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Abstract Noble‐metal nanostructures have emerged as a category of efficient and versatile peroxidase mimics in recent years. Enhancing their peroxidase‐like activities is essential to the realization of certain applications. In this review, we focus on how to engineer noble‐metal nanostructures with enhanced peroxidase‐like activities. The article is organized by introducing the impacts of surface capping ligands, particle size, shape, elemental composition, and internal structure as key parameters for the peroxidase‐like activity of noble‐metal nanostructures. Emphasis is given to the controlled synthesis of nanostructures and their peroxidase‐like catalytic efficiencies. At the end, we provide a perspective on future developments in the research relevant to peroxidase mimics of noble metals.
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Liposome‐Templated Green Synthesis of Mesoporous Metal Nanostructures with Universal Composition for Biomedical Application
Abstract Porous noble metal nanoparticles have received particular attention recently for their unique optical, thermal, and catalytic functions in biomedicine. However, limited progress has been made to synthesize such porous metallic nanostructures with large mesopores (≥25 nm). Here, a green yet facile synthesis strategy using biocompatible liposomes as templates to mediate the formation of mesoporous metallic nanostructures in a controllable fashion is reported. Various monodispersed nanostructures with well‐defined mesoporous shape and large mesopores (≈ 40 nm) are successfully synthesized from mono‐ (Au, Pd, and Pt), bi‐ (AuPd, AuPt, AuRh, PtRh, and PdPt), and tri‐noble metals (AuPdRh, AuPtRh, and AuPdPt). Along with a successful demonstration of its effectiveness in synthesis of various mesoporous nanostructures, the possible mechanism of liposome‐guided formation of such nanostructures via time sectioning of the synthesis process (monitoring time‐resolved growth of mesoporous structures) and computational quantum molecular modeling (analyzing chemical interaction energy between metallic cations and liposomes at the enthalpy level) is also revealed. These mesoporous metallic nanostructures exhibit a strong photothermal effect in the near‐infrared region, effective catalytic activities in hydrogen peroxide decomposition reaction, and high drug loading capacity. Thus, the liposome‐templated method provides an inspiring and robust avenue to synthesize mesoporous noble metal‐based nanostructures for versatile biomedical applications.
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- PAR ID:
- 10441998
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 19
- Issue:
- 46
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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