A highly selective and rapid anodic adsorptive voltammetric method was developed for the （determination） of ultra trace amount of ofloxacin at a carbon paste electrode（CPE）. The ofloxacin adsorbed on the surface o...A highly selective and rapid anodic adsorptive voltammetric method was developed for the （determination） of ultra trace amount of ofloxacin at a carbon paste electrode（CPE）. The ofloxacin adsorbed on the surface of the CPE in a 0.096 mol/L KHP-NaOH buffer solution（pH=5.6） could produce one oxidation peak at 0.92 V（vs.SCE） when scanning was performed from 0.4 to 1.4 V. The relationship between the peak current and the ofloxacin concentration was linear in the ranges of 5.5×10-9～5.5×10-8 mol/L（75 s accumulation） and 3.3×10-8～3.3×10-7 mol/L（30 s accumulation）. The correlation coefficients were 0.996 and 0.998, respectively. Its detection limit was 9.0×10-10 mol/L（S/N=3） for 150 s accumulation. The （electrode） reaction mechanism of ofloxacin was investigated. The proposed method was applied to analyze trace ofloxacin in urine samples. The result was in good agreement with that obtained by spectrophotometry （determination）.展开更多
A highly selective and rapid new anodic adsorptive voltammetric method was developed for the determination of ultra trace amount of pipemidic acid at a carbon paste electrode（CPE）.The pipemidic acid is adsorbed on t...A highly selective and rapid new anodic adsorptive voltammetric method was developed for the determination of ultra trace amount of pipemidic acid at a carbon paste electrode（CPE）.The pipemidic acid is adsorbed on the surface of the CPE in 0.64mol·L-1NH4Ac-HAc buffer solution（pH4.90）and yields one oxidation peak at 1.05V（vs.SCE）when nearly scanning from 0.8 to 1.8V.The relationship between the peak current and pipemidic acid concentration is linear in the range of 2.0×10-9to 2.0×10-7mol·L-1with the correlation coefficient 0.995.Its detection limit is 6.0×10-10mol·L-1（S/N=3）for 150s accumulation.The proposed method was applied to determine the trace of pipemidic acid in the urine samples.展开更多
A carbon paste electrode modified with multi-walled carbon nanotubes (MWCNT) was prepared and the determination of ultra trace amount of zirconium based on the anodic adsorptive voltammetry of the zirconium-calcium-al...A carbon paste electrode modified with multi-walled carbon nanotubes (MWCNT) was prepared and the determination of ultra trace amount of zirconium based on the anodic adsorptive voltammetry of the zirconium-calcium-alizarin red S mix-polynuclear complex is described in this paper for the first time. The results showed that the sensitivity and the selectivity of the method are excellent. The second de-rivative linear scan voltammograms of the complex were recorded by polarographic analyzer from 200 to 1200 mV (vs. SCE) and it was found that the complex can be adsorbed on the surface of the electrode, yielding a peak at about 840 mV, corresponding to the oxidation of ARS in the complex. The peak cur-rent increases linearly with Zr (IV) concentration in the range of 6.0×10-12―6.0×10-11 mol·L-1 (accumu-lation time 120 s), 6.0×10-11―2.0×10-9 mol·L-1 (accumulation time 90 s) and 2.0×10-9―1.0×10-7 mol·L-1 (accumulation time 60 s) and the detection limit (S/N = 3) is 2.0×10-12 mol·L-1 (accumulation time 180 s). The procedure has been successfully applied to the determination of zirconium in the ore samples.展开更多
文摘A highly selective and rapid anodic adsorptive voltammetric method was developed for the （determination） of ultra trace amount of ofloxacin at a carbon paste electrode（CPE）. The ofloxacin adsorbed on the surface of the CPE in a 0.096 mol/L KHP-NaOH buffer solution（pH=5.6） could produce one oxidation peak at 0.92 V（vs.SCE） when scanning was performed from 0.4 to 1.4 V. The relationship between the peak current and the ofloxacin concentration was linear in the ranges of 5.5×10-9～5.5×10-8 mol/L（75 s accumulation） and 3.3×10-8～3.3×10-7 mol/L（30 s accumulation）. The correlation coefficients were 0.996 and 0.998, respectively. Its detection limit was 9.0×10-10 mol/L（S/N=3） for 150 s accumulation. The （electrode） reaction mechanism of ofloxacin was investigated. The proposed method was applied to analyze trace ofloxacin in urine samples. The result was in good agreement with that obtained by spectrophotometry （determination）.
文摘A highly selective and rapid new anodic adsorptive voltammetric method was developed for the determination of ultra trace amount of pipemidic acid at a carbon paste electrode（CPE）.The pipemidic acid is adsorbed on the surface of the CPE in 0.64mol·L-1NH4Ac-HAc buffer solution（pH4.90）and yields one oxidation peak at 1.05V（vs.SCE）when nearly scanning from 0.8 to 1.8V.The relationship between the peak current and pipemidic acid concentration is linear in the range of 2.0×10-9to 2.0×10-7mol·L-1with the correlation coefficient 0.995.Its detection limit is 6.0×10-10mol·L-1（S/N=3）for 150s accumulation.The proposed method was applied to determine the trace of pipemidic acid in the urine samples.
基金the Project of Science and Technology Fund of Hengyang City (Grant No. 2007KJ001)the Project of Scientific Research of Hengyang Normal University (Grant No. 07A19)+1 种基金the Key Project of Chinese Ministry of Education (Grant No. 206104)the Multidiscipline Scientific Research Foundation of Xiangtan Univer-sity (Grant No. 05IND08)
文摘A carbon paste electrode modified with multi-walled carbon nanotubes (MWCNT) was prepared and the determination of ultra trace amount of zirconium based on the anodic adsorptive voltammetry of the zirconium-calcium-alizarin red S mix-polynuclear complex is described in this paper for the first time. The results showed that the sensitivity and the selectivity of the method are excellent. The second de-rivative linear scan voltammograms of the complex were recorded by polarographic analyzer from 200 to 1200 mV (vs. SCE) and it was found that the complex can be adsorbed on the surface of the electrode, yielding a peak at about 840 mV, corresponding to the oxidation of ARS in the complex. The peak cur-rent increases linearly with Zr (IV) concentration in the range of 6.0×10-12―6.0×10-11 mol·L-1 (accumu-lation time 120 s), 6.0×10-11―2.0×10-9 mol·L-1 (accumulation time 90 s) and 2.0×10-9―1.0×10-7 mol·L-1 (accumulation time 60 s) and the detection limit (S/N = 3) is 2.0×10-12 mol·L-1 (accumulation time 180 s). The procedure has been successfully applied to the determination of zirconium in the ore samples.
