İçeceklerde bulunan makrolid antibiyotiklerin moleküler baskılı elektrokimyasal sensörlerle seçici ve hassas tayini

FATMA BUDAK

İçeceklerde bulunan makrolid antibiyotiklerin moleküler baskılı elektrokimyasal sensörlerle seçici ve hassas tayini

Thesis Type: Doctorate

Institution Of The Thesis: Ankara University, Sağlık Bilimleri Enstitüsü, ANALİTİK KİMYA ANABİLİM DALI, Turkey

Approval Date: 2025

Thesis Language: Turkish

Student: FATMA BUDAK

Supervisor: Sibel Ayşıl Özkan

Open Archive Collection: AVESIS Open Access Collection

Abstract:

The most widely used drug group in the living world is antibiotics. Due to the excessive and widespread use of antibiotics, they pose a threat to living beings and the ecosystem. In addition, antibiotics are used to prevent and treat infectious diseases and microorganisms such as fungi and bacteria that cause infections. For this reason, antibiotics are generally widely used in humans, agriculture and animal husbandry. Due to the widespread use of antibiotics, they are found as residues in the environment and foods. Therefore, rapid and sensitive analysis of antibiotic residues is of great importance in terms of food safety and human health. In recent years, many analytical techniques have been used for accurate, reliable, sensitive, selective and rapid analysis of antibiotic residues in foods. Among these analytical techniques, electrochemical sensors are frequently preferred due to their excellent sensitivity, fast analysis times, reliability, ease of sample preparation and low organic solvent usage. However, these sensors still have deficiencies in terms of selectivity. In order to overcome these deficiencies, new and popular molecularly imprinted polymer sensors (MIPs) have begun to be used more in recent years. MIPs form a highly specific cross-linked polymeric structure with molecular recognition ability and target molecule. In this thesis, the applications and sensor designs of MIP-based electrochemical sensors for commonly used antibiotics (lincomycin (LIN), roxithromycin (ROK) and spiramycin (SPR)) in samples were investigated in detail. Both surface and electrochemical characterizations of the listed MIP system sensors for the antibiotics included in the thesis were examined using cyclic voltammetry (DV), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM) methods. Nanoparticle-doped MIP-based electrochemical sensor was used for LIN. In the study, firstly, CKE was combined and 5 µL AuNP was dropped and dried at room temperature. Then, the polymerization composition was prepared for the EP process. The polymerization solution was prepared by adding aniline (ANI, 0.1 M), LIN (1.0 mM) and 3-aminophenyl boronic acid (3-APBA, 1.0 mM) to pH 7.4 phosphate buffer solution (FT). Quantitative analysis was performed for the designed MIP tiled electrochemical sensor using both DPV and EIS methods. Selective, reliable, convenient operation, stable and sensitive features were demonstrated for both electrochemical methods. According to the results, the linearity range of the sensor was obtained between 1x10-12 M and 1x10-11 M for both methods. Detailed ROK/TiO2NP/ALG/CHIT@MIP/CKE sensor for ROK is easy to prepare, cheap, reliable, environmentally friendly and most importantly green. The results obtained in the studies conducted for ROK showed that the range of the sensors was between 1x10-13 M and 1x10-12 M, and the TS value was at a very low level of 1.51x10-14 M. Detailed validation studies were performed for the SPR/AuNP+CuNP/PRL/2-TBA@MIP/CKE sensor designed for SPR. In sensor design, EPization polymer method and DPV were used as analysis method. According to the findings, the linearity range of the sensor was obtained between 1x10-12 M and 1x10-11 M for both methods. In the sensors developed within the scope of the thesis, green strategies were used to create the most suitable materials for analyzing and applying template molecules with higher sensitivity and selectivity. While developing green strategies, molecular imprinting was performed using well-known, environmentally friendly and easily found materials in nature. In green chemistry, it is aimed to minimize toxic effects, energy consumption and environmental pollution by using materials found in nature. As a result; MIP-based electrochemical sensors developed for lincomycin, roxithromycin and spiramycin antibiotics have proven to be more advantageous, sensitive, selective and alternative methods compared to other methods.