Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China.
Analyst. 2012 Oct 7;137(19):4552-8. doi: 10.1039/c2an35700c.
Inorganic nanomaterials that mimic enzymes are fascinating as they potentially have improved properties relative to native enzymes, such as greater resistance to extremes of pH and temperature and lower sensitivity to proteases. Although many artificial enzymes have been investigated, searching for highly-efficient and stable catalysts is still of great interest. In this paper, we first demonstrated that bovine serum albumin (BSA)-stabilized MnO(2) nanoparticles (NPs) exhibited highly peroxidase-, oxidase-, and catalase-like activities. The activities of the BSA-MnO(2) NPs were evaluated using the typical horseradish peroxidase (HRP) substrates o-phenylenediamine (OPD) and 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of either hydrogen peroxide or dissolved oxygen. These small-sized BSA-MnO(2) NPs with good dispersion, solubility and biocompatibility exhibited typical Michaelis-Menten kinetics and high affinity for H(2)O(2), OPD and TMB, indicating that BSA-MnO(2) NPs can be used as satisfactory enzyme mimics. Based on these findings, BSA-MnO(2) NPs were used as colorimetric immunoassay tags for the detection of goat anti-human IgG in place of HRP. The colorimetric immunoassay using BSA-MnO(2) NPs has the advantages of being fast, robust, inexpensive, easily prepared and with no HRP and H(2)O(2) being needed. These water-soluble BSA-MnO(2) NPs may have promising potential applications in biotechnology, bioassays, and biomedicine.
模拟酶的无机纳米材料很有吸引力，因为它们相对于天然酶具有潜在的改善性质，例如更高的酸碱和温度稳定性以及对蛋白酶的更低敏感性。尽管已经研究了许多人工酶，但寻找高效稳定的催化剂仍然具有很大的兴趣。在本文中，我们首先证明牛血清白蛋白（BSA）稳定的 MnO2 纳米粒子（NPs）表现出高度的过氧化物酶、氧化酶和过氧化氢酶样活性。BSA-MnO2 NPs 的活性使用典型的辣根过氧化物酶（HRP）底物邻苯二胺（OPD）和 3,3',5,5'-四甲基联苯胺（TMB）在存在过氧化氢或溶解氧的情况下进行评估。这些具有良好分散性、溶解性和生物相容性的小尺寸 BSA-MnO2 NPs 表现出典型的米氏动力学和对 H2O2、OPD 和 TMB 的高亲和力，表明 BSA-MnO2 NPs 可用作令人满意的酶模拟物。基于这些发现，BSA-MnO2 NPs 被用作比色免疫测定标记物，以替代 HRP 检测山羊抗人 IgG。使用 BSA-MnO2 NPs 的比色免疫测定具有快速、稳健、廉价、易于制备以及不需要 HRP 和 H2O2 的优点。这些水溶性 BSA-MnO2 NPs 在生物技术、生物测定和生物医学方面可能具有广阔的应用前景。
