Photocatalytic Inactivation of Pathogenic Viruses Using Metal Oxide and Carbon-Based Nanoparticles
Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji in Viral and Antiviral Nanomaterials, 2022
Woo et al. (2012) designed a microwave-irradiation-assisted filtration system to inactivate viral aerosols, which can reach a high inactivation efficiency of around 5-log. Xia et al. (2019) demonstrated the efficacy of nonthermal plasma (NTP) against MS2 virus using a packed bed nonthermal plasma reactor. Approximately 2.3-log virus was reduced in which ~2-log of the MS2 inactivated and ~0.35-log physically removed in the packed bed. Wigginton et al. (2012) used five different disinfectants, such as free chlorine (FC), heat, UV irradiation, singlet oxygen, and chlorine dioxide (ClO2), to inactivate MS2 virus. They found that each treatment method resulted in a unique inactivation mechanism. For example, ClO2 or heat treatments may be suitable for inactivating double-stranded DNA viruses with genome repair mechanisms. UV treatment was more effective for inactivating single-stranded RNA viruses without genome repair mechanisms. Nonthermal plasma (NTP) produces chemically active species, such as atomic oxygen, hydroxyl radicals, and ozone, to remove bioaerosol. However, the production of toxic byproduct, such as CO, O3, NOX and aerosol particles, restricts its application (Yu et al. 2009). Other conventional methods like UV irradiation, thermal treatment, and microwave irradiation are not practical because they require high energy consumption. Therefore, heterogeneous photocatalysis has recently emerged as an alternative technology to the current viral inactivation since the foremost discovery by Sjogren and Sierka (1994).
Lactic acid-based polymers in depth
Yoshinobu Onuma, Patrick W.J.C. Serruys in Bioresorbable Scaffolds, 2017
As for exploitation-related properties, PLA-type polymers, especially amorphous ones, can absorb water slowly from a humid atmosphere which can cause slow hydrolytic degradation that results in undesired aging. Rearrangements of more or less oriented chain conformation, a phenomenon referred to as chain relaxation, can occur very slowly below Tg to affect dimensions and stability on storage. Sterilization is also a source of problems because there is a risk of fast deformation (above Tg) and thermal degradation if heat is used. In the case of radiation-based sterilization, severe decreases of molecular mass are observed and cross-linking has been suggested. Sterilization by cold plasma seems to be the best characteristic-respecting process with very small molecular weight decreases although some surface functionalization may change protein adsorption.
Ecology
Paul Pumpens in Single-Stranded RNA Phages, 2020
Recently, the phage MS2 contributed to the generation of novel microorganism aerosol collectors (Lin XT et al. 2018; Pan M et al. 2018, 2019a,b; Yu et al. 2018). Schaeffer et al. (2018) used the phage MS2 to achieve the detection of viruses from bioaerosols using anion exchange resin. Concerning the inactivation of the aerosolized viruses, the phage MS2 served as a model for approaches using (i) vacuum UV photocatalysis for a flowthrough indoor air purifier with short irradiation time (Kim J and Jang 2018), (ii) noncontact ultrasonic transducer bound in high-efficiency particulate air (HEPA), filters (Versoza et al. 2018), and (iii) a packed bed nonthermal plasma reactor (Xia et al. 2019).
Efficacy of cavity liners with/without atmospheric cold helium plasma jet for dentin remineralization
Published in Biomaterial Investigations in Dentistry, 2020
Hamid Kermanshah, Reza Saeedi, Elham Ahmadi, Ladan Ranjbar Omrani
Plasma is the 4th state of matters that forms at very high temperatures. This ionized gas includes photons, electrons, positive and negative ions, atoms, free radicals, and excited and non-excited molecules that constantly interact with each other [11]. Plasma has different types including hot, warm and cold plasma. The cold plasma is a type of plasma created by electrical discharge [12]. Of different methods of production of cold plasma, plasma jet has gained attention since it is portable, can be charged on spot and has low energy consumption. The ACPJ has low temperature (room temperature) and therefore, has several medical applications [13]. Researchers have shown that plasma surface modification is a clean and effective method [10]. Its effect is related to plasma reactive species. According to the plasma type, the plasma gas reacts with the surface of substrates and creates new surface characteristics [10]. Increased wettability, as well as permeability, is among the modifications caused by argon and helium plasma in dental substrates [10].
Non-thermal techniques: a new approach to removing pesticide residues from fresh products and water
Published in Toxin Reviews, 2021
Reza Abedi-Firoozjah, Zahra Ghasempour, Sirous Khorram, Arezou Khezerlou, Ali Ehsani
Many sterilization techniques have been used for the degradation of pesticide residues, including conventional thermal methods, ozonation, UV irradiation, ultrasonic and ionizing radiation, photolysis, and hydrolysis. However, these methods are potentially hazardous, highly costly, and offer minimal efficiency (Mousavi et al. 2017). In the past decade, studies in food science have focused largely on physical and non-thermal technologies such as cold plasma (CP), pulsed electric field (PEF), electron beam (EB), and electrolyzed water (EW). These technologies have been considered as promising methods for resolving pollution issues in recent years. Today, physical technologies are becoming more attractive due to being non-thermal, eco-friendly, inexpensive, highly efficient, and rapid. Moreover, these methods offer excellent potential to help reduce the levels of pesticide residues in foods and water while maintaining the qualitative properties and nutritional content of the products during processing. We hope that this study persuades scientists, investors, environmentalists, and food policymakers to pay more attention to the application of these technologies. The main aims of this review were to investigate the parameters influential on decontamination efficiency, mechanism of degradation, applications, and advantages/disadvantages of physical, non-thermal technologies for the reduction of pesticide residue levels in fresh products and water.
Topical negative-pressure wound therapy: emerging devices and techniques
Published in Expert Review of Medical Devices, 2020
Raymund E. Horch, Ingo Ludolph, Wibke Müller-Seubert, Katharina Zetzmann, Theresa Hauck, Andreas Arkudas, Alexander Geierlehner
Cold plasma, one of the four fundamental states of matter, was recently introduced as a promising application to enhance wound healing. Especially in chronic and heavily contaminated wounds, the combination of cold plasma with sub-atmospheric pressure could be beneficial to the wound healing process. An increasing number of drug-resistant bacteria and the lack of new antibiotics make further optimization of NPWT as a delivery vehicle worthy. The delivery of adjunct therapies such as saline irrigation or instillation with antimicrobial solutions is increasingly used in the clinical wound management [116,122]. Wound instillation possesses the ability to deliver wound dependent and wound-specific substances. Cell suspensions containing prefabricated stem cells derived from the affected patient might also be able to promote wound healing. However, this is highly dependent on the type of tissue involved. Furthermore, substances known to have an impact on the physiological wound healing process could be applied in combination with NPWT in future studies. The combination with later techniques of tissue regeneration, such as tissue engineering and bioprinting in conjunction with biomolecular insights seems desirable, yet is not in the stage of clinical application [1]. Different vascular and collagen related growth factors might be of high interest [123]. Also applying perioperative analgesia or antibiotics using substances that interact directly at the foam–wound interface is a possible modification in the overall treatment concept of NPTW. Basic research for the detailed understanding of cell signaling mechanism is essential in this context.
Related Knowledge Centers
- Food Processing
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- Syngas
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