Molecular Imprinting Sensor Of Barbiturate Drugs

Molecular imprinting electrochemical analysis was a newly developed discipline, it mainly used the electrochemical method to study the organic small molecules.In this paper according to the scientific results of the molecularly imprinted electrochemical sensor and molecular imprinting technology. Prepared barbiturate drugs molecularly imprinted electrochemical sensor based on the obtained mature conditions was in a simple way, studied the feasibility of this sensor and characterization of molecularly imprinted membrane structure.As follow showed the main content:1. A specificity molecularly imprinted polymer(MIP) film for the determination of phenobarbital was electropolymerized on a glassy carbon electrode using methacrylic acid as a functional monomer, ethylene glycol maleic rosinate acrylate as a cross-linking agent. The optimum experimental conditions were explored. Under the optimum experimental conditions, the response performances of the sensor for phenobarbital recognition were investigated by cyclic voltammetry(CV), differential pulse voltammetry(DPV) and electrochemical impedance spectroscopy(EIS). The results show that the molecularly imprinted films exhibit a quick response, a good sensitivity and selectivity to the template molecule phenobarbital. Differential pulse voltammetry(DPV) results present that the linear detection range of phenobarbital concentration was in the range of 8.0×10-7 ~ 1.0×10-4 mol/L(Linear regression coefficient = 0.9983) with the detection limit(S/N = 3) of 5.4×10-8 mol/L. The prepared sensor was successfully applied to the determination of phenobarbital in practical samples with recovery ranging from 95.7% ~ 105.0%.2. To improve the sensitivity, a Cu O nanoparticle doped in molecularly imprinted polymer(MIP) film for the determination of phenobarbital was prepared by using methacrylic acid as functional monomers, ethylene glycol maleic rosinate acrylate as a cross linking agent by thermal polymerization method. The electrochemical properties of the nano-doped sensor were investigated using cyclic voltammetry(CV), differential pulse voltammetry(DPV), electrochemical impedance spectroscopy(EIS) and chronoamperometry(CA). The chemical structures and morphologies of the imprinted films were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. The results indicated that the sensors response value of peak current shows a linear dependence on the phenobarbital concentration in the ranges of 1.2×10-7 ~ 1.5×10-4 mol/L of phenobarbital.(Linear regression coefficient = 0.9984) with the detection limit(S/N = 3) of 8.2×10-9 mmol/L. The prepared sensor was successfully applied to the determination of phenobarbital in practical samples with recovery ranging from 96.5% to 103.0%.3. To improve the sensitivity of molecular imprinted electrochemical sensor, a molecularly imprinted polymer(MIP) film for the determination of phenobarbital(PB) was electropolymerized on Cu O nanoparticle modified glassy carbon electrode by using methacrylic acid(MAA) as functional monomer, ethylene glycol maleic rosinate acrylate(EGMRA) as a cross-linking agent in the presence of supporting electrolyte(tetrabutylammonium perchlorate- TBAP). The electrochemical properties of Cu O nanoparticle modified molecularly imprinted and non-imprinted polymer(NIP) sensors were investigated by cyclic voltammetry(CV), differential pulse voltammetry(DPV) and electrochemical impedance spectroscopy(EIS). The results show that the electrochemical properties of Cu O nanoparticle modified molecularly imprinted polymer sensor were completely different with those of NIP sensors. The morphology of Cu O nanoparticle modified molecularly imprinted polymer sensor was examined under a scanning electron microscope(SEM). The Cu O nanoparticles were distributed uniformly at the surface, and improved recognitive sites of modified molecularly imprinted polymer sensor. Response value of DPV peak current shows a linear dependence on the phenobarbital concentration in the range of 1.0×10-8 ~ 1.8×10-4 mol/L of phenobarbital.(Linear regression coefficient = 0.9994) with the detection limit(S/N = 3) of 2.3×10-9 mmol/L. The results indicated that the Cu O nanoparticle modified molecularly imprinted polymer sensor is one of the highest sensitive and selective sensors for the PB determination. The prepared sensor was successfully applied to the determination of phenobarbital in practical samples with recovery ranging from 95.0% to 102.5%.4. A novel sensor is developed for detection amobarbital in urines, which is based on an electropolymerized molecularly imprinted polymer(MIP) on the surface of the Cu O nanoparticles modified glassy carbon electrode. The optimums film formed conditions and experimental conditions were explored. The surface feature and performance of the modified electrode was characterized by scanning electron microscope(SEM) 、 cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS). The electrochemical measurements indicated that Cu O nanoparticles had good sensitization effected for the molecularly imprinted sensor and this sensors exhibit a good sensitivity and selectivity to the template molecule amobarbital. In the optimal conditions, the relative redox peak currents of hexacyanoferrate were linear. The concentration of amobarbital ranged from of 1.0×10-7 mol/L to 1.4×10-4 mol/L, with a linear correlation coefficient of 0.9966. The detection limit was 2.1×10-9 mol/L(S/N = 3). The prepared sensor was successfully applied to the determination of amobarbital in urine samples with recovery ranging from 94.00% to 104.67%.5. Synthesized uniform nickel nanoparticles modified Glassy Carbon. And then thermal polymerization film base on a Cu O nanoparticle doped molecularly imprinted polymer(MIP) film for the determination of Amobarbital was prepared by using methacrylic acid as functional monomer, ethylene glycol maleic rosinate acrylate as a cross linking agent by thermal polymerization method. The optimum experimental conditions were explored.The electrochemical properties of the nano-doped sensor were investigated using cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS). The structure and morphology of the imprinted film were characterized by infrared spectroscopy and scanning electron microscopy. In the optimal conditions, the relative redox peak currents of hexacyanoferrate were linear. The concentration of amobarbital ranged from 6.5×10-8 to 1.8×10-4 mol/L, with a linear correlation coefficient of 0.9986. The detection limit was 1.1×10-9 mol/L(S/N=3). The prepared sensor was applied to the determination of amobarbital in pork samples with recovery ranging from 96.50% to 103.25%.