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Nature has the ingenious capability to design spiky topological features at the macro-and nanoscales, which exhibits fascinating interface adhesive properties by means of multivalent interactions. Following a biomimetic approach, such as nanoscale virus particles are highly infectious toward host cells, a range of organic and inorganic spiky particles (virus-like nanostructures) have been precisely engineered for diverse biomedical applications. Generally, organic virus-like particles (VLPs) derived from viral capsids (often termed as virosomes) have been extensively studied and reviewed, but concomitant concerns regarding immunogenicity and risks of mutagenesis limit clinical potential of organic VLPs. In contrast, inorganic VLPs (viral-mimicking topography) possess fascinating physicochemical characteristics, such as excellent electrical, optical, magnetic, mechanical and catalytic properties, which make them particularly suitable for biomedical applications. Alternatively, there is no comprehensive review related to inorganic VLPs engineered with non-viral shell for biomedical applications. Hence, in this review, we present a brief overview on inorganic VLPs, followed by summarizing the construction and properties of virus-like nanostructures, as well as the mechanisms of nano-bio interface interactions initiated by spiky topography. Furthermore, we focus on the recent advances of VLPs for biomedical applications (including biosensing, antibacterial therapy and cancer treatment). Finally, the future outlook and emerging challenges will be presented. This review aims to provide future scope of the rational design of inorganic non-viral vectors, especially with respect to gene-based therapy platforms.

CO2 fracturing is known as the best solution to improve the efficiency of the CO2 replacement of natural gas hydrates, but the effect of CO2 thickeners on CH4-CO2 replacement are barely noticed. In this work, the effect of four kinds of CO2 thickener—including DL-Lactic acid, polyvinyl acetate, ethyl trifluoroacetate and octamethyl trisiloxane—on the CH4-CO2 replacement in quartz sand was measured thermodynamically and kinetically. The results show that the majority of the CO2 thickeners had no effect on the equilibria of the CH4 and CO2 hydrates, except for DL-Lactic acid, where the temperature depression caused by the addition of 5.5 wt% DL-Lactic acid was about 0.52 and 0.48 K for the CH4 and CO2 hydrates, respectively. In the kinetic measurements, the CH4-CO2 replacement was promoted via the addition of the CO2 thickeners, except DL-Lactic acid. The CO2 thickeners were suggested to strengthen the CH4-CO2 replacement by enhancing the gas exchange in the pore space. Octamethyl trisiloxane, which could promote CH4 recovery and CO2 capture at a low concentration, was suggested to be an ideal CO2 thickener for CH4-CO2 replacement.