| 초록 |
Postranslation of proteins plays an important role in their correct folding and functions. Using proinsulin as a model, we here report a nanoplasmonic biosensor to (i) detect serum insulin concentration and (ii) monitor a conformational conversion from proinsulin to mature insulin. The basis of the sensor is based on plasmonics-based refractometric sensor due to binding, conformational changes of insulin on the sensor surface. The limit of detection for insulin in the serum increases from 100 fM (primary response) to 1 fM (100 times) after enhancement by the immunogold colloids. The probes of anti-C peptide-antibody-nanoparticle conjugates are used to detect proinsulin in the mixture with mature insulin at 20 fM. Moreover, real time monitoring for the conformational conversion from proinsulin to mature insulin reveals misfolded insulin, C-peptide mutant sites and kinetics of the conversion. |
