Efficient and fast degradation of 4-nitrophenol and detection of Fe(III) ions by Poria cocos extract stabilized silver nanoparticles

In this study, a simple and environment-friendly method has been successfully applied for the production of silver nanoparticles (AgNPs) using Poria cocos extract. The reaction time of 60 min, the temperature of 90◦ C, and silver ion concentration of 2.0 mM were identified as the best condition for the PC-AgNPs fabrication. The XRD analysis confirmed a highly crystalline face-centered cubic structure of the biosynthesized material. The PCAgNPs were presented separately in a spherical shape with an average crystal size of 20 nm, as endorsed by the TEM and FE-SEM measurement

Nanomaterial for Adjuvants Vaccine: Practical Applications and Prospects

Vaccines contain adjuvants to strengthen the immune responses of the receiver against pathogen infection or malignancy. A new generation of adjuvants is being developed to give more robust antigen-specific responses, specific types of immune responses, and a high margin of safety. By changing the physical and chemical properties of nanomaterials, it is possible to make antigen-delivery systems with high bioavailability, controlled and sustained release patterns, and the ability to target and image. Nanomaterials can modulate the immune system so that cellular and humoral immune responses more closely resemble those desired. The use of nanoparticles as adjuvants is believed to significantly improve the immunological outcomes of vaccination because of the combination of their immunomodulatory and delivery effects. In this review, we discuss the recent developments in new adjuvants using nanomaterials. Based on three main vaccines, the subunit, DNA, and RNA vaccines, the possible ways that nanomaterials change the immune responses caused by vaccines, such as a charge on the surface or a change to the surface, and how they affect the immunological results have been studied. This study aims to provide succinct information on the use of nanomaterials for COVID-19 vaccines and possible new applications

Nanosized Zincated Hydroxyapatite as a Promising Heterogeneous Photo-Fenton-Like Catalyst for Methylene Blue Degradation

This study is devoted to synthesis of nanosized zincated hydroxyapatite (Zn-HA) and its utilization as a heterogeneous photo-Fenton-like catalyst for degradation of methylene blue (MB) in aqueous solution. The prepared catalyst was characterized by various techniques such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray, and Fourier transform infrared spectroscopy. The catalytic activity of Zn-HA towards MB and the effects of various experimental factors such as pH, zinc substitution degrees, initial MB concentration, and H2O2 dosage were studied in detail. The results showed that the zinc substitution degree of 0.4 is optimal to get the highest degradation efficiency under conditions of pH = 10, H2O2 dosage of 0.05 M, and MB concentration of 30 mg/L for a contact time of 120 min. The degradation mechanism was proposed and discussed thoroughly. Besides, the ability of long-term use for the synthesized catalyst was also evaluated

Utilization of Mn-Doped ZnSe/ZnS Core/Shell Quantum Dots for Rapid Detection of Escherichia coli O157:H7 and Methicillin-Resistant Staphylococcus aureus

In this study, Mn-doped ZnSe/ZnS core/shell quantum dots (CSQDs) were synthesized in aqueous solution using polyethylene glycol as a surface stabilizer and successfully applied in the detection of Escherichia coli O157:H7 and methicillin-resistant Staphylococcus aureus (MRSA) for the first time. The CSQDs were conjugated with anti-E. coli antibody and anti-MRSA antibody via protein A supported by 1-ethyl-3-(-3-dimethylaminopropyl)carbodiimide hydrochloride for fluorescent labeling of the intact bacterial cells. The detection was performed for the bacterial strains cultivated in Luria-Bertani liquid medium. The obtained results indicate that E. coli O157:H7 and MRSA can be detected within 30 min at a high sensitivity of 101 CFU/mL. This labeling method based on the highly fluorescent CSQDs may have great potential for use in the food industry to check and prevent outbreaks of foodborne illness