National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103, Donat Street, 400293 Cluj-Napoca, Romania.
Laboratory of Electrochemistry and PATLAB, National Institute of Research for Electrochemistry and Condensed Matter, 202 Splaiul Independentei Str., 060021 Bucharest, Romania.
Sensors (Basel). 2022 Aug 18;22(16):6181. doi: 10.3390/s22166181.
An electrochemical cell containing two graphite rods was filled with the appropriate electrolyte (0.2 M ammonia + 0.2 M ammonium sulphate) and connected to the exfoliation system to synthesize graphene (EGr). A bias of 7 V was applied between the anode and cathode for 3 h. After synthesis, the morphology and structure of the sample was characterized by SEM, XRD, and FTIR techniques. The material was deposited onto the surface of a glassy carbon (GC) electrode (EGr/GC) and employed for the electrochemical detection of azithromycin (AZT). The DPV signals recorded in pH 5 acetate containing 6 × 10 M AZT revealed significant differences between the GC and EGr/GC electrodes. For EGr/GC, the oxidation peak was higher and appeared at lower potential (+1.12 V) compared with that of bare GC (+1.35 V). The linear range for AZT obtained with the EGr/GC electrode was very wide, 10-10 M, the sensitivity was 0.68 A/M, and the detection limit was 3.03 × 10 M. It is important to mention that the sensitivity of EGr/GC was three times higher than that of bare GC (0.23 A/M), proving the advantages of using graphene-modified electrodes in the electrochemical detection of AZT.
电化学电池中装有两根石墨棒，充满了适当的电解质（0.2 M 氨+0.2 M 硫酸铵），并与剥离系统连接，以合成石墨烯（EGr）。在阳极和阴极之间施加 7 V 的偏压，持续 3 小时。合成后，通过 SEM、XRD 和 FTIR 技术对样品的形貌和结构进行了表征。将该材料沉积在玻璃碳（GC）电极表面（EGr/GC）上，并用于阿奇霉素（AZT）的电化学检测。在含有 6×10 M AZT 的 pH 5 乙酸盐中记录的 DPV 信号显示 GC 和 EGr/GC 电极之间存在显著差异。对于 EGr/GC，氧化峰更高，出现在比裸 GC 更低的电位（+1.12 V）（+1.35 V）。用 EGr/GC 电极获得的 AZT 的线性范围非常宽，为 10-10 M，灵敏度为 0.68 A/M，检测限为 3.03×10 M。值得一提的是，EGr/GC 的灵敏度比裸 GC 高三倍（0.23 A/M），证明了在 AZT 的电化学检测中使用石墨烯修饰电极的优势。
