将多壁碳纳米管(MWNT)分散在疏水性表面活性剂双十六烷基磷酸(DHP)溶液中形成稳定、均相的分散液,然后制备多壁碳纳米管-DHP复合膜修饰玻碳电极(MWNT-DHP/GCE).应用方波伏安法研究了沙丁胺醇在修饰电极上的电化学行为,结果表明,碳纳米管复合膜修饰电极对沙丁胺醇的氧化有良好的电催化活性,其氧化反应为一电子一质子过程,氧化电位比裸玻碳电极负移40 mV,峰电流增加了4.5倍.在最佳测试条件下,氧化峰电流与沙丁胺醇浓度在8.3×10-7~3.3×10-6mol/L范围内呈良好线性关系,开路富集2min,检出限达1.8×10-7mol/L.该修饰电极具有良好的重现性、稳定性.
The multi-wall carbon nanotubes(MWNT) were dispersed successfully into water in the presence of dihexadecyl hydrogen phosphate(DHP) and a stable well-distributed suspension.A was formed sensor based on the multi-carbon nanotubes film coated glassy carbon electrode was developed.The electrochemical response of salbutamol was studied by square wave voltammetry.The oxidation peak potential of salbutamol at the modified electrode was observed at 0.604 V,which shifted about 40 mV negatively.The peak current increased 4.5 folds,in contrast to that at a bare electrode.Under optimal measurement conditions,there was a good linear relationship between the peak current(Ipa) and salbutamol concentration(C) in the range from 8.3 × 1 0-7~ 3.3 ×10-6 mol/L,and a detection limit of 1.8× 1 0-7 mol/L(S/N=3) was achieved after 2 min of open-circuit accumulation.The performance of this sensor was excelled in the reproducibility and stability.The electro-oxidation of salbutamol was a one-electron and one-proton irreversible process,and the probable electrode reaction was proposed.
[1]Qin Yong-ping(秦永平),Zou Yuan-gao(邹远高),Liang Mao-zhi(梁茂植),et al.Determination of sabu-tamol in human plasma by reversed phase HPLC withUV detection[J].Chinese Pharmaceutical Journal(inChinese),2000,7:475.
[2]Cleber Antonio Lindino,Lu姫s Ot偄vio S Bulh es.Deter-mination of fenoterol and salbutamol in pharmaceuticalformulations by electrogenerated chemiluminescence[J].Talanta,2007,72:1746.
[3]Dave H N,Mashru R C,Thakkar A R.Simultaneousdetermination of salbutamol sulphate,bromhexinehydrochloride and etofylline in pharmaceutical formula-tions with the use of four rapid derivative spectrophoto-metric methods[J].Analytica Chimica Acta,2007,597:113.
[4]AjayanPM,Zhou OZ.Carbon nanotubes[J].TopAppl Phys,2001,80:391.
[5]Zhu Yuan-Hai(朱远海),Zhang Zhi-Ling(张治凌),Pang Dai-Wen(庞代文).Electrochemical oxidation oftheophylline at multi-wall carbon nanotube modifiedglassy carbon electrodes[J].J Electroanal Chem,2005,581:303.
[6]Wu Kangbing(吴康兵),Wang Hong(王红),ChenFang(陈芳),et al.Electrochemistry and voltammetryof procaine using a carbon nanotube film coated elec-trode[J].Bioelectrochemistry,2006,68:144.
[7]Britto P J,Santhanam KS V,Rubio A,et al.Improvedcharge transfer at carbon nanotube electrodes[J].AdvMater,1999,11:107.
[8]Song Yuan-zhi(宋远致).Theoretical studyon theelectrochemical behavior of norepinephrine at Nafionmulti-walled carbon nanotubes modified pyrolytic graph-ite electrode[J].Spectrochimica Acta Part A:Molecu-lar and Biomolecular Spectroscopy,2007,67:1169.
[9]Zhao Guang-Chao(赵广超),Yin Zheng-Zhi(尹政志),Zhang Li(张立),et al.Direct electrochemistryof cytochrome-c on a multi-walled carbon nanotubesmodified electrode and its electrocatalytic activity for thereduction of H2O2[J].Electrochemistry Communica-tions,2005,7:256.
[10]Saeed Shahrokhian,Hamid Reza,Zare-Mehrjardi.Application of thionine-nafion supported on multi-walled carbon nanotube for preparation of a modified e-lectrode in simultaneous voltammetric detection of do-pamine and ascorbic acid[J].Electrochimica Acta,2007,52:6310.
[11]Tsang S C,Chen Y K,Harris P J E,et al.A simplechemical method of opening and filling carbon nano-tubes[J].Nature,1994,372:159.
[12]Santucci R,PicciauCampanella L,Brunori M.Elec-trochemistry of metalloproteins[J].Curr Top Electro-chem A,1994,3:313.
[13]Dillon A C,Jones K M,Bekkedahl T A,et al.Stor-age of hydrogen in single-walled carbon nanotubes[J].Nature,1997,386:377.
