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In this work, a core-shell quantum dot (QD, ZnS-CdS) was electrodeposited onto multiwalled carbon nanotube modified glassy carbon electrode (ZnS-CdS/MWCNT/GCE) and following glucose dehydrogenase (GDH) was immobilized onto QD modified electrode. The proposed electrode (GDH/ZnS-CdS/MWCNT/GCE) was effectively used for the photoelectrochemical biosensing of glucose in flow injection analysis (FIA) system using a home-made flow cell. Results from cyclic voltammetric and FI amperometric measurements have revealed that GDH/ZnS-CdS/MWCNT/GCE is capable of signaling photoelectrocatalytic activity toward NADH when the surface of enzyme modified electrode was irradiated with a light source (250W Halogen lamp). Thus, photoelectrochemical biosensing of glucose was monitored by recording current-time curve of enzymatically produced NADH at optimized conditions. The biosensor response was found linear over the range 0.010-2.0mM glucose with detection limits of 6.0 and 4.0μM for amperometric and photoamperometric methods, respectively. The relative standard deviations (n=5) for 0.5mM glucose were 5.8% and 3.8% for photoamperometric and amperometric results, respectively. The photoelectrochemical biosensor was successfully applied to the real samples. The results with this biosensor showed good selectivity, repeatability and sensitivity for monitoring glucose in amperometric and photoamperometric FIA studies., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this study, the electrochemical behavior of eugenol, a widely used herbal drug, was investigated at a pencil graphite electrode (PGE). A low-cost, disposable, sensitive and selective electrochemical sensor is proposed for the determination of eugenol by recording its differential pulse voltammograms in Britton-Robinson buffer solution containing 0.1 M KCl with pH of 2.0 at the PGE. The PGE displayed a very good electrochemical behavior with significant enhancement of the peak current compared to a glassy carbon electrode. Under experimental conditions, the PGE had a linear response range from 0.3 μM to 50.0 μM eugenol with a detection limit of 0.085 μM (based on 3S(b)). Relative standard deviations of 2.4 and 4.8% were obtained for five successive determinations of 30.0 and 5.0 μM eugenol, respectively, which indicate acceptable repeatability. This voltammetric method was successfully applied for the direct determination of eugenol in real samples. The effect of various interfering compounds on the eugenol peak current was also studied., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: There are scarce data about the prevalence of Hymenoptera venom allergy in the general population. The aim of this study was to determine the prevalence of Hymenoptera venom allergy in the general adult population of Istanbul., Methods: A total of 17,064 randomly selected telephone numbers were contacted and 11,816 (69.25%) individuals who agreed to participate completed a questionnaire. Those who disclosed hypersensitivity reactions due to Hymenoptera stings in this initial survey were called again and given another questionnaire. Those who were suspected of experiencing hypersensitivity reactions to Hymenoptera stings were invited for a clinical investigation with in vivo and in vitro diagnostic tests., Results: According to the first questionnaire, a total of 1171 (9.9%; 95% CI: 9.38-10.47%) were suspected of having a hypersensitivity to Hymenoptera stings. 51.75% (n: 606) answered the second questionnaire and 21% (n: 128) of these were still suspected of having a hypersensitivity to Hymenoptera stings (1.1%; 95% CI: 0.9-1.29%). The confirmed prevalence of hypersensitivity to Hymenoptera stings according to skin tests and in vitro sIgE levels was 0.2% (95% CI: 0.14-0.30%). Nearly all of the participants with systemic reactions were admitted to the emergency department, although only one tenth of them received adrenaline in the emergency room. 2.3% carried an adrenaline injector, whereas none of the patients received venom immunotherapy., Conclusions: The prevalence of Hymenoptera sting reactions in our geographical region is comparable with other European studies. There is a need to increase the awareness of adrenaline in the emergency management of insect sting anaphylaxis and venom immunotherapy in the prophylaxis., (Copyright © 2014 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.)

This study describes a new approach for the investigation of electrocatalytic oxidation of sulfide using a pencil graphite electrode modified with quercetin (PGE/QH(2)). Adsorption procedure was used for the preparation of the modified electrodes. It was observed that PGE/QH(2) showed a significant electrocatalytic activity toward sulfide oxidation. Cyclic voltammetric studies show that the peak potential of sulfide shifts from +450 mV at bare PGE to +280 mV at PGE/QH(2). The electrocatalytic currents obtained from amperometric measurements at +300 mV vs. Ag/AgCl/KCl(sat) and at pH 8.0 BR buffer solution containing 0.1M NH(4)Cl were linearly related to the concentration of sulfide. The calibration graph consisted of two linear segments of 1-20 μM and 20-800 μM with a detection limit of 0.3 μM (based on 3s(b)). The proposed method was successfully applied to the determination of sulfide in waste waters and was compared with the spectrophotometric method., (Copyright © 2012 Elsevier B.V. All rights reserved.)