Illicit drug use has a global concern and effective monitoring and interventions are highly required to combat drug abuse. Wastewater-based epidemiology (WBE) is an innovative and cost-effective approach to evaluate community-wide drug use trends, compared to traditional population surveys. Here we report for the first time, a novel quantitative community sewage sensor (namely DNA-directed immo...

An ultrasensitive DNA biosensor has been developed through in-situ labeling of electroactive melamine-Cu(2+) complex (Mel-Cu(2+)) on the end of hairpin-like probe using gold nanoparticles (AuNPs) as the signal amplification platform. The 3'-thiolated hairpin-like probe was first immobilized to the gold electrode surface by the Au-S bond. The AuNPs were then tethered on the free 5'-end of the im...

Targeting drug delivery to hair follicles is valuable treat conditions such as alopecia’s and acne, this shunt route may also allow deeper skin layers the systemic circulation by avoiding intact stratum corneum. Here, we investigated effects of nanoparticle surface chemistry on their into synthesizing fluorescent thiolated silica nanoparticles functionalizing with 750 Da 5000 methoxypolyethylen...

We incorporated short thiolated oligonucleotides as passivating diluents in the fabrication of electrochemical peptide-based (E-PB) sensors, with the goal of creating a negatively charged layer capable of resisting non-specific adsorption of matrix contaminants. The E-PB HIV sensors fabricated using these diluents were found to be more specific and selective, while retaining attributes similar ...

a r t i c l e i n f o Keywords: Gapped-duplex DNA-mediated electron transfer Label-free Cryptosporidium parvum Electrochemical impedance spectroscopy A label-free platform for DNA mismatch detection, that has the potential to overcome the major drawbacks of conventional microarrays, is proposed. We have designed a gapped-duplex-based approach for achieving horizontally aligned probe-DNA on a so...

A conducting atomic force microscope was used to measure the electrical properties of carotenoid molecules attached to a gold electrode. The thiolated carotene molecules were embedded in insulating n-alkanethiol self-assembled monolayers. At a contact force of a few nanoNewtons, a carotenoid molecule behaves ohmically with a resistance of approximately 4.2 ( 0.7 GΩ, over a million times more co...