Preparation of A Novel Sandwich-Type Electrochemical Immunosensor for AFP Detection Based on ATRP and Click Chemistry Technique
It is extremely important to explore the synthesis methodology and application scope of functional polymer brushes-based nanocomposites. In this work, an ultrasensitive sandwich-type electrochemical immunosensor based on polymer brush/graphene oxide (GO) nanoprobe was designed for quantitative detection of alpha fetoprotein (AFP). As the backbone of the polymer brush, polyacrylonitrile-g-GO (PAN-g-GO) was efficiently prepared via surface-initiated atom transfer radical polymerization (SI-ATRP). Benefit from the large number of nitrile groups in PAN, the poly (vinyltetrazole-co-hydroxyethyl methacrylate)-g-GO (P(VT-co-HEMA)-g-GO) was synthesized herein through nitrile click chemistry. Furthermore, the immunosensor reached the design requirements of high sensitivity through the P(VT-co-HEMA)-g-GO connected to plenty of signal labels. Importantly, the designed immunosensor showed a wide range (2.5×101-5×104 pg/mL) (R2 = 0.993) and a low detection limit (LOD, ~ 0.183 pg/mL) with high selectivity, good reproducibility and excellent stability. Therefore, these polymer brushes-based nanocomposites can provide potential applications for determining tumor markers (TMs) with robust signal amplification’s capability.