Abstract:
This work presents the modification of glassy carbon electrodes (GCE) by using a dispersion resulting from the non-covalent functionalization of multi-walled carbon nanotubes (MWCNT) with polyarginine (polyArg). MWCNT-polyArg is used for the quantification of ascorbic acid (AA) in the presence of acetaminophen (APAP) and viceversa. Since ascorbic acid and acetaminophen are strongly absorbed on GCE/MWCNT-polyArg, they can be detected in the presence of 4.0×10-5 M acetaminophen (and 3.0×10-5 M ascorbic acid) by using adsorptive stripping with media exchange and differential pulse voltammetry. Using water as the solvent for the MWCNT dispersion, the result was Z-potential of 0.053 ± 0.006 V. The developed sensor showed excellent specificity, sensitivity, stability and reproducibility compared to previously published sensors. The GCE/MWCNT-polyArg sensor shows a fast response time of ∼5 minutes, low limits of detection and quantification for AA (0.95 and 2.9 μM respectively) and APAP (0.27 and 0.82μM, respectively), high sensitivity of 0.0616 μA/M for AA or APAP 0.240μA/M. It was used to test its practicability by determining the concentration of AA or APAP (AA and APAP) in pharmaceutical samples. Finally, the simultaneous measurement of ascorbic acid and acetaminophen in pharmaceuticals showed a good correlation, with a maximum error and RSD of 4.5 and 5.1 %, respectively.
摘要:
这项工作提出了通过使用由多壁碳纳米管(MWCNT)与聚精氨酸(polyArg)的非共价官能化产生的分散体来修饰玻碳电极(GCE)。MWCNT-polyArg用于在对乙酰氨基酚(APAP)存在下定量抗坏血酸(AA),反之亦然。由于抗坏血酸和对乙酰氨基酚被GCE/MWCNT-polyArg强烈吸收,它们可以在4.0×10-5M对乙酰氨基酚(和3.0×10-5M抗坏血酸)的存在下通过使用介质交换和差分脉冲伏安法的吸附溶出来检测。使用水作为MWCNT分散体的溶剂,结果是0.053±0.006V的Z电位。开发的传感器显示出优异的特异性,灵敏度,与以前发表的传感器相比,稳定性和再现性。GCE/MWCNT-polyArg传感器具有5分钟的快速响应时间,AA(分别为0.95和2.9μM)和APAP(0.27和0.82μM,分别),对于AA或APAP0.240μA/M,高灵敏度为0.0616μA/M。通过确定药物样品中AA或APAP(AA和APAP)的浓度来测试其实用性。最后,药物中抗坏血酸和对乙酰氨基酚的同时测定显示出良好的相关性,最大误差和RSD分别为4.5和5.1%,分别。