Jia Mingyu, Wang Jueyu, Liu Yuxuan, Cui Daizong, Zhao Min
College of Life Science, Northeast Forestry University, Harbin 150040, China.
Int J Mol Sci. 2024 Nov 21;25(23):12518. doi: 10.3390/ijms252312518.
In this study, Fe(PO)·8HO magnetic nanoparticles (MNPs) were successfully extracted from the strain CG-1. We subsequently characterized their composition, structure, and morphology, revealing that these nanoparticles consisted of Fe(PO)·8HO with an average diameter of 66.87 ± 0.56 nm. Our measurements indicated magnetic parameters of 151 Oe for coercivity, 2 emu/g for saturation remanence, and 16 emu/g for saturation magnetization. Our findings confirmed that these magnetic nanoparticles exhibited intrinsic peroxidase-like activity, catalyzing the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of HO. Compared to horseradish peroxidase (HRP), the peroxidase mimic demonstrated greater stability under various physicochemical conditions. To investigate the mechanisms underlying the peroxidase-like catalysis of Fe(PO)·8HO, we employed fluorescence spectroscopy and electron spin resonance (ESR) analysis. The results revealed that the peroxidase-like activity of Fe(PO)·8HO stemmed from the generation of hydroxyl radicals (·OH). Furthermore, we established a platform for the colorimetric detection of HO and glucose. Our method was capable of detecting HO concentrations as low as 1.0 × 10 mmol/L. Impressively, this sensitive method was successfully applied to determine glucose levels in human serum.
在本研究中，成功从CG - 1菌株中提取出磷酸铁（Fe(PO)·8HO）磁性纳米颗粒（MNPs）。随后我们对其组成、结构和形态进行了表征，发现这些纳米颗粒由平均直径为66.87 ± 0.56 nm的Fe(PO)·8HO组成。我们的测量表明，其矫顽力为151 Oe，饱和剩磁为2 emu/g，饱和磁化强度为16 emu/g。我们的研究结果证实，这些磁性纳米颗粒具有内在的类过氧化物酶活性，在过氧化氢（HO）存在的情况下催化3,3,5,5 - 四甲基联苯胺（TMB）的氧化。与辣根过氧化物酶（HRP）相比，这种过氧化物酶模拟物在各种物理化学条件下表现出更高的稳定性。为了探究Fe(PO)·8HO类过氧化物酶催化的潜在机制，我们采用了荧光光谱和电子自旋共振（ESR）分析。结果表明，Fe(PO)·8HO的类过氧化物酶活性源于羟基自由基（·OH）的产生。此外，我们建立了一个用于比色检测HO和葡萄糖的平台。我们的方法能够检测低至1.0 × 10 mmol/L的HO浓度。令人印象深刻的是，这种灵敏的方法成功应用于测定人血清中的葡萄糖水平。
