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.

Lateral flow assays (LFAs) are an ideal choice for drug abuse testing favored by their practicability, portability, and rapidity. LFA based on-site rapid screening devices provide positive/negative judgment in a short response time. The conventionally applied competitive assay format used for small molecule analysis such as abused drugs restricts the quantitation ability of LFA strips. We report herein, for the first time, a new strategy using the noncompetitive assay format via a biomimetic material, namely, poly(p-phenylene) β-cyclodextrin poly(ethylene glycol) (PPP-CD-g-PEG) combined with gold nanoparticle (AuNP) conjugates as the labeling agent to recognize the target cocaine molecule in the test zone. The intensities of the visualized red color in the test line indicate that the cocaine concentrations were analyzed via a smartphone application. Significantly, a combination of this platform with a smartphone application provides quantitative data on the cocaine amount, making it a very inventive and attractive approach especially for on-site applications at critical points such as traffic stops and the workplace.

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The fabrication of electro and bioactive surfaces by electrochemical deposition of the thiophene-functionalized polyphenylalanine macromonomer (T-g -PPhe) is reported. The resulting conducting graft copolymer, polythiophene-graft -polyphenylalanine (PT-g -PPhe) formed on the indium tin oxide (ITO) glass surface, is characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and fl uorescence microscopy. Then, possible uses of PT-g -PPhe as matrices in the sensor design for both electrochemical biosensing and cell adhesion studies are investigated. In the fi rst part, PT-g -PPhe that is deposited on ITO is further functionalized with the arginylglycylaspartic acid peptide via 1-Ethyl-3-(3 dimethylaminopropyl) carbodiimide for the selective cell adhesion. Immunofl uorescence staining is performed to detect the difference between adherences of "integrin αvβ3" receptor positive (U87-MG) and negative (HaCaT) cell lines on to the biofunctional surface. In the second part, an electrochemical glucose sensor is constructed by immobilizing glucose oxidase on the surface of PT-g -PPhe, which is deposited on a glassy carbon electrode.