Immunoresonance Scattering Spectrum Assay Of Microalbumin

PartⅠIntroductionThe principle and kinds of immunoassy, and the preparation, identification of colloid gold and the application of gold-labeled immunoassay were introduced. Some basic theory, characteristics, the application and the development of resonance scattering were summarized. The generation mechanism, clinical value and the analytical progress of microalbumin wre also reviewed.PartⅡA rapid and sensitive immunoresonance scattering spectral assay for microalbuminIn the presence of 75 mg/l polyethylene glycol (PEG), the immunoreaction of microalbumin (Malb) and its goat anti-human Malb antibody took place specifically in pH 4.4 buffer solution and aggregated to form immune complex particles that exhibit a strongest resonance scattering peak at 488 nm, and it was used to assay of Malb. The RS intensity at 488 nm (ΔI) was proportional to the Malb concentration (C) in the range of 0.03-0.96 mg/l, the regression equation wasΔI = 116.0C-2.1, the detection limit was 0.02 mg/l. Urine samples from 20 healthy subjects were assayed by this assay. The results were in agreement with those obtained with IT. This assay has been applied to detection of Malb in real samples, with simplicity, rapidity, high sensitivity and good selectivity.PartⅢA new immunonanogold resonance scattering quenching probe for rapid and sensitive assay of microalbuminA novel and sensitive immunonanogold resonance scattering spectral probe was obtained for rapid detection of microalbumin, using 10 nm gold nanaoparticle to label goat anti-human microalbumin. It was based on that the gold labeled anti-Malb took place nonspecific aggregation and exhibit a strong resonance scattering peak at 577 nm in pH 5.2 C6H8O7-Na2HPO4 buffer solution containing polyethylene glycol (PEG), and the immunocomplex formed after specific reaction of gold labeled anti-Malb with Malb, which caused the intensity of resonance scattering peak at 577 nm deceased evidently. The decreased resonance scattering intensity at 577 nm (ΔI577nm) was linear to the concentration of Malb in the range of 4-128 ng/mL, with a detection limit of 3.2 ng/mL. The proposed method was applied to detect Malb in health human urine sample with satisfactory results.PartⅣA resonance scattering immunoassay based on gold catalysis Cu2O-enhancement and its application in detection of MalbA novel resonance scattering immunoassay of microalbumin (Malb) based on gold catalysis copper(II)-glucose reaction which the precipitation of Cu2O on gold nanoparticle as tags was developed. After using 10 nm gold nanaoparticle to label goat anti-human microalbumin, which take placed unspecific aggregation in pH 5.0 C6H8O7-Na2HPO4buffer solutions. Adding Malb, the immunocomplex formed and dispersed after specific reaction of gold labeled anti-Malb with Malb. The products were centrifuged and the supernatant was used in the determination. In the present of 0.69mg/mL CuSO4,1.0 mg/mLNaOH (contain 13.84 mg/mL potassium sodium tartrate)and 0.088 mg/mL glucose solutions,the crystal seeds in supernatant catalysis coppe(rII)-glucose reaction, the signal amplification through the precipitation of Cu2O on the gold nanoparticles. The resonance scattering intensity at 610 (I610nm) increased greatly. The I610nm is proportional to the Malb concentration in the range of 0.014-0.43 ng/mL, with the detection limit of 7.2 pg/mL. The proposed method was applied to detect Malb in health human urine sample with satisfactory results.