Hangyu Zhou

Hydrated Silica Exterior Produced by Biomimetic Silicification Confers Viral Vaccine Heat-Resistance

Heat-lability is a key roadblock that strangles the widespread applications of many biological products. In nature, archaeal and extremophilic organisms utilize amorphous silica as a protective biomineral and exhibit considerable thermal tolerance. Here we present a bioinspired approach to generate thermostable virus by introducing an artificial hydrated silica exterior on individual virion. Similar to thermophiles, silicified viruses can survive longer at high temperature than their wild-type relatives. Virus inactivation assays showed that silica hydration exterior of the modified virus effectively prolonged infectivity of viruses by ∼ 10-fold at room temperature, achieving a similar result as that obtained by storing native ones at 4 °C. Mechanistic studies indicate that amorphous silica nanoclusters stabilize the inner virion structure by forming a layer that restricts molecular mobility, acting as physiochemical nanoanchors. Notably, we further evaluate the potential application of this biomimetic strategy in stabilizing clinically approved vaccine, and the silicified polio vaccine that can retain 90% potency after the storage at room temperature for 35 days was generated by this biosilicification approach and validated with in vivo experiments. This approach not only biomimetically connects inorganic material and living virus but also provides an innovative resolution to improve the thermal stability of biological agents using nanomaterials.

High efficient multifunctional Ag3PO4 loaded hydroxyapatite nanowires for water treatment.

Organic, inorganic, and biological pollutants are typical water contaminants and they seriously affect water quality. In this study, we suggested that a novel multifunctional Ag3PO4 loaded hydroxyapatite (HAP) material can remove the typical pollutants from water. The Ag3PO4/HAP composites were synthesized facilely via in-situ precipitation of Ag3PO4 on the pre-existing HAP nanowires. By optimizing the composition of Ag3PO4 and HAP, the material could achieve an optimal photocatalytic activity to decompose rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) under visible light irradiations with enhanced pH stability. Besides, the adsorption of Pb(II) on the Ag3PO4/HAP reached a maximum capacity of 250 mg/g and this value was approximately three times as that of pure HAP. Furthermore, the composite material exhibited excellent antibacterial activities towards gram-negative bacterium (Escherichia coli) and gram-positive bacterium (Stphylococcus aureus). The results highlighted the cooperative effect between Ag3PO4 and hydroxyapatite (HAP). The simultaneous removals of dyes, toxic metal ions, and bacteria with a high efficiency followed an easy approach for the purification of contaminated water via the rationally designed material, in which the Ag3PO4/HAP composite might be developed as a general water treatment material with multiple functions.

Virus capture and destruction by label-free graphene oxide for detection and disinfection applications.

Graphene oxide (GO) can efficiently capture viruses, destroy their surface proteins, and extract viral RNA in an aqueous environment by using the superficial bioreduction of GO. It follows from these phenomena that GO is an excellent nanomaterial for the high-throughput detection and disinfection of viruses, demonstrating its great potential for the prevention of environmental infections.

Vaccine Engineering with Dual-Functional Mineral Shell: A Promising Strategy to Overcome Preexisting Immunity.

Dual-functional biomineral-vaccine core-shell nanohybrids are obtained using recombinant adenovirus serotype 5 (rAd5) as templates, which efficiently masks the neutralizing epitope of vaccines and preserve their original immunogenicity. The versatile vaccine hybrid can evade the preexisting anti-Ad5 immunity, leading to boosted multifunctional antigen-specific cytokine-secreting T cell responses and presenting promising applications of vaccine-material hybrid for the rational design of vaccines.

Mineralized State of the Avian Influenza Virus in the Environment

Although the circulation of avian influenza viruses in humans is limited, they can be transmitted from Aves (birds) to humans, representing a great challenge. Herein, we suggest that influenza viruses from Aves might exist in a mineralized state owing to the high calcium concentrations in the avian intestine. Using two typical influenza viruses as examples, we demonstrate that these viruses can self-mineralize in simulated avian intestinal fluid, resulting in egg-like virus-mineral structured composites. The mineralized viruses are more robust, with enhanced infectivity and thermostability. More importantly, the mineral exterior of mineralized viruses can alter their cell internalization, expanding the possible tropisms. The discovery of a mineralized state of influenza viruses highlights the integration of nanomaterials and viruses in the environment, which provides a new understanding of avian influenza infection and its control.