostatically bonded to cationic multi-shaped cetyltrimethylammonium bromide (CTAB)-AuNPs to form a GO-CTAB-AuNP hybrid nanozyme exhibiting enhanced catalytic activity in the presence of hemin.
View Article and Find Full Text PDFAuthors report on a new fluoro-graphene-plasmonic nanohybrid aptamer-based fluorescent nanoprobe for cocaine. To construct the nanoprobe, newly synthesized glutathione-capped ZnS/AgSe quantum dots (QDs) were first conjugated to graphene oxide (GO) to form a QD-GO nanocomposite. The binding interaction resulted in a fluorescence turn-ON.
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