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An enzymeless electrochemical sensor for detection of low amounts of H 2 O 2 with the aid of Ag nanoparticles supported on conducting poly(vinylferrocene) (PVF) film was developed. Experimental results revealed that contribution of Ag nanoparticles led to remarkable improvement by means of reduction potential and reduction current. Influence of experimental parameters (i.e. polymeric film thickness, concentration of Ag precursor, immersion time in precursor solution, reduction time, and reduction potential) were investigated. The Ag/PVF-modified electrode system was characterized physically by scanning electron microscopy. The results revealed that the sensor developed was easyto-prepare, economic, selective, and sensitive, with a fast response time of 3 s. The linear concentration range of the sensor was 0.1-50 mM, with a sensitivity of 14.1 µ A mM −1 and a limit of detection of 0.94 µ M. Finally, interference effects of uric acid, ascorbic acid, dopamine, and glucose molecules were studied and no significant interference was observed at physiological levels.

Background:: new and selective electrochemical sensor was developed for the determination of levocetirizine dihydrochloride, which is an antihistaminic drug. Method:: The investigation was performed by using cyclic, differential pulse and square wave voltammetric methods on the β-cyclodextrin modified glassy carbon electrode. It is thereby planned to obtain information about levocetirizine determination and its mechanism. Result:: The efficiency of experimental parameters including pH, scan rate, and accumulation potential and time on the anodic response of levocetirizine dihydrochloride was studied. By employing the developed method and under optimized conditions, the current showed linear dependence with a concentration in the range between 2 × 10-8 M and 6 × 10-6 M in pH 2.0 Britton Robinson (BR) buffer. Conclusion:: The achieved limits of detection and quantification were found as 3.73 × 10-10 M and 1.24 × 10-9 M, respectively. In addition, the possibility of applying the developed sensor for real sample analysis was investigated, so β-cyclodextrin modified glassy carbon electrode was used to determine levocetirizine dihydrochloride in Xyzal® tablet dosage form. Finally, this sensor was successfully applied to the real sample as a selective, simple, reproducible, repeatable electrochemical sensor.

Desloratadine is one of the most effective second‐generation antihistamines and the electrochemical behavior of the active agent of desloratadine was investigated with a new nanosensor designed with the addition of zinc oxide and multiwalled carbon nanotube (ZnO : MWCNT) mixture on glassy carbon (GCE). By investigating and using cyclic, differential pulse and square wave voltammetry techniques with ZnO : MWCNT/GCE, it is planned to obtain information about quantification and mechanism of desloratadine. The efficiency of experimental parameters such as pH, scan rate, accumulation potential and time on the anodic response of desloratadine were studied. Differential pulse voltammetry was selected as assay method and under developed method and optimized conditions, the current showed linear dependence with concentration in the range between 2×10−8 and 8×10−6 M in pH 5.5 acetate buffer. The achieved limits of detection (LOD) and quantification (LOQ) are 0.769 nM and 2.56 nM respectively. Applicability of the methods was demonstrated by their implementation in pharmaceutical dosage forms of desloratadine and the accuracy, precision, selectivity, sensitivity, intra‐day and day‐to‐day reproducibility of the methods were clearly explored. Finally, this sensor was successfully applied on real sample as a selective, simple, reproducible, repeatable an electrochemical sensor.

B u çalışmada daha önce geliştirilmiş olan Pt@PVF katalizörünün katalitik özelliklerinin geliştirilmesi için kalem grafit elektrot üzerinde poli(vinilferrosen)-destekli Pt ve Pd bimetalik katalizörü (PtPd@PVF) elektrokimyasal olarak hazırlanmıştır. Pt ve Pd kaynağı olarak K 2 PtCl 4 ve K 2 PdCl 4 kullanılmış ve metallerin iletken polimer yüzeyine disperse edilmesi için dönüşümlü voltametri tekniği kullanılmıştır. Pt ve Pd komplekslerinin indirgenmesi için elektrokimyasal ve kimyasal indirgeme yöntemleri karşılaştırılmıştır. Hazırlanan katalizör sisteminin elektrokimyasal karakterizasyonu için dönüşümlü voltametri kullanılmış olup fiziksel karakterizasyon içinse taramalı elektron mikroskobu görüntüleri ve enerji dağılımlı X-ışınları spektrumu kullanılmıştır. Monometalik Pt@PVF katalizörü ile karşılaştırıldığında, PtPd@PVF katalizörünün metanolün elektroyükseltgenmesi için daha yüksek katalitik aktivite gösterdiği gözlenmiştir.