Electroanalytical technologies as a beneficial subject of modern analytical chemistry can play an important role for abused drug analysis which is crucial for both legal and social respects. This article reports a novel aptamer-based biosensing procedure for cocaine analysis by combining the advantages of aptamers as selective recognition elements with the well-known advantages of biosensor systems such as the possibility of miniaturization and automation, easy fabrication and modification, low cost, and sensitivity. In order to construct the aptasensor platform, first, polythiophene bearing polyalanine homopeptide side chains (PT-Pala) was electrochemically coated onto the surface of an electrode and then cocaine aptamer was attached to the polymer via covalent conjugation chemistry. The stepwise modification of the surface was confirmed by electrochemical characterization. The designed biosensing system was applied for the detection of cocaine and its metabolite, benzoylecgonine (BE), which exhibited a linear correlation in the range from 2.5 up to 10 nM and 0.5 up to 50 μM for cocaine and BE, respectively. In order to expand its practical application, the proposed method was successfully tested for the analysis of synthetic biological fluids.

As found in other countries, alcohol dependence in Turkish subjects with childhood ADHD starts early and is relatively resistant to treatment. Early diagnosis and treatment of ADHD might help prevent alcohol- and substance-related disorders.

A designed bio-functional surface is a promising candidate forcell-culture-on-a-chipapplications.

In the present study, two amphiphilic star-hyperbranched copolymers, poly(methyl methacrylate)-b-poly(2-hydroxyethyl methacrylate) (PMMA-b-PHEMA), with different hydrophilic PHEMA segment content (PMMA-b-PHEMA-1, and PMMA-b-PHEMA-2) were synthesized and their drug loading and release profiles were examined by using paclitaxel (PTX) as a model drug. Drug loading capacity and encapsulation efficiency were found to be similar in both polymers. Encapsulation efficiency found to be prominent with 98% and 98.5% for PMMA-b-PHEMA-1 and PMMA-b-PHEMA-2, respectively. On the other hand, drug release behaviors were varied in favor of the block copolymer comprising shorter PHEMA chains (PMMAb-PHEMA-1). Additionally, to assess biological effects of PTX-loaded polymers, human non-small cell lung carcinoma (A549) cells were used. Cell viability and cell cycle analysis showed that both polymers were not toxic to the cells. Cytotoxic effects of PTX-loaded PMMA-b-PHEMA-1 on A 549 cells were higher (66.49% cell viability at 5.0 ng/mL PTX) than that of PMMA-b-PHEMA-2 (72.47% cell viability at 5.0 ng/mL PTX) consistent with the drug release experiments.