POLİ (METİL METAKRİLAT) TABANLI MİKROÇİP KULLANARAK YÜZEYDE GÜÇLENDİRİLMİŞ RAMAN SPEKTROSKOPİSİ ÖLÇÜMÜNE DAYALI LUTEİNİZAN HORMON TAYİNİ
Özet
Proteins form many physical and chemical events at the molecular level. The presence of low concentrations of proteins in the environment and complex interactions lead to the development of alternative techniques for the analysis of biomolecules. The World Anti-Doping Agency (WADA) has received a protein class of luteinizing hormone (LH) in the list of prohibited substances for male athletes. Gonadotropin LH, one of the many hormones, is produced by the anterior pituitary gland and is used as doping material since it allows testis to convert cholesterol to testosterone in Leydig cells, thereby increasing blood oxygen carrying capacity. In this study, a sandwich type biosensor based on immunomagnetic separation and Raman labeling for hLH assay was developed. A method has been developed to make homogeneous sandwich formation, washing process and surface enhanced Raman spectroscopy (SERS) signal measurement in poly (methyl methacrylate) based (PMMA), four chambered microchips connected with capillary valves. For the formation of homogenous sandwich structure, nanoparticles and gold nanoparticles with magnetic properties were synthesized in laboratory and necessary modifications were made. 4-Aminothiophenol (4-ATP) Raman labeling was used to follow the SERS signals. The signal intensity of the C-S group against hLH concentrations of 4-ATP at 1086 cm-1 was plotted on a chart and calibration graph was created. The correlation between hLH concentrations (0-250 IU/L) and SERS signals were linear in the Biorad originated control serum samples (R2 = 0.9942). This study is presented as a new method of analysis after tested in artificial human serum samples for selectivity, sensitivity, and applicability.