Virus Removal and Inactivation Mechanisms during Iron Electrocoagulation: Capsid and Genome Damages and Electro-Fenton Reactions

2021 ◽  
Author(s):  
Kyungho Kim ◽  
Jothikumar Narayanan ◽  
Anindito Sen ◽  
Shankararaman Chellam
Keyword(s):  
Virus Removal

Virus Removal by Filtration

1982 ◽  
Vol 14 (4-5) ◽  
pp. 253-256
Author(s):  
N Sriramula ◽  
M Chaudhuri
Keyword(s):  
Experimental Data ◽  
Escherichia Coli ◽  
Cationic Polyelectrolyte ◽  
Electrokinetic Phenomena ◽  
Virus Removal ◽  
Bacterial Virus ◽  
Gravity Settling ◽  
And Diffusion ◽  
Model Virus ◽  
Good Agreement

An investigation was undertaken on the removal of a model virus, bacterial virus MS2 against Escherichia coli, by sand filtration using untreated, and alum or cationic polyelectrolyte treated media, and uncoagulated as well as alum coagulated influent. Data on discrete virus removal were satisfactorily accounted for by electrokinetic phenomena and diffusion. For virus in association with turbidity, filter coefficients computed from experimental data were in good agreement with those predicted by mechanical straining and gravity settling which were the dominant mechanisms for removal of the turbidity particles to which the viruses attached.

A New Technique for the Enumeration of Rotaviruses in Wastewater Samples

1989 ◽  
Vol 21 (3) ◽  
pp. 99-104 ◽  
Author(s):  
J. I. Oragui ◽  
D. D. Mara ◽  
S. A. Silva ◽  
A. M. Konig
Keyword(s):  
Inorganic Ions ◽  
Assay Method ◽  
Toxic Substances ◽  
Waste Stabilization Ponds ◽  
Virus Removal ◽  
Molecular Weights ◽  
Large Numbers ◽  
Waste Stabilization ◽  
A New Technique ◽  
Wastewater Samples

Rotaviruses are generally excreted in large numbers in diarrhoeal stools, but in wastewaters their numbers are subject to variations. Detection and enumeration of these viruses involve a concentration step followed by an assay method. Enumeration in wastewater concentrates is complicated by the presence of toxic substances which are often concentrated with the viruses. These toxic substances often cause the destruction of cells during rotavirus assay, thus leading to underestimation of viral numbers. Such concentrates were detoxified by a simple and effective method using polyacrylamide (Biogel P-6DG) or dextran (Sephadex G50) beads. Concentrates (10 ml) were mixed with 0.5 g gel and the mixtures were allowed to stand for 2 h at room temperature during which time the beads swell by the passage of water into them along with inorganic ions and substances with molecular weights of less than 30,000. The supernatants were then decontaminated with antibiotics and assayed for rotaviruses by the indirect immunofluorescent technique. Most untreated ultrafiltrates of raw sewage and those from anaerobic ponds were found to be too toxic to MA104 and LLC MK2 cells, whereas the above treatment rendered over 90% of wastewater concentrates non-toxic to cells. This technique was used to study virus removal in samples from deep waste stabilization ponds in northeast Brazil.

scholarly journals Direct visualization of virus removal process in hollow fiber membrane using an optical microscope

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Miku Ayano ◽  
Yoshiyuki Sawamura ◽  
Tomoko Hongo-Hirasaki ◽  
Takayuki Nishizaka
Keyword(s):  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Imaging Techniques ◽  
Basic Research ◽  
Optical Microscope ◽  
Regenerated Cellulose ◽  
Fiber Membrane ◽  
Virus Removal ◽  
Novel Method ◽  
Pass Through

AbstractVirus removal filters developed for the decontamination of small viruses from biotherapeutic products are widely used in basic research and critical step for drug production due to their long-established quality and robust performance. A variety of imaging techniques have been employed to elucidate the mechanism(s) by which viruses are effectively captured by filter membranes, but they are limited to ‘static’ imaging. Here, we propose a novel method for detailed monitoring of ‘dynamic process’ of virus capture; specifically, direct examination of biomolecules during filtration under an ultra-stable optical microscope. Samples were fluorescently labeled and infused into a single hollow fiber membrane comprising cuprammonium regenerated-cellulose (Planova 20N). While proteins were able to pass through the membrane, virus-like particles (VLP) accumulated stably in a defined region of the membrane. After injecting the small amount of sample into the fiber membrane, the real-time process of trapping VLP in the membrane was quantified beyond the diffraction limit. The method presented here serves as a preliminary basis for determining optimum filtration conditions, and provides new insights into the structure of novel fiber membranes.

