Determination of human IgG by solid substrate room temperature phosphorescence immunoassay based on an antibody labeled with nanoparticles containing Rhodamine 6G luminescent molecules

作者：Liu JM^*; Hui ZG; Wu AH; Li PP; Xu HH; Li LD; Liu ZB

来源：Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy , 2005, 61(5): 923-927.

DOI：10.1016/j.saa.2004.05.045

• luminescent nanoparticle
• solid substrate room temperature phosphorescence immunoassay
• human IgG
• rhodamine 60

Luminescent silicon dioxide nanoparticles (R-SiO2) with size of 50 nm containing Rhodamine 6G (R) were synthesized by sol-gel method. In the presence of Pb(Ac)(2) as a heavy atom perturber, the particle can emit intense and stable room temperature phosphorescence signal of R, respectively, on polyamide membrane, with the lambda(ex)(max)/lambda(em)(max) = 470/635 nm for R. Our research indicates that the specific immune reaction between goat-anti-human IgG antibody labeled with R-SiO2 and human IgG can be carried on polyamide membrane quantitatively, and the phosphorescence intensity was enhanced after the immunoreactions. Thus, a new method of solid substrate room temperature phosphorescence immunoassay (SS-RTP-IA) for the determination of human IgG was established basing on antibody labeled with the nanoparticles containing binary luminescent molecules. The linear range of this method is 0.0624-20.0 pg spot(-1) of human IgG (corresponding concentration, 0.156-50.0 ng mL(-1); sample volume, 0.40 muL spot(-1)). The regression equations of working curves are DeltaI(p) = 88.16. + 16.79m(1gG) (pg spot(-1)) (485/646 nm, r = 0.9997). Detection limits calculated by 3Sb/k are 0.017 pg spot(-1). For samples containing 0.156 and 50.0 ng mL(-1) of IgG, we measured repeatedly for 11 times, RSDs are 3.9 and 2.8%, respectively. This method is sensitive, accurate and of high precision.

• 出版日期2005-3
• 单位闽南师范大学; 清华大学