羟自由基(·OH)清除能力(HOSC)的估算对于评估抗氧化剂至关重要,天然提取物,或针对临床疾病的药物。虽然纳米酶在相关应用中具有优势,它们仍然面临着活性和选择性的限制。作为回应,这项工作展示了制造的海带蛋白调制的锇(laminarin-Os)纳米簇(1.45±0.05nm),在为合理的HOSC估计量身定制的比色测定中充当过氧化物酶样纳米酶。这项研究验证了海带多糖的表征和显着的稳定性。通过利用海带蛋白Os丰富的表面负电荷和海带蛋白的表面羟基,促进氧化反应,增强laminarin-Os对3,3'的亲和力,5,5'-四甲基联苯胺(TMB)(KM=0.04mM)。这使得基于海带蛋白-Os的比色测定能够比柠檬酸盐更有效地响应·OH,白蛋白-,或其他基于多糖的Os。此外,实验结果还验证了在酸性条件下海带蛋白-Os的选择性过氧化物酶样行为。像抗坏血酸这样的抗氧化剂,谷胱甘肽,鞣酸,和半胱氨酸在比色平台中抑制652nm处的吸光度,使用海带蛋白-Os的过氧化物酶样活性。与商用套件相比,该测定显示出较高的灵敏度(例如,响应抗坏血酸0.01-0.075mM,谷胱甘肽1-15µg/mL,单宁酸0.5-5µM,和甘草酸单铵半胱氨酸1.06-10.63µM)和谷胱甘肽的HOSC测试,鞣酸,和甘草酸单铵半胱氨酸。总的来说,这项研究介绍了一种具有特殊的TMB亲和力和·OH选择性的新型Os纳米酶,为生物医学研究中的HOSC估计铺平了道路,药物分析,药品质量控制,和超越。
Hydroxyl radical (·OH) scavenging capacity (HOSC) estimation is essential for evaluating antioxidants, natural extracts, or drugs against clinical diseases. While nanozymes offer advantages in related applications, they still face limitations in activity and selectivity. In response, this work showcases the fabrication of laminarin-modulated osmium (laminarin-Os) nanoclusters (1.45 ± 0.05 nm), functioning as peroxidase-like nanozymes within a colorimetric assay tailored for rational HOSC estimation. This study validates both the characterization and remarkable stability of laminarin-Os. By leveraging the abundant surface negative charges of laminarin-Os and the surface hydroxyls of laminarin, oxidation reactions are facilitated, augmenting laminarin-Os\'s affinity for 3,3\',5,5\'-tetramethylbenzidine (TMB) (KM = 0.04 mM). This enables the laminarin-Os-based colorimetric assay to respond to ·OH more effectively than citrate-, albumin-, or other polysaccharides-based Os. In addition, experimental results also validate the selective peroxidase-like behavior of laminarin-Os under acidic conditions. Antioxidants like ascorbic acid, glutathione, tannic acid, and cysteine inhibit absorbance at 652 nm in the colorimetric platform using laminarin-Os\'s peroxidase-like activity. Compared with commercial kits, this assay demonstrates superior sensitivity (e.g., responds to ascorbic acid 0.01-0.075 mM, glutathione 1-15 µg/mL, tannic acid 0.5-5 µM, and monoammonium glycyrrhizinate cysteine 1.06-10.63 µM) and HOSC testing for glutathione, tannic acid, and monoammonium glycyrrhizinate cysteine. Overall, this study introduces a novel Os nanozyme with exceptional TMB affinity and ·OH selectivity, paving the way for HOSC estimation in biomedical research, pharmaceutical analysis, drug quality control, and beyond.