Tashkhourian J, Nami-Ana S F
Department of Chemistry, College of Sciences, Shiraz University, Shiraz 71454, Iran.
Department of Chemistry, Faculty of Sciences, Persian Gulf University, Bushehr 75169, Iran.
Mater Sci Eng C Mater Biol Appl. 2015;52:103-10. doi: 10.1016/j.msec.2015.03.017. Epub 2015 Mar 14.
Gallic acid (GA), one of the main phenolic components, has been a subject of increasing interest due to their biological properties, including anti-inflammatory, antihistaminic, and antitumor activities, scavenging of free radicals, and protecting against cardiovascular diseases. Therefore, developing sensitive and selective sensor for GA is very important and interesting. Herein, SiO2 nanoparticles were synthesized and then used to prepare a modified carbon paste electrode (CPE) for determination of GA. For better comparison, multiwalled carbon nanotubes (MWCNTs) and graphite were also employed to prepare an electrochemical sensor for determination of GA. The electrochemical behaviors of GA at different electrochemical sensors were investigated. Compared with other sensors, the SiO2 nanoparticle sensor greatly enhances the response signal of GA due to the large active surface area and high accumulation efficiency. Voltammetric studies show that the SiO2 nanoparticle modified carbon paste electrode is sensitive to GA in the concentration range of 8.0 × 10(-7) to 1.0 × 10(-4) mol L(-1), and the limit of detection and sensitivity were calculated as 2.5 × 10(-7) mol L(-1) and 1790.7 (μA/mM), respectively. Finally, the proposed electrochemical sensor was successfully employed to determine GA in tea and orange juice samples.
没食子酸（GA）是主要的酚类成分之一，因其生物特性，包括抗炎、抗组胺和抗肿瘤活性、清除自由基以及预防心血管疾病等，而越来越受到关注。因此，开发用于检测GA的灵敏且选择性高的传感器非常重要且有趣。在此，合成了二氧化硅纳米颗粒，然后将其用于制备用于测定GA的修饰碳糊电极（CPE）。为了进行更好的比较，还使用多壁碳纳米管（MWCNTs）和石墨制备了用于测定GA的电化学传感器。研究了GA在不同电化学传感器上的电化学行为。与其他传感器相比，二氧化硅纳米颗粒传感器由于具有大的活性表面积和高的富集效率，大大增强了GA的响应信号。伏安法研究表明，二氧化硅纳米颗粒修饰的碳糊电极在8.0×10⁻⁷至1.0×10⁻⁴ mol L⁻¹的浓度范围内对GA敏感，检测限和灵敏度分别计算为2.5×10⁻⁷ mol L⁻¹和1790.7（μA/mM）。最后，所提出的电化学传感器成功用于测定茶叶和橙汁样品中的GA。
