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This paper presents a novel ultrasensitive and rapid impedimetric biosensor with new immobilisation materials for parathyroid hormone (PTH) with the aim to determine the PTH level in serum for the diagnosis and monitoring of parathyroid diseases such as hyperparathyroidism, adenoma, and thyroid cancer. The interaction between PTH and the biosensor was investigated with an electrochemical method. The biosensor was based on the gold electrode modified by mercaptohexanol (6-MHL). Anti-parathyroid hormone (anti-PTH) was covalently immobilised onto a self-assembled monolayer (SAM) by using epiclorhidrina (EPI) with ethanolamine (EA). The EPI-EA interaction represents the first use of these for the construction of biosensors in published reports. The immobilisation of the anti-PTH was monitored by electrochemical impedance spectroscopy, cyclic voltammetry and scanning electron microscopy (SEM) techniques. After the optimisation studies of immobilisation materials such as 6-MHL, EPI, EA and glutaraldehyde, linearity, repeatability and sensitivity of biosensor were evaluated as the performance of biosensor. PTH was detected within a linear range of 0.1-0.6 pg/ml, and the detection limit was 0.1 fg/ml. The specificity of the biosensor was also investigated. Finally, the described biosensor was used to detect the PTH levels in artificial serum samples.

Calretinin (CAL) is calcium binding protein, and its levels in blood and cerebrospinal fluids are increased, since its expression is increased various cancer types. A novel biosensor system fabricated by immobilization of a specific antibody to CAL, anti‐Calretinin (anti‐CAL), onto a gold electrode surface via an effective covalent binding method using mercaptohexanol, epichlorohydrin, and ethanolamine was reported for the sensitive, selective, and accurate analysis of CAL. The proposed biosensor showed a linear calibration range between 1 ng/mL and 5 ng/mL. LOD and LOQ values were determined as 0.11 ng/mL and 0.38 ng/mL, respectively. The standard deviation related to the reproducibility of the new biosensor system was calculated as 3.95 %. Lastly, in order to state the applicability of the biosensor to early diagnosis of CAL in practice, artificial serum samples spiked with CAL have been analyzed by the proposed biosensor.

Thyroid-stimulating hormone (TSH) that regulates the synthesis of thyroid gland hormones controlling all metabolism is one of the pituitary hormones. Determination of TSH is crucial for monitoring thyroid gland-related disorders and some metabolic diseases.In this study, a non-labeled immunosensor based on covalent immobilization of anti-TSH antibody by using the formation of self-assembled monolayers (SAM) of 4mercaptophenylacetic acid (4-MPA) and functionalization of carboxyl ends with 1ethyl-3-(3-dimetilaminopropil) carbodiimide (EDC)/N-Hydroxysuccinimide (NHS) was fabricated for detection of TSH. Immobilization steps including the concentration of 4-2 MPA, the concentration of anti-TSH antibody and duration of anti-TSH antibody incubation were optimized by utilizing electrochemical impedance spectroscopy. Under optimal conditions, a sensitive, rapid and accurate determination of TSH at a concentration range between 0.7 -3.5 mIU/L was accomplished with a notable linearity and LOD value as 0.034 mIU/L as well as reproducibility and repeatability. Moreover, for comparison, linear range experiments were also carried out by using other electrochemical methods including Linear Sweep Voltammetry (LSV), Cyclic Voltammetry (CV) and capacitance spectroscopy (C). Finally, the constructed immunosensor was used for analyzing TSH levels spiked in the artificial serum samples.

Hava kirliliği, çeşitli kimyasal süreçler sonucunda oluşan ürünler tarafından havanın doğal bileşiminin bozulmasıdır. Bu bozulma biyolojik çeşitliliği ve doğal yaşamı olumsuz yönde etkilemektedir. Hava kirliliğine sebep olan hava kirleticilerinin maruz kalma süresi, derişim ve kimyasal özelliklerine bağlı olarak insan sağlığı üzerinde olumsuz etkileri bulunmaktadır. Bu çalışmanın amacı; hava kirliliğine sebep olan moleküllerden biri olan kükürt dioksitin Kırklareli il merkezindeki ölümler üzerine etkisinin incelenmesidir. Araştırma örneklemini, Kırklareli il merkezindeki 01.02.2014-31.01.2019 tarihleri arasında gerçekleşen, 18-85 yaş arasındaki 1381 bulaşıcı olmayan doğal ölüm vakası oluşturmuştur. Kükürt dioksit (SO2) seviyelerine ilişkin veriler Çevre ve Şehircilik Bakanlığının hava kalitesi izleme ağının internet sitesinden sağlanmıştır. Kükürt dioksit seviyelerinin, belirtilen tarihlerdeki aylara göre dağılımı ve ölüm sayıları ile olan bağıntısının saptanması SPSS 22.0 yazılımı kullanılarak gerçekleştirilmiştir. Araştırmanın analiz sonuçlarında 2014-2019 yılları arasındaki bazı aylarda kükürt dioksit (SO2) düzeyleri Dünya Sağlık Örgütü'nün (DSÖ) belirlediği sınır değerinin üzerinde olsa da yıllık ortalamaların sınır değerlerinin altında kaldığı açıkça gözükmektedir. Ölüm sayılarının yıllara göre değişimi ile yıllık ortalama kükürt dioksit seviyeleri arasındaki bağıntının değerlendirilmesi, yorumlanması ve kıyaslanması bu sınır değerleri göz önüne alınarak yapılmıştır.