Au nanoparticles modified with 4-mercaptopyridine and 6-mercapto-1-hexanol were used as coordination agents to prepare a novel hybrid nanomaterial with Ag:4,4'-bipyridine nanobelts. This nanohybrid was employed to modify glassy carbon electrodes and to construct a horseradish peroxidase-based mediatorless amperometric biosensor for H2O2. The electrode, poised at -100 mV, exhibited a rapid response within 4 s and a linear calibration range from 90 pM to 6.5 nM H2O2. The biosensor showed a high sensitivity of 283 A/M cm(2) and a very low detection limit of 45 pM at a signal-to-noise ratio of 3. The enzyme biosensor showed high stability when stored at 4 degrees C under dry conditions, retaining over 96% and 78% of its initial activity after 15 and 30 days of storage at 4 degrees C, respectively. (C) 2016 Elsevier Inc. All rights reserved.