Clay nanosheets simultaneously intercalated and stabilized by PEGylated chitosan as drug delivery vehicles for cancer chemotherapy.

Montmorillonite (MMT) has been frequently utilized as drug vehicles due to its high specific surface area, excellent cation exchange capacity and biocompatibility. However, the significant flocculation of MMT under physiological condition restricted its application to drug delivery. To conquer this problem, the graft-type PEGylated chitosan (PEG-CS) adducts were synthesized as intercalator to stabilize MMT dispersion.

Methylene blue-mediated photodynamic inactivation as a novel disinfectant of enterovirus 71.

Objectives: We tested whether methylene blue, an inexpensive and safe photosensitizer, is feasible for photodynamic inactivation of enterovirus 71 (EV71) in the environment.

Methods: By escalating light doses and photosensitizer concentrations, photoinactivation of EV71 and other enteroviruses was examined in vitro. Viral transmission in the environment was simulated with a neonatal mouse model in vivo.

Ultra-sensitive detection of mutated papillary thyroid carcinoma DNA using square wave stripping voltammetry method and amplified gold nanoparticle biomarkers.

This study presents an ultra-sensitive technique for the electrochemical detection of the mutated BRAF gene associated with papillary thyroid carcinomas (PTC). In the proposed approach, a biotinylated 30-nucleotides probe DNA was immobilized in a streptavidin-modified 96-well microtiter plate and the free active sites of the streptavidin were blocked using biotinylated bovine serum albumin (BSA). The biotinylated target DNA was then added and allowed to hybridize with the immobilized probe DNA for 30min.

Poly(methyl methacrylate) microchip device integrated with gold nanoelectrode ensemble for in-column biochemical reaction and electrochemical detection.

This paper proposes a poly(methyl methacrylate) (PMMA) based microchip with an integrated gold nanoelectrode ensemble (GNEE) and a quartet-T loading channel for in-column urea/urease reactions and electrochemical detections. The on-chip GNEE electrode is fabricated using an electrodeless deposition process on a thin polycarbonate (PC) film and bonded directly onto a PMMA substrate to carry out high-performance electrochemical detections. The in-column bio-catalytic reaction of urea/urease is successfully demonstrated utilizing a novel approach based on the different electrokinetic mobilities of urea and urease in capillary electrophoresis (CE) channel.

Digital pulse ac voltammetry for the simultaneous analysis of electroactive and electrosorptive species in flow systems.

A digital two-step and three-step pulse potential ac voltammetry system was proposed and applied for the simultaneous analysis of electrosorptive and electroactive species in flow systems. To perform the ac polarography function, a PC was interfaced to a potentiostat to mimic all the necessary hardware functions of an analog ac polarograph. From the measurement of the change of phase-selective charging current and the zero-order current, I(3)(-), Br(-) specifically adsorbed and Cd(2+), Pb(2+) reduced at a hanging mercury drop electrode can be determined simultaneously in a FIA and IC system.

Immunoassay with a microtiter plate incorporated multichannel electrochemical detection system.

To extend the application of a multichannel electrochemical detector (MED) for immunoassay, a MED system consisting of 8 sets of Pt electrodes in an arrangement fitted with the dimensions of a row of microtiter wells in a microtiter plate and a microcomputer-assisted 16-channel potentiostat was constructed. With this developed MED system, electroactive enzymatic products produced in eight microtiter wells can be analyzed simultaneously with a developed amperometric procedure. To demonstrate the applicability of the MED system for immunoassay, an immunosystem containing rabbit-IgG and alkaline phosphatase-conjugated goat anti rabbit-IgG was studied.