Detection of CRISPR-Cas9-Mediated Mutations Using a Carbon Nanotube-Modified Electrochemical Genosensor.

The CRISPR-Cas9 system has facilitated the genetic modification of various model organisms and cell lines. The outcomes of any CRISPR-Cas9 assay should be investigated to ensure/improve the precision of genome engineering. In this study, carbon nanotube-modified disposable pencil graphite electrodes (CNT/PGEs) were used to develop a label-free electrochemical nanogenosensor for the detection of point mutations generated in the genome by using the CRISPR-Cas9 system. Carbodiimide chemistry was used to immobilize the 5'-aminohexyl-linked inosine-substituted probe on the surface of the sensor. After hybridization between the target sequence and probe at the sensor surface, guanine oxidation signals were monitored using differential pulse voltammetry (DPV). Optimization of the sensitivity of the nanogenoassay resulted in a lower detection limit of 213.7 nM. The nanogenosensor was highly specific for the detection of the precisely edited DNA sequence. This method allows for a rapid and easy investigation of the products of CRISPR-based gene editing and can be further developed to an array system for multiplex detection of different-gene editing outcomes

What determines return risks for bank equities in Turkey?

By using data from thirteen publicly traded commercial and deposit banks this paper estimates the determinants of market risk for banks' equities in the case of an emerging market economy, Turkey. The analysis reveals that maturity composition of banks' loans, share of trading income in banks' overall revenue stream and its foreign-ownership structure are important indicators of the volatility of its equity returns. Banks with shorter loan maturity positions are regarded by investors as safer companies to invest in while increases in trading income as a source of banks' overall revenue increases the volatility of its equity returns. Foreign ownership of a bank also lowers its equity return risk

Electrochemical detection of enzyme labeled DNA based on disposable pencil graphite electrode

WOS: 000230017500030PubMed ID: 15907640Electrochemical biosensor for the detection of DNA hybridization using the reduction signal of a-naphthol is described. A pencil graphite electrode was used as a working electrode. Capture probes were covalently attached on to the pencil graphite electrode surface (PGE) at the 5' end amino group by using N-(dimethylamino)propyl-N'-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysulfosuccinimide (NHS) as a coupling agent on to PGE. After capture probe immobilization on to PGE surface; probe was hybridized with complementary biotinylated oligonucleotide. Alkaline phosphatase labeled with extravidin (Ex-AP) binds to biotinylated hybrid via biotin-avidin interaction. alpha-Naphthyl phosphate (alpha-NAP) was added and the reaction between alkaline phosphatase (AP) and alpha-NAP was occurred consequently as a substrate of AP, alpha-NAP reduction signal was obtained from this reaction, at -0.100 V by using differential pulse voltammetry (DPV). Other experimental parameters were studied such as; optimizations of hybridization time, and the concentrations of capture probe, biotinylated oligonucleotide and enzyme. (c) 2005 Elsevier B.V All rights reserved