Vu Trung Hieu, Yu Byung Jo, Kim Moon Il
Department of BioNano Technology, Gachon University, 1342 Seongnamdae-ro, Sujeong-gu, Seongnam 13120, Republic of Korea.
Low-Carbon Transition R&D Department, Research Institute of Sustainable Development Technology, Korea Institute of Industrial Technology (KITECH), Cheonan 31056, Republic of Korea.
Biosensors (Basel). 2024 Nov 21;14(12):563. doi: 10.3390/bios14120563.
Choline is an important molecule in monitoring food safety and infant nutrition. Here, we report Ce nanogels synthesized by atom transfer radical polymerization (ATRP) employing Ce-coordinated acryloyl-lysine polymer brushes (Ce@SiO NGs) as highly efficient cascade nanozymes for colorimetric detection of choline. The synthesized Ce@SiO NGs demonstrated remarkable peroxidase-like activity with a porous exterior, which are essential to entrap choline oxidase (COx) to yield COx@Ce@SiO NGs and construct a cascade reaction system to detect choline. Immobilized COx catalyzed the oxidation of choline in food samples to produce HO, which subsequently induced the oxidation of chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) to produce blue color signals. This method enabled the selective and sensitive detection of target choline with a satisfactory linear range of 4-400 μM, which is sufficient to analyze foodborne choline. The practical utility of the COx@Ce@SiO NG-based assay was successfully validated to determine choline spiked in commercially available milk and infant formula with high accuracy and precision values. This approach provides a simple and affordable method of choline detection and has the potential to lead to more developments in ATRP-based nanozymes for diverse biosensing applications.
胆碱是监测食品安全和婴儿营养的重要分子。在此，我们报道了通过原子转移自由基聚合（ATRP）合成的铈纳米凝胶，该纳米凝胶采用铈配位的丙烯酰赖氨酸聚合物刷（Ce@SiO纳米凝胶）作为高效级联纳米酶用于比色法检测胆碱。合成的Ce@SiO纳米凝胶具有多孔的外部结构，表现出显著的过氧化物酶样活性，这对于捕获胆碱氧化酶（COx）以产生COx@Ce@SiO纳米凝胶并构建用于检测胆碱的级联反应系统至关重要。固定化的COx催化食品样品中胆碱的氧化以产生H₂O₂，随后H₂O₂诱导显色底物3,3',5,5'-四甲基联苯胺（TMB）氧化以产生蓝色信号。该方法能够选择性和灵敏地检测目标胆碱，其令人满意的线性范围为4 - 400 μM，足以分析食源性胆碱。基于COx@Ce@SiO纳米凝胶的检测方法的实际效用已成功验证，可用于高精度和精密度地测定市售牛奶和婴儿配方奶粉中添加的胆碱。这种方法提供了一种简单且经济实惠的胆碱检测方法，并且有可能在基于ATRP的纳米酶用于各种生物传感应用方面带来更多进展。