scholarly journals Aggregate Removal Nanofiltration of Human Serum Albumin Solution Using Nanocellulose-Based Filter Paper

Biomedicines ◽  
2020 ◽  
Vol 8 (7) ◽  
pp. 209 ◽  
Author(s):  
Lulu Wu ◽  
Athanasios Mantas ◽  
Simon Gustafsson ◽  
Levon Manukyan ◽  
Albert Mihranyan
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Filter Paper ◽  
High Performance ◽  
Size Exclusion ◽  
Transmembrane Pressure ◽  
Protein Loss ◽  
Virus Removal ◽  
Model Virus

This study is dedicated to the rapid removal of protein aggregates and viruses from plasma-derived human serum albumin (HSA) product to reduce the risk of viral contamination and increase biosafety. A two-step filtration approach was implemented to first remove HSA aggregates and then achieve high model virus clearance using a nanocellulose-based filter paper of different thicknesses, i.e., 11 μm (prefilter) and 22 μm (virus filter) at pH 7.4 and room temperature. The pore size distribution of these filters was characterized by nitrogen gas sorption analysis. Dynamic light scattering (DLS) and size-exclusion high performance liquid chromatography (SE-HPLC) were performed to analyze the presence of HSA aggregates in process intermediates. The virus filter showed high clearance of a small-size model virus, i.e., log10 reduction value (LRV) > 5, when operated at 3 and 5 bar, but a distinct decrease in LRV was detected at 1 bar, i.e., LRV 2.65–3.75. The throughput of HSA was also dependent on applied transmembrane pressure as was seen by Vmax values of 110 ± 2.5 L m−2 and 63.6 ± 5.8 L m−2 at 3 bar and 5 bar, respectively. Protein loss was low, i.e., recovery > 90%. A distribution of pore sizes between 40 nm and 60 nm, which was present in the prefilter and absent in the virus filter, played a crucial part in removing the HSA aggregates and minimizing the risk of virus filter fouling. The presented results enable the application of virus removal nanofiltration of HSA in bioprocessing as an alternative to virus inactivation methods based, e.g., on heat treatment.

Efficacy of electrochemical membrane bioreactor for virus removal from wastewater: Performance and mechanisms

2021 ◽  
pp. 124946
Author(s):  
Mei Chen ◽  
Qian Lei ◽  
Lehui Ren ◽  
Jiayi Li ◽  
Xuesong Li ◽  
...  
Keyword(s):  
Membrane Bioreactor ◽  
Virus Removal

scholarly journals Rotavirus Virus-Like Particles as Surrogates in Environmental Persistence and Inactivation Studies

2004 ◽  
Vol 70 (7) ◽  
pp. 3904-3909 ◽  
Author(s):  
Santiago Caballero ◽  
F. Xavier Abad ◽  
Fabienne Loisy ◽  
Françoise S. Le Guyader ◽  
Jean Cohen ◽  
...  
Keyword(s):  
Fluorescent Protein ◽  
Uv Light ◽  
Expression System ◽  
Baculovirus Expression System ◽  
Virus Removal ◽  
Virus Like Particles ◽  
Reverse Transcription Pcr ◽  
Actual Field ◽  
Uv Dose ◽  
Green Fluorescent

ABSTRACT Virus-like particles (VLPs) with the full-length VP2 and VP6 rotavirus capsid proteins, produced in the baculovirus expression system, have been evaluated as surrogates of human rotavirus in different environmental scenarios. Green fluorescent protein-labeled VLPs (GFP-VLPs) and particles enclosing a heterologous RNA (pseudoviruses), whose stability may be monitored by flow cytometry and antigen capture reverse transcription-PCR, respectively, were used. After 1 month in seawater at 20°C, no significant differences were observed between the behaviors of GFP-VLPs and of infectious rotavirus, whereas pseudovirus particles showed a higher decay rate. In the presence of 1 mg of free chlorine (FC)/liter both tracers persisted longer in freshwater at 20°C than infectious viruses, whereas in the presence of 0.2 mg of FC/liter no differences were observed between tracers and infectious rotavirus at short contact times. However, from 30 min of contact with FC onward, the decay of infectious rotavirus was higher than that of recombinant particles. The predicted Ct value for a 90% reduction of GFP-VLPs or pseudoviruses induces a 99.99% inactivation of infectious rotavirus. Both tracers were more resistant to UV light irradiation than infectious rotavirus in fresh and marine water. The effect of UV exposure was more pronounced on pseudovirus than in GFP-VLPs. In all types of water, the UV dose to induce a 90% reduction of pseudovirus ensures a 99.99% inactivation of infectious rotavirus. Recombinant virus surrogates open new possibilities for the systematic validation of virus removal practices in actual field situations where pathogenic agents cannot be introduced.

