Solid-Phase Screening and Synthesis of Molecularly Imprinted Nanoparticles for Selective Recognition and Detection of Brain Natriuretic Peptide

A new recognition method is explored for the rapid detection of B-type natriuretic peptide (BNP) based on the rational design and solid-phase synthesis of molecularly imprinted nanoparticles (nanoMIP) encapsulated with carbon dots. The nanosized magnetic template is first prepared by attaching the epitope of BNP on amino-functionalized magnetic carriers. High-dilution polymerization of monomers in the presence of magnetic template generates lightly crosslinked imprinted nanoparticles. To obtain the optimal MIP formulation, a new combinatorial screening approach is developed by a competitive fluorescence assay using the magnetic template. The resultant nanoMIP exhibits high affinity and selectivity toward BNP with an equilibrium dissociation constant (K-D) of approximate to 10(-11) m. The proposed assay allows fast BNP detection within approximate to 7 min with a linear range of its concentration from 0.25 to 5000 pg mL(-1) and a limit of detection of 0.208 pg mL(-1) (S/N = 3). To demonstrate its practicability in clinical diagnosis, unknown real serum samples from 160 individuals are analyzed and the relative standard deviation is less than 4.43%. Compared with the routine electrochemiluminescence detection method that is widely used in hospital, the relative error is less than 4.98% and the correlation coefficient is 0.994.

Automated summary

A new recognition method for rapid detection of B-type natriuretic peptide (BNP) using molecularly imprinted nanoparticles (nanoMIP) encapsulated with carbon dots is explored. The nanoMIP exhibits high affinity and selectivity toward BNP with a detection limit of 0.208 pg mL(-1). Real serum samples from 160 individuals are analyzed, and the method shows high accuracy and reliability compared to the routine electrochemiluminescence detection method.