Monitoring of vitamin B₁₂ is important in the quality control of various pharmaceutical products. In this work, we design an ultrasensitive electrochemical sensor for the detection of vitamin B₁₂ employing Pt modified Cu(HBTC)(4,4′-bipy)·3DMF (Pt = Platinum; DMF = N,N′-dimethylformamide; 4,4′-bipy = 4,4′-bipyridine; HBTC = 1,3,5-benzenetricarboxylic acid) electrode as an efficient electrocatalyst. The copper (Cu) complex nanorods were synthesised by solvothermal method and characterised by different surface analytical techniques. Cyclic voltammetric analysis reveals that the modified electrode shows excellent electrocatalytic redox reversibility towards Co³⁺/Co²⁺ redox couple at −0.192 and -0.268 V (vs. Ag/AgCl) with a sensitivity of 0.104 µA µM⁻¹, a low detection limit of 50 nM, a signal-to-noise ratio of 3 and a wide linear range of 0.1–188.2 µM. The novelty of the system is that both oxidation and reduction currents Co³⁺/Co²⁺ redox couple has been used for the calibration curve so that the analytical errors during the course of analysis would be minimised. The enhanced electrocatalytic ability of the material has enabled discrimination of vitamin B₁₂ from potential interfering species. The fabricated electrode was applied for the detection of vitamin B₁₂ in two commercial pharmaceutical tablets and the results were found to be satisfactory.

维生素B _12的监测对各种药品的质量控制很重要。在这项工作中，我们设计了一种用于检测维生素B ₁₂的超灵敏电化学传感器，该传感器采用Pt修饰的Cu（HBTC）（4,4'-bipy）·3DMF（Pt =铂； DMF = N，N'-二甲基甲酰胺; 4， 4'-bipy = 4,4'-bipyridine; HBTC = 1,3,5-苯三甲酸）电极作为有效的电催化剂。通过溶剂热法合成了铜（Cu）复合纳米棒，并通过不同的表面分析技术对其进行了表征。循环伏安分析表明，修饰的电极在-0.192和-0.268 V时对Co ³⁺ / Co ²⁺氧化还原电偶表现出优异的电催化氧化还原可逆性（相对于Ag / AgCl）的灵敏度为0.104 µA µM ^-1，检测限为50 nM，信噪比为3，线性范围为0.1–188.2 µM。该系统的新颖之处在于，氧化电流和还原电流Co ³⁺ / Co ²⁺氧化还原对都已用于校准曲线，从而可将分析过程中的分析误差降至最低。该材料增强的电催化能力使得能够将维生素B ₁₂与潜在的干扰物质区分开。所制备的电极用于两种商业药物片剂中维生素B ₁₂的检测，结果令人满意。