Development of The Dual-labeling Time-resolved Fluoroimmunoassay for Detection of C-peptide and Insulin and Its Initially Application

作者:Ma Qiang; Li Lai-Qing; He An; Lin Guan-Feng; Zou Li-Ping; Li Ming; Wu Ying-Song*
来源:Progress in Biochemistry and Biophysics, 2011, 38(7): 670-676.
DOI:10.3724/SP.J.1206.2011.00037

摘要

To simultaneously detecting the C-peptide and insulin in human serum, a dual-labeling time-resolved fluoroimmunoassay (TRFIA) for detection of C-peptide and insulin was preliminary founded. Two capture monoclonal antibodies were mixed together and then coated in human serum. Two counterpart tracer monoclonal antibodies, were labeled with Eu3+ (anti-Insulin) and Sm3+ (anti-C-peptide) chelates, respectively. The double antibody sandwich in one step method was used to develop the TRFIA for simultaneously detection of the C-peptide and insulin in human serum. These results showed that sensitivity of C peptide analysis was up to 0.2 mu g/L, linear range is 0.5 similar to 22 mu g/L, the recovery percent is 99.6%, The intra- and inter-assay coefficient of variation were 4.6%similar to 6.0% and 5.1%similar to 7.6%, respectively; sensitivity of insulin analysis was up to 0.8 mU/L, linear range is 3.6 similar to 180 mU/L, the recovery percent is 99.4%, the intra- and inter-assay coefficient of variation were 3.7%similar to 6.0% and 5.1%similar to 8.0%, respectively. Moreover, 200 samples were tested by the self-made and commercially available C-peptide and insulin kit (PerkinElmer) kits at the same time. The correlation coefficient was 0.98 and 0.99, respectively. In conclusion, the self-made dual-labeling time-resolved fluoroimmunoassay for simultaneously detection of C-peptide and insulin might be a simple, sensitive and rapid method for rapid diagnosis for the diabetes caused by the lack of insulin secretion, it would also provide an alternative route for serology high-screening of the samples for C-peptide and insulin in clinical application.