▎ 摘　　要

Since brain natriuretic peptide (BNP) has become internationally recognized biomarkers in the diagnosis and prognosis of heart failure (HF), it is highly desirable to search for a novel sensing tool for detecting the patient's BNP level at the early stage. Here we report a platinum nanoparticles (PtNPs)-decorated reduced graphene oxide (rGO) field effect transistor (FET) biosensor coupled with a microfilter system for label-free and highly sensitive detection of BNP in whole blood. The PtNPs-decorated rGO FET sensor was obtained by drop-casting rGO onto the pre-fabricated FET chip and subsequently assembling PtNPs on the graphene surface. After antiBNP was bound to the PtNPs surface, BNP was successfully detected by the anti-BNP immobilized FET biosensor. It was found that the developed FET biosensor was able to achieve a low detection limitation of 100 fM. Moreover, BNP was successfully detected in human whole blood sample treated by a custom-made microfilter, suggesting the sensor's capability of working in a complex sample matrix. The developed FET biosensor provides a new sensing platform for protein detection, showing its potential applications in clinic sample.