Nanobiocide Based-Silver Nanomaterials Upon Coronaviruses: Approaches for Preventing Viral Infections

Abstract The effectiveness of silver nanomaterials (AgNMs), as antiviral agents, has been confirmed in humans against many different types of viruses. Nanobiocides-based AgNMs can be effectively applied to eliminate coronaviruses (CoVs), as the cause of various diseases in animals and humans, particularly the fatal human respiratory infections. Mostly, these NMs act effectively against CoVs, thanks to the NMs’ fundamental anti-viral structures like reactive oxygen species (ROS), and photo-dynamic and photo-thermal abilities. Particularly, the antiviral activity of AgNMs is clarified under three inhibitory mechanisms including viral entry limitation, attachment inhibition, and viral replication limitation. It is believed that nanobiocide with other possible materials such as TiO2, silica and, carbon NMs exclusively nano-graphene materials can emerge as a more effective disinfectant for long-term stability with low toxicity than common disinfectants. Nanobiocides also can be applied for the prevention and treatment of viral infections specifically against COVID-19. Graphic Abstrac

Recent Advances of Cellulase Immobilization onto Magnetic Nanoparticles: An Update Review

Cellulosic enzymes, including cellulase, play an important role in biotechnological processes in the fields of food, cosmetics, detergents, pulp, paper, and related industries. Low thermal and storage stability of cellulase, presence of impurities, enzyme leakage, and reusability pose great challenges in all these processes. These challenges can be overcome via enzyme immobilization methods. In recent years, cellulase immobilization onto nanomaterials became the focus of research attention owing to the surface features of these materials. However, the application of these nanomaterials is limited due to the efficacy of their recovery process. The application of magnetic nanoparticles (MNPs) was suggested as a solution to this problem since they can be easily removed from the reaction mixture by applying an external magnet. Recently, MNPs were extensively employed for enzyme immobilization owing to their low toxicity and various practical advantages. In the present review, recent advances in cellulase immobilization onto functionalized MNPs is summarized. Finally, we discuss enhanced enzyme reusability, activity, and stability, as well as improved enzyme recovery. Enzyme immobilization techniques offer promising potential for industrial applications

Application of Electrospun Nanofibrous PHBV Scaffold in Neural Graft and Regeneration: A Mini-Review

Among the synthetic polymers, poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) microbial polyester is one of the biocompatible and biodegradable copolymers in the nanomedicine scope. PHBV has key points and suitable properties to support cellular adhesion, proliferation and differentiation of nanofibers. Nanofibers are noticeably employed in order to enhance the performance of biomaterials, and could be effectively considered in this scope. Electrospinning is one of the well-known and practical methods that extremely employed in the construction of nanofibrous scaffolds for biomedical application and recently PHBV has exploited in nerve graft and regenerative medicine. PHBV composites nanofibrous scaffolds are able to be applied as promising materials in many fields, such as; wound healing and dressing, tissue engineering, targeted drug delivery systems, functional carries, biosensors or nano-biosensors and so on. In this mini-review, we attempt to provide a more detailed overview of the recent advances of PHBV electrospun nanofibers application in neural graft and regeneration

Investigation of acute dermal irritation/corrosion, acute inhalation toxicity and cytotoxicity tests for Nanobiocide®

Objective(s): Nanomaterials, especially silver Nanoparticles (Ag-NPs), are employed in an increasing number of commercial products. This has led to an ever growing exposure of human beings to this substance. The first purpose of the Nano Committee of Food and Drug Administration of The Islamic Republic of Iran (IFDA) is developing guidelines to assess and approve commercial nano-health products for their safety of human applications. Nanobiocide® as a commercial product of stable colloid including 2000 ppm Ag-NPs for surface antimicrobial applications was investigated according to IFDA guidelines in the approval process. Methods: The first fabrication and characterization method of the product were determined. The human exposure to Nanobiocide® were studied by cytotoxicity assay, dermal irritation and inhalation toxicity assay based on the standard assay. Results: According to cytotoxicity assay by MTT method the concentration-dependent of cell viability was reduced and Inhibitory concentration-50 was about 1160 ppm. The Draize dermal irritation scoring system (DDIS) showed no irritation to the skin of rabbits. No sign of gross toxicity, adverse pharmacological effect, or abnormal behavior based on inhalation toxicity was observed. Conclusions: The consideration of toxicity of Nanobiocide® is one of the major key for medical application. The results obtained revealed that the Nanobiocide® may be safe using in domestic and veterinary applications

Zingiber officinale and thymus vulgaris extracts co-loaded polyvinyl alcohol and chitosan electrospun nanofibers for tackling infection and wound healing promotion

Infections are severe complications associated with chronic wounds and tardy healing that should be timely treated to achieve rapid and proper tissue repair. To hinder such difficulties, a nanofibrous mat composed of polyvinyl alcohol and chitosan (PVA/CS) was developed by electrospinning method, containing thyme (Thymus vulgaris) and ginger (Zingiber officinale) extracts. The mat containing 10 wt% of the extracts (at the ratio of 50:50) exposed the nanofibers (NFs) with the nanoscale diameter (average 382 ± 60 nm), smooth surface, and defect-free morphology. Likewise, the relevant analyses of the loaded mat displayed high wettability, porosity, and liquid absorption capacity without any adverse interaction. The obtained mat also provided a high antioxidant activity, and its release profile was continuous and sustained for nearly 72 h. Besides, it inhibited the growth of both Gram-positive S. aureus and Gram-negative E. coli strains. Furthermore, the proposed mat significantly accelerated cutaneous wound healing in bacterial-infected rats by preventing bacteria growth at the wound site. At last, histopathology analysis confirmed the ample regeneration of skin structures, forming collagen fibers and appendages. Overall, the proposed mat containing ginger-thyme extracts provides multiple therapeutic capabilities with promising solutions for inhibiting wound infection and accelerating the healing process