Kurkumin Tayinine Yönelik Yüzey Plazmon Rezonans Temelli Nanosensörlerin Hazırlanması

Abstract

Herbal ingredients are among the most used products in alternative and complementary medicine. Curcumin, which is obtained from Curcuma longa plant known as Indian saffron or turmeric, has become quite popular in recent years due to its anticancer and antioxidant properties. Because of its ability to interact with molecular targets in various fields, it has a supportive effect on chemotherapy with different mechanisms in many types of cancer. Moreover its extraordinary effects on health, turmeric is an important spice marketed as dry turmeric in the world cuisine. There are many products which are containing turmeric in the market, both in the field of health and gastronomy. However, turmeric powder can be mixed with foreign starch and different spices as well as powders of some other Curcuma types these products. This situation threatens public health and decreases the quality of economically and socially. Therefore, it is important to control commercial products which are containing turmeric produced in violation of the legislation and their permitted properties. In this study, it was aimed to develop a sensitive and fast, new nanosensor method for the detection of curcumin using with surface plasmon resonance spectroscopy. iv For this purpose, curcumin-imprinted and non-imprinted SPR nanosensors were prepared. After the characterization studies of the prepared nanosensors were carried out with zeta sizer analysis, scanning electron microscope, contact angle, ellipsometer, atomic force microscope and fourier transform infrared spectroscopy, kinetic studies were started. The percent of refraction, symbolized by (%)ΔR, was determined by the sensograms obtained after the measurements made in the kinetic studies. According to the results obtained, a linear calibration graph with an R2 value of 0.99 was drawn and the LOD was calculated as 0.0012 mg/L and the LOQ value as 0.0040. In addition, in selectivity studies, the specificity of curcumin-imprinted nanosensors designed with sunset yellow and tartrazine dyes was demonstrated. In real samples were obtained from the market, the recovery rate of the work done, in other words, its efficiency was also tested. Thus, the high recovery rates calculated as percentages revealed the reliability of the study. In addition, validation studies of curcumin-imprinted SPR nanosensors in real samples were performed using with liquid chromatography-tandem mass spectrometry (LC-MS). Consistent results have proven that SPR nanosensors are sensitive and highly accurate. The minimal variation of the diffraction value as a result of the kinetic analyzes carried out in the reusability studies within the scope of the thesis revealed the usability of SPR nanosensors in food analysis. In this study, it has been shown that there is a fast, sensitive, easy and cost-effective analysis method with curcumin imprinted SPR nanosensors.