木质素碳纳米酶的制备及用于检测人尿液中多巴胺

Preparation of lignin carbon nanoenzyme and its detection for dopamine in human urine

以木质素磺酸钠为碳源,水热法合成了MoS2掺杂的碳纳米酶(Mo,S-CDs),并基于其过氧化物酶特性,将其用于检测人尿中多巴胺的含量。对纳米酶的形貌进行了表征。结果显示,Mo,S-CDs为球型,直径在2 nm左右,在水中能够较好的分散;红外图谱结果表明Mo,S-CDs表面官能团丰富;X射线光电子能谱表明Mo,S-CDs中存在Mo,S,C,O元素。Mo,S-CDs具有稳定、高效的过氧化物酶催化活性,可催化H_(2)O_(2)与3,3’,5,5’-四甲基联苯胺(TMB)反应,生成氧化产物oxTMB。蓝色的oxTMB可被多巴胺还原回TMB,导致系统在oxTMB特征峰处的吸光度下降。因此,基于Mo,S-CDs对H_(2)O_(2)的传感能力构建了多巴胺-Mo,S-CDs的催化传感体系,并用于检测人尿液中多巴胺的含量。多巴胺浓度在0.5-20μmol/L范围内有良好的线性关系,检出限为0.0639μmol/L,回收率为96.5%~101.7%,相对标准偏差(RSD)<5%。

This study focuses on the issue of papaya seed adulteration in black pepper, utilizing it as a representative case for research. A novel method that combines molecular amplification with lateral flow chromatography(LFA) has been developed. By merging recombinase polymerase chain reaction(RPA) and LFA technologies, a highly sensitive and rapid detection of papaya seed adulteration in black pepper samples was successfully achieved. The limit of detection(LOD) of this method was 0.1%, and the entire detection process can be completed within 40 min. This method is suitable for on-site testing and has been proven to be effective in authenticating the purity of black pepper spices.