▎ 摘　　要

NOVELTY - Nanomaterial based ractopamine detecting electrochemical sensor, prepared by modifying glass carbon electrode surface with nano gold particles and prepared graphene-Prussian blue-chitosan complex, and dripping ractopamine antigen on modified electrode to obtain ractopamine detecting electrochemical sensor is claimed. The preparation of electrochemical sensor comprises e.g. preparing graphene-Prussian blue-chitosan complex, pretreating the glass carbon electrode, depositing gold nano particles on the glass carbon electrode, and depositing complex on nano gold plated glass carbon electrode. USE - Used as nanomaterial based ractopamine detecting electrochemical sensor. ADVANTAGE - The sensor contains graphene material which is easily dispersed, large specific surface area, high load of the electric active material and the biological molecule, providing more uniform, larger electro-active site distribution, and biocompatibility of the nano gold particles to accelerate electronic transmission rate to prepare modified glass carbon electrode surface, thus improving the sensor sensitivity; can detect ractopamine with concentration range of 0.3-1x 103 ng/ml, which can be used for detecting target component of ractopamine in the actual sample. DETAILED DESCRIPTION - Nanomaterial based ractopamine detecting electrochemical sensor, prepared by modifying glass carbon electrode surface with nano gold particles and prepared graphene-Prussian blue-chitosan complex, and dripping ractopamine antigen on modified electrode to obtain ractopamine detecting electrochemical sensor is claimed. The preparation of electrochemical sensor comprises (i) preparing graphene-Prussian blue-chitosan complex, (ii) pretreating the glass carbon electrode, (iii) depositing gold nano particles on the glass carbon electrode, (iv) depositing graphene-Prussia-chitosan complex on nano gold plated glass carbon electrode obtained in step (iii), to obtain modified glassy carbon electrode, (v) dropping the ractopamine antigen on modified glassy carbon electrode, drying for 5 hours to obtain the ractopamine electrochemical sensor. INDEPENDENT CLAIMS are also included for: (1) preparing nanomaterial based ractopamine detecting electrochemical sensor comprising (i) preparing graphene-Prussian blue-chitosan complex: uniformly dispersing the graphene with chitosan and Prussian blue composite film, (ii) pretreating the glass carbon electrode: polishing the glass carbon electrode with 0.3 and 0.05 mu m aluminum oxide powder suspension respectively, ultrasonic cleaning in mixed solution of distilled water and ethanol for 10 minutes, using cyclic voltammetry for determination of Ep1-Ep2 85mV requirements, (iii) carrying out electrodeposition: depositing nano gold particles in 1% chloroauric acid solution, using the chronoamperometry method, reducing auric ion to gold on the electrode surface, washing using distilled water for 10 minutes to remove physically adsorbed gold to obtain nano gold deposition electrode, (iv) dropping 10 mu l chitosan Prussian-graphene composition solution to the surface of modified electrode, drying for 2 hours, adding 10 mu l 100 ng/ml ractopamine antigen solution to the modified electrode surface, drying for 5 hours, dropping 10 mu l 0.1% bovine serum albumin binding with non specific binding sites on electrode surface, and obtaining the ractopamine electrochemical sensor, and (v) detecting antigen by two test conditions i.e. concentration and incubation time using ractopamine electrochemical sensor, the detection of ractopamine in fixed antigen concentration is 100 ng/ml and the incubation time is 40 minutes; and (2) detecting ractopamine using electrochemical sensor comprising (i) post-processing pork sample: providing 5 g sample and placing in a 50 ml centrifugal tube, adding in 15 ml acetonitrile oscillator, violent vibrating for 10 minutes, centrifuging at 4200 revolutions/minute for 5 minutes, taking supernatant into another centrifuge tube, adding 2.0 g sodium chloride and 10 ml n-hexane, violent vibrating using vibrator for 10 minutes, centrifuging at 4200 revolutions/minute for 10 minutes, absorbing intermediate acetonitrile layer 12.0 ml into another centrifugal tube, drying by nitrogen blowing, and dissolving using phosphate buffered saline (PBS) buffer solution, (ii) detecting sample: under the optimal condition: fixed antigen concentration is 100 ng/ml, incubation time is 40 minutes, detecting the pork sample, and (iii) establishing corresponding linear relation, calculating the corresponding sample of ractopamine residue.