Acetylcholinesterase (AChE) and choline oxidase (ChO) were co-immobilized on platinum nanoparticles (PtNPs) and metallic organic framework (MOF) modified Au electrode to construct an acetylcholine (ACh) biosensor. The morphology and structure of the nanoparticles modified working electrode were characterized by Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), Cyclic voltammetry (CVs) and Electrochemical Impedance Spectroscopy (EIS) techniques. The prepared biosensor exhibit a wide linear range of 0.01-500 mu M for acetylthiocholine chloride (ATCl) and a low detection limit of 0.01 mu M. No interferences were observed for other possible compounds/substances present in the serum samples. For detection of ACh in clinical (serum) samples the results of the nanoparticle based biosensor were well correlate with the results obtained from HPLC method. The half-life of the working electrode was 4 months, when stored at 4 degrees C. (C) 2018 Elsevier B. V. All rights reserved.