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[Display omitted] • The terminology of bionanozyme was conceptualized. • Three Zn-heptapeptide bionanozymes with nanofibrous architecture were assembled. • Zn-heptapeptide bionanozymes exhibited favorable hydrolase-like activity towards p -nitrophenyl esters. • Zn-heptapeptide bionanozymes were applied for degradation of di(2-ethylhexyl) phthalate (DEHP). Nanozyme with intrinsic enzyme-like activity has emerged as favorite artificial catalyst during recent years. However, current nanozymes are mainly limited to inorganic-derived nanomaterials, while biomolecule-sourced nanozyme (bionanozyme) are rarely reported. Herein, inspired by the basic structure of natural hydrolase family, we constructed 3 oligopeptide-based bionanozymes with intrinsic hydrolase-like activity by implementing zinc induced self-assembly of histidine-rich heptapeptides. Under mild condition, divalent zinc (Zn2+) impelled the spontaneous assembly of short peptides (i.e. Ac-IHIHIQI-CONH 2 , Ac-IHIHIYI-CONH 2 , and Ac-IHVHLQI-CONH 2), forming hydrolase-mimicking bionanozymes with β -sheet secondary conformation and nanofibrous architecture. As expected, the resultant bionanozymes were able to hydrolyze a serious of p -nitrophenyl esters, including not only the simple substrate with short side-chain (p -NPA), but also more complicated ones (p -NPB, p -NPH, p -NPO, and p -NPS). Moreover, the self-assembled Zn-heptapeptide bionanozymes were also proven to be capable of degrading di(2-ethylhexyl) phthalate (DEHP), a typical plasticizer, showing great potential for environmental remediation. Based on this study, we aim to provide theoretical references and exemplify a specific case for directing the construction and application of bionanozyme. [ABSTRACT FROM AUTHOR]

Abstract: Micro-patterned films obtained from micro-contact printing (μCP) method are often challenged by site selectivity limitation. For applications site-selectivity requires improvements. In this paper a site-selective deposition of the rutile TiO2 thin films on patterned SnO2 film, which was formed on the patterned octadecyltrichlorosilane (OTS) SAMs through μCP is described. The depositions proceeded in an environmentally friendly aqueous solution (SnCl4 and peroxotitanium acidic solution) at a lower temperature (80 °C). It is shown that the OTS SAMs has a good selectivity deposition for SnO2 particles, which was mainly dominated by the heterogeneous nucleation mechanism. The SnO2 layer had a structure-directing effect for growth of the rutile TiO2, which was usually formed above 600 °C. The patterned films were characterized by a variety of techniques, including ellipsometry, optical microscopy, SEM, AFM, XPS, and DLS to determine the thicknesses, topologies, microstructures, chemical compositions of the films, particle sizes and zeta potentials of the titanium particles. [Copyright &y& Elsevier]

[Display omitted] In view of the current public health hazards of food-borne pathogens, it is urgent to develop a rapid detection method with high sensitivity, good specificity and operational convenience, as well as to determine an effective sterilization strategy. Herein, versatile gold-ruthenium nanocomposites modified with antibody (Au@Ru-pAb Ncs) have been constructed for the sensitive detection of Salmonella typhimurium (S. typhimurium) via the lateral flow immunochromatographic assay (LFIA). Au@Ru-pAb Ncs based LFIA exhibited a wide detection range from 2.9 × 106 CFU/mL to 2.9 × 1011 CFU/mL with the limit of detection of 9.8 × 104 CFU/mL for S. typhimurium, and displayed excellent specificity. In addition, Au@Ru-pAb Ncs irradiated with 808 nm (500 mW/cm2) near-infrared light (NIR) had a significant antibacterial effect within only 5 min, attributed to its high photothermal conversion efficiency of 54.14%. Therefore, both sensitive detection of S. typhimurium and effective NIR-triggered photothermal sterilization were achieved by using versatile Au@Ru-pAb Ncs, showing great prospects in the field of pathogen detection and treatment. [ABSTRACT FROM AUTHOR]

Abstract: The article reports on a very simple method to fabricate superhydrophobic surfaces with Cu–Zn alloy via changing the local oxygen concentration and formation of oxygen difference cell, which can be readily realized by covering or contacting the Cu–Zn alloy surface with a glass slide. This superhydrophobic film comes from the formation of a flower-like hierarchical structure due to the accelerated alloy etching. In contrast, the white film grown in the un-covered area showed a much lower hydrophobicity due to its different morphology. These superhydrophobic surfaces or superhydrophobic–hydrophobic surfaces are expected to find applications in making self-cleaning alloy surface, in metal anticorrosion, and in biomineralization, etc. [Copyright &y& Elsevier]