We report a novel sensing platform for biosensor and pseudocapacitor application based on electron beam (EB) irradiated polypyrrole/cerium-nickel@modified guar gum (EB-PPy/Ce-Ni@MGG) nano-biocomposite. The EB irradiated PPy nanospheres (NSs) and Ce-Ni bimetallic NSs prepared are functionalized into the amine MGG matrix film for the improvisation of energy storage as well as charge transfer mechanism. MGG film also found to be an effective conducting material in composite formation like reduced graphene oxide (r-GO) with excellent electrocatalytic activity. The nanobiocomposite was confirmed by SEM, EDAX, XRD, Raman and FT-IR analysis. Interestingly, the EB-PPy/Ce-Ni@MGG modified glassy carbon electrode exhibited an excellent electrocatalytic activity towards the simultaneous sensing of hydroquinone, catechol, resorcinol and nitrite with lower detection limits as 87 nM, 84 nM, 518 nM and 786 nM. Furthermore, EB-PPy/Ce-Ni@MGG modified Ni foam electrode was evaluated in 1 M NaOH by cyclic voltammetry and galvanostatic charge-discharge methods for pseudocapacitor application. The Ce-Ni bimetal NSs in the EB-PPy@MGG shows a significant improvisation of specific capacitance to 605 Fg(-1) at a current density of 1 Ag-1. The optimized electrolyte concentration, current density, scan rate and cycle stability shows promising results to low cost energy storage with wearable power device fabrication. (C) 2017 Elsevier Ltd. All rights reserved.