Novel integrated electrochemical nano-biochip for toxicity detection in water
ABSTRACT An electrochemical nano-biochip for water toxicity detection is presented. We describe chip design, fabrication, and performance. Bacteria, which have been genetically engineered to respond to environmental stress, act as a sensor element and trigger a sequence of processes, which leads to generation of electrical current. This novel, portable and miniature device provides rapid and sensitive real-time electrochemical detection of acute toxicity in water. A clear signal is produced within less than 10 min of exposure to various concentrations of toxicants, or to stress conditions, with a direct correlation between the toxicant concentration and the induced current.
SourceAvailable from: Jian Chen[Show abstract] [Hide abstract]
ABSTRACT: Arsenic is a natural environmental contaminant to which humans are routinely exposed and is strongly associated with human health problems, including cancer, cardiovascular and neurological diseases. To date, a number of biosensors for the detection of arsenic involving the coupling of biological engineering and electrochemical techniques has been developed. The properties of whole-cell bacterial or cell-free biosensors are summarized in the present review with emphasis on their sensitivity and selectivity. Their limitations and future challenges are highlighted.11/2014; 4(4):494-512. DOI:10.3390/bios4040494
[Show abstract] [Hide abstract]
ABSTRACT: A new and simple strategy based on nanostructured CaCO3-poly(ethyleneimine) (PEI) microparticles (MPs) for phenol sensing using PDMS/glass fluidic microchip is developed. This fluidic microsystem including integrated screen-printed electrodes modified with CaCO3-PEI MPs and tyrosinase (Tyr) through cross-linking with glutaraldehyde, represents a low-cost platform for phenol detection. The designed fluidic microsystem improves the sensitivity of the biosensor allowing the detection of very low concentrations of phenol (up to 10 nM). This device shows high repeatability and low detection limit, is easy to be fabricated, inexpensive, disposable, and amenable to mass production.Electrophoresis 07/2013; 34(14). DOI:10.1002/elps.201300056 · 3.16 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Metal coordinating C2-symmetric phenolic chelating ligands (1-3) were used to prepare surface functionalized AgNPs for selective colorimetric sensing of metal cations and anions. The effect of subtle structural and conformational change of 1-3 on the colorimetric sensing was also explored. UV-Visible, IR spectroscopy and HR-TEM techniques were used to characterize AgNPs. Interestingly 1-, 2- and 3-AgNPs showed different colorimetric sensing of metal cations and anions. Aliphatic flexible diamine based 1-AgNPs showed selective sensing of Co2+ ions (10-7 M), oxalate and dihydrogen phosphate anions (10-6 M). Co2+ addition to 1-AgNPs produced brownish-orange colour whereas oxalate and phosphate resulted in brownish-pink colour due to aggregation. Alicyclic diamine based 2-AgNPs exhibited selective precipitate formation for Pb2+ ions without showing any anion sensing. The rigid diamine based 3-AgNPs showed selective decolourisation of yellow colour for Hg2+ and nitrite anions due to amalgamation and oxidation. Thus phenolic chelating ligands that have been used to generate versatile coordination networks with metal ions offered simple way to develop AgNPs based potential colorimetric sensor environmental screening.RSC Advances 11/2014; 4(110). DOI:10.1039/C4RA13586E · 3.71 Impact Factor