The Estabishment Of The Detection Of Kidney Disease Effctive Marker-cystatin C

Currently,the kidney disease is so serious that it is harmful to the health of human beings.Glomerular filtration rate(GFR)is an index which is commonly used to estimaterenal function.Cystatin C(Cys-C)is being considered as a special biomarker for GFR.There are a lot of methods to measure Cys-C.But these methods have been found many disadvantages.The purpose of thesis was to establish a method to detect Cys-C with the low cost,easy operation and speciality.The specific sequence of affinity ligand of Cystatin C was obtained by selection of the Ph.D.-12 Phage Display Peptide Library.After three rounds of panning,we gained a Cys-C specific peptide sequence:Q-V-N-G-L-G-E-R-S-Q-Q-M.The peptide was synthesized by the manual way,coupled with FITC as a fluorescent probe:FITC-Acp-Q-V-N-G-L-G-E-R-S-Q-Q-M.With high pressure liquid chromatography and mass spectrometry measuring,molecular weight of the probe is coincided with the theoretical value.When the concentration of the Cys-C was in the range of 0.039-2.5 μg/mL,keeping with the linear equation:y = 182.12 x + 33.842,R2 was 0.9990.There was significant positive linear correlation between fluorescence intensity and the concentration of Cys-C.Similarly,when the concentration of the Cys-C was in the range of 2.5 μg/mL-160μg/mL,keeping with the curve equation:y = 599.3 ln(x)-119.79,R2 was 0.9964.In all,fluorescence intensity had correlated positively with the concentration of Cys-C.It can provide a new method to effectively detect Cystatin C.