Somatostatin ve Bazı Analoglarının Miktar Tayini İçin Elektroanalitik Yöntemler Geliştirilmesi

Abstract

Ozkan E., Development of Electroanalytical Methods for Quantification of Somatostatin and Some Analogs. Hacettepe University Graduate School of Health Sciences, Analytical Chemistry Program, PhD Thesis, Ankara, 2022. The growth hormone (GH) inhibitor somatostatin, which is among the therapeutic peptides, has an important place in the treatment of acromegaly and neuroendocrine tumors (NET). It slows down or stops tumor development in metastatic neuroendocrine cancers. It is also used to control hormone hypersecretion in pituitary tumors, endocrine pancreas and carcinoid tumors by inhibiting the release of somatostatin, acromegaly GH, insulin, glucagon and other hormones. MIPs are formed by imprinting polymerizing functional monomers in the presence of template molecules. When template molecules are removed from MIPs, cavities occur in the structure of the specific molecule in MIPs. In the thesis study, porous MIP-based electrochemical sensors were developed for the analysis of SOM, which is a GH inhibitor, and its synthetic analogues Octreotide (OC) and Lanreotide (LAN). N-methacryloyl-L-aspartic acid (MAAsp) and N-methacryloyl-L-glutamic acid (MAGA) were used as functional monomers to form the P(HEMA-MAAsp)@MIP/GCE, P(HEMA-MAGA)@MIP/GCE sensors, respectively, using the photopolymerization method on a glassy carbon electrode (GCE). The P(ANI)@MIP/GCE sensor was created by electropolymerization method, in which aniline (ANI) was used as a functional monomer. Then, template removal solution and time and incubation time were optimized to obtain higher efficiency from MIP sensors. It has been found that the developed MIP-based sensors give linear results, are precise, accurate, sensitive, selective, rugged and stable. In addition, the analytical performance of MIP sensors was investigated by comparing their electrochemical reactions with non-imprinted polymer (NIP). The applicability of the sensors to pharmaceutical preparation, commercial human serum and patient plasma samples has been demonstrated.