FIB-SEM tomography reveals the nanoscale 3D morphology of virus removal filters

2021 ◽  
pp. 119766
Author(s):  
Kaitlyn P. Brickey ◽  
Andrew L. Zydney ◽  
Enrique D. Gomez
Keyword(s):  
Virus Removal ◽  
3D Morphology

scholarly journals Evaluation of Porous Carbon Adsorbents Made from Rice Husks for Virus Removal in Water

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1280
Author(s):  
Vu Duc Canh ◽  
Seiichiro Tabata ◽  
Shun Yamanoi ◽  
Yoichi Onaka ◽  
Toshiyuki Yokoi ◽  
...  
Keyword(s):  
Porous Carbon ◽  
Activated Carbons ◽  
Carbon Adsorbents ◽  
Rice Husks ◽  
Porous Carbons ◽  
Inorganic Pollutants ◽  
Steam Activation ◽  
Virus Removal ◽  
Silica Removal ◽  
Effective Removal

Porous carbons are well-known efficient adsorbents for a variety of organic and inorganic pollutants; however, they have difficulty in virus removal. In this study, novel porous carbons (NPCs) (NPC-A, NPC-B, and NPC-C) derived from rice husks were compared with commercially available activated carbons (ACs) for their ability to remove MS2 bacteriophages (MS2) in a batch experiment. NPC-A was produced by the silica removal process. NPC-B was prepared with an additional steam activation applied to NPC-A. NPC-C was obtained with an additional acid rinse applied to NPC-B. The NPCs (particularly NPC-C) exhibited effective removal of up to 5.3 log10 of MS2, which was greater than that of less than 2.7 log10 obtained by other ACs under 10 g/L during the same contact time (60 min). The pore size distribution of the porous carbon adsorbents was found to influence their virus removal performance. The adsorbents with a larger proportion of pores ranging from 200–4500 nm in diameter were able to achieve higher virus removal rates. Thus, NPCs (particularly NPC-C), which had a larger volume of pores ranging from 200–4500 nm in size, demonstrated the potential for use as efficient adsorbents for removing viruses during water purification.

Bacteria and virus removal effectiveness of ceramic pot filters with different silver applications in a long term experiment

2014 ◽  
Vol 51 ◽  
pp. 47-54 ◽  
Author(s):  
H. van der Laan ◽  
D. van Halem ◽  
P.W.M.H. Smeets ◽  
A.I.A. Soppe ◽  
J. Kroesbergen ◽  
...  
Keyword(s):  
Virus Removal ◽  
Term Experiment ◽  
Long Term Experiment

Virus removal efficiency of ceramic water filters: effects of bentonite turbidity

2013 ◽  
Vol 14 (2) ◽  
pp. 304-311 ◽  
Author(s):  
Cameron Farrow ◽  
Edward McBean ◽  
Hamidreza Salsali
Keyword(s):  
Removal Efficiency ◽  
Potable Water ◽  
Source Water ◽  
Virus Removal ◽  
Ceramic Water Filters ◽  
Point Of Use ◽  
Cake Layer ◽  
Human Enteric Viruses ◽  
Removal Efficiencies ◽  
Water Filters

Ceramic water filters (CWFs) are utilized in many developing countries as point-of-use (POU) water treatment devices, to reduce waterborne pathogens in potable water. Virus removal efficiencies of several CWFs are investigated under various influent conditions using MS2 (ATCC: 15597-B1) as a surrogate phage for human enteric viruses. The addition of bentonite turbidity (6–8 NTU) in the influent source water showed increased viral removal efficiency of CWFs by 0.1–0.2 log compared to tests involving clear (<1 NTU) influents. Trials employing an applied clay cake layer, formed using highly turbid influent source water (100 NTU) and no cleaning regime between trials, resulted in viral removal efficiency values of 1.5–2.5 log, compared to 0.2–0.5 log during non-obstructed trials.

Sign in / Sign up

Export Citation Format

Share Document