title: Peroxidase-like activity of mesoporous silica encapsulated Pt nanoparticle and its application in colorimetric immunoassay.
abstract: Nanomaterial-based artificial enzymes have received great attention in recent year due to their potential application in immunoassay techniques. However, such potential is usually limited by poor dispersion stability or low catalytic activity induced by the capping agent essentially required in the synthesis. In an attempt to address these challenges, here, we studied the novel Pt nanoparticles (NPs) based peroxidase-like mimic by encapsulating Pt NP in mesoporous silica (Pt@mSiO2 NPs). Compared with other nanomaterial-based artificial enzymes, the obtained Pt@mSiO2 NPs not only exhibit high peroxidase-like activity but also have good dispersion stability in buffer saline solution when grafted with spacer PEG. Results show that when the thickness of silica shell is about 9 nm the resulting Pt@mSiO2 NPs exhibit the catalytic activity similar to that of Pt NPs, which is approximately 26 times higher than that of Fe3O4 NPs (in terms of Kcat for H2O2). Due to the protection of silica shell, the subsequent surface modification with antibody has little effect on their catalytic activity. The analytical performance of this system in detecting hCG shows that after 5 min incubation the limit of detection can reach 10 ng mL(-1) and dynamic linear working range is 5-200 ng mL(-1). Our findings pave the way for design and development of novel artificial enzyme labeling.
authors: School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China. Electronic address: zfwang@seu.edu.cn.
authors: Zhifei
authors: Z
authors: Wang
authors: School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China.
authors: Xia
authors: X
authors: Yang
authors: School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China.
authors: Jingjing
authors: J
authors: Yang
authors: School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China.
authors: Yanyun
authors: Y
authors: Jiang
authors: School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China. Electronic address: nyhe1958@163.com.
authors: Nongyue
authors: N
authors: He
mesh_terms: D006063:Chorionic Gonadotropin / Q000032:analysis* / Q000378:metabolism; D003124:Colorimetry / Q000379:methods*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry*; D015394:Molecular Structure; D010316:Particle Size; D009195:Peroxidase / Q000737:chemistry / Q000378:metabolism*; D010984:Platinum / Q000737:chemistry*; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D006063:Chorionic Gonadotropin; D010984:Platinum; D012822:Silicon Dioxide; D009195:Peroxidase
keywords: Colorimetric immunoassay; Core–shell structure; Mesoporous silica; Peroxidase-like mimic; Pt nanoparticle; Signal amplification