韓 慧, 李錦州,孫仁霞
(哈爾濱師范大學 化學化工學院,黑龍江 哈爾濱 150025)
聚吡咯-酰基吡唑啉酮復合膜修飾玻碳電極測定酚磺乙胺的研究*
韓 慧, 李錦州**,孫仁霞
(哈爾濱師范大學 化學化工學院,黑龍江 哈爾濱 150025)
報道了一種新型聚吡咯-酰基吡唑啉酮復合膜修飾玻碳電極(Ppy/HPMαFP/GCE)對酚磺乙胺(ETH)電化學性質及其反應機理的研究。酚磺乙胺的電化學性質檢測運用循環伏安法和脈沖伏安法。實驗表明,與裸GCE和Ppy/GCE相比,Ppy/HPM αFP/GCE修飾電極對酚磺乙胺有良好的催化作用。聚吡咯與酰基吡唑啉酮產生了協同增效作用。在pH=5.5的磷酸鹽(PBS)緩沖溶液中,該修飾電極測試ETH的CV曲線于0.35V和0.4V出現一對靈敏的氧化還原峰,峰電位差△Ep較裸玻碳電極降低510mV,比Ppy修飾電極降低100mV,峰電流顯著增加。在最佳條件下, 氧化峰電流與ETH濃度于2.0×10-6~1.0×10-4mol·L-1范圍內呈現良好的線性關系,檢出限為6.0×10-7mol·L-1。
聚吡咯;酰基吡唑啉酮;酚磺乙胺;修飾電極
Abstract:In this paper,a novel voltammetric method using poly-pyrrole and acyl-pyrazolone composite film modified glassy carbon electrode(Ppy/HPMαFP/GCE)was developed for studying the electrochemical behavior and reaction mechanism of ethamsylate.The electrochemical parameters of ethamsylate were investigated by cyclic voltammetry and differential pulse voltammetry.Compared to the bare GCE and Ppy/GCE,the Ppy/HPMαFP/GCE showed an excellent electro-catalytical effect on the oxidation of ethamsylate with significant increase in the peak current.The above results indicated that a synergistic effect was existed between poly-pyrrole and HPMαFP.According to the experiment,In PBS buffer solution with a pH of 5.5,a pair of sensitive redox peaks with Epa=0.40V,Epc=0.35V(vs.SCE)was obtained on the PPy/HPMαFP modified electrode.The difference of peak potentials(△Ep)was 510mV which was lower than on bare glassy carbon electrode,and about 100mV lower than on Ppy modified electrode.Meanwhile,the peak current markedly increased.Under the optimum conditions,linear calibration curve was obtained in the concentration range of 2.0×10-6~1.0×10-4mol·L-1.The detection limit was 6.0×10-7mol·L-1.Key words:Poly-pyrrole;acyl-pyrazolone;ethamsylate;modified electrode
1.1 儀器與試劑
電化學測試實驗均在CHI 650A電化學工作站(上海辰華儀器公司,上海)上完成。采用三電極系統:飽和甘汞電極(SCE)為參比電極、鉑電極為對電極、酰基吡唑啉酮 /聚吡咯修飾電極(HPMαFP/Ppy/GCE)(d=4mm)為工作電極。所有電位均相對于飽和甘汞電極。
吡咯(pyrrole簡寫py,國藥集團化學試劑有限公司);HPMαFP按文獻[12]方法合成,以無水乙醇為溶劑配成濃度為1.0×10-2mol·L-1的溶液,備用;酚磺乙胺 (天津市大茂化學試劑廠)溶于水配制成1.0×10-3mol·L-1的標準溶液,用時稀釋至所需濃度;磷酸鹽緩沖溶液為 0.1 mol·L-1NaH2PO4和Na2HPO4兩種溶液混合而成。其它試劑均為分析純,實驗用水為二次蒸餾水。……