Novel polymer composite coated with ethylcellulose nanoparticle from waste paper as an alternative material to extracorporeal oxygenation membrane

Extracorporeal membrane oxygenator (ECMO) is a valuable technology to support people with acute respiratory distress syndrome (ARDS) and is recommended for COVID-19 patients. This study aims to fabricate polymer-based composite membranes coated with ethylcellulose nanoparticles from waste paper and identify the performance of the composite as ECMO candidates. Composite membranes were made from four types of polymers, namely, nylon, PTFE (polytetrafluoroethylene), Pebax® MH-1657, and SBS (poly-(styrene-b-butadiene-b-styrene)). PDMS (polydimethylsiloxane) 1 wt.% and ethylcellulose nanoparticles (3% and 10 wt.%) were used as membrane coatings to increase their hydrophobic properties. The success of cellulose isolation and ethylcellulose synthesis from waste paper was confirmed by the FTIR and XRD analysis. The size of the synthesized ethylcellulose nanoparticles was 32.68 nm. The coating effect on composite membranes was studied by measuring the contact angle, membrane porosity, protein quantification tests, and single gas permeation of O2 and CO2. Based on the protein quantification test, the protein could not pass through the Pebax/PDMS and SBS/PDMS composites coated with 10 wt.% ethylcellulose;this indicated less risk of plasma leakage. The gas permeation test on nylon/PDMS, PTFE/PDMS, and SBS/PDMS composites coated with 10% ethylcellulose resulted high CO2/O2 selectivity, respectively, 2.17, 3.48, and 3.22 as good indication for extracorporeal oxygenation membrane.

Effect of carbonmineral sorbent with nanofiber on the parameters of erythrocytes of erythrocyte concentrates IN VITRO

As preventive, curative and restorative measures in modern conditions of the spread of infectious diseases (Covid 19), the use of sorption materials and detoxification methods with their use in hemosorption are of particular importance. It is known that hemosorption is an effective method of detoxification of the body, and no less important is the use of safe sorbents in relation to the shaped elements of blood, both time-tested sorbents and new, less studied, but more promising from the point of view of their safe production technology. The purpose of this work is to study with the help of scanning flow cytometry the effect of a sorbent with carbon nanofiber A1203@PDMS/CNF in comparison with a carbon-free sorbent A1203@PDMS on morphofunctional parameters erythrocytes. The study of the physico-chemical properties of sorbents was carried out according to standard methods. The biological properties of sorbents were evaluated by its effect on erythrocytes of erythrocyte concentrate during hemoperfusion of blood through columns with sorbents using the method of scanning flow cytometry according to the standard method. The data obtained using the method of scanning flow cytometry made it possible to conclude that the studied sorbents do not have a traumatic effect on the morphofunctional parameters of erythrocytes. The introduction of carbon nanofiber into the composition of the sorbent in an amount of 0.02% improves the functional parameters of blood erythrocytes both in comparison with the initial donor blood and compared to the sorbent without carbon. © 2022 IEEE.

DESIGN OPTIMIZATION OF MICROFLUIDIC DIAGNOSTIC DEVICES FOR THE RAPID GENETIC DETECTION OF MULTIPLE INFECTIOUS VIRUSES

This paper presents a newly developed microfluidic flow control theory for autonomous sample dispensing into an array of reaction microchambers. The theoretical predictions for the possible dispensing number and maximum flow rate were validated by comparison to experimental results. Moreover, we successfully demonstrated the rapid genetic detection of multiple infectious viruses including SARS-CoV-2 in fabricated polydimethylsiloxane (PDMS)-based microfluidic devices based on the loop-mediated isothermal amplification (LAMP) method. © 2021 MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.

Surface engineering using PDMS and functionalized nanoparticles for superhydrophobic coatings: Selective liquid repellence and tackling COVID-19

Recently, synthesis and design of bioinspired nanostructured coated surfaces with exceptional selective liquid repellency (superhydrophobicity) have been a fascinating area of research because of their excellent utility in various applications from our daily life to industry level. In this context, superhydrophobic coatings by the use of polydimethylsiloxane (PDMS) along with functionalized nanoparticles have been reported widely for oil/water separation, antimicrobial ability and antiviral surface coatings to prevent the transmission of contagious coronavirus disease 2019 (COVID-19). PDMS is mechanically stable and highly flexible silicone polymer and can be irreversibly bound to various types of surfaces in order to provide superhydrophobicity. This review highlights the latest innovations in the research area of PDMS based nano-engineered superhydrophobic coatings on various surfaces. Particular attention has been paid toward the application of such superhydrophobic surfaces for the separation of oily contaminants from water as well as antimicrobial and antiviral efficacy in order to reduce the transmission of toxic pathogens including contagious COVID-19. Technical breakthrough and mechanistic concepts behind the success of PDMS based superhydrophobic coatings have been reviewed and discussed in these selected applications. It is expected that this study will be highly useful to lead future research in order to tackle the transmission of viral outbreaks in the coming future similar to the currently ongoing pandemic of COVID-19.

Face mask detection and recognition using an IoT enabled PDMS-Ag e-skin sensor that works in contact and non-contact modes

The COVID-19 pandemic has already spread over 200 countries in a few months and taken a toll on many lives. At this critical time, there is a need to follow some precautions to control the virus spreading rapidly through direct and indirect contact. The World Health Organization (WHO) has already recommended the importance of face masks for protection from the virus. Hence, one of the prime changes we have had to incorporate in our lives is wearing a face mask. This work reports the development of Ag particles containing polydimethylsiloxane (PDMS) based e-skin sensor, which generates signals on touch (contact mode) or proximity (non-contact mode) near the sensor. These signals are retrieved using IoT. The signals indicate a person's presence, which activates face mask detection using deep learning. This model is an IoT and Machine Learning-based system. When a human touches or places a hand near the PDMS-Ag sensor, this model performs face masks detection. This model is also suitable for security purposes. Since controlling the number of new COVID-19 cases is the need of the hour, we are using face mask detection in this study. © 2021 IEEE.

Fabrication of Wearable PDMS Device for Rapid Detection of Nucleic Acids via Recombinase Polymerase Amplification Operated by Human Body Heat.

Pathogen detection by nucleic acid amplification proved its significance during the current coronavirus disease 2019 (COVID-19) pandemic. The emergence of recombinase polymerase amplification (RPA) has enabled nucleic acid amplification in limited-resource conditions owing to the low operating temperatures around the human body. In this study, we fabricated a wearable RPA microdevice using poly(dimethylsiloxane) (PDMS), which can form soft-but tight-contact with human skin without external support during the body-heat-based reaction process. In particular, the curing agent ratio of PDMS was tuned to improve the flexibility and adhesion of the device for better contact with human skin, as well as to temporally bond the microdevice without requiring further surface modification steps. For PDMS characterization, water contact angle measurements and tests for flexibility, stretchability, bond strength, comfortability, and bendability were conducted to confirm the surface properties of the different mixing ratios of PDMS. By using human body heat, the wearable RPA microdevices were successfully applied to amplify 210 bp from Escherichia coli O157:H7 (E. coli O157:H7) and 203 bp from the DNA plasmid SARS-CoV-2 within 23 min. The limit of detection (LOD) was approximately 500 pg/reaction for genomic DNA template (E. coli O157:H7), and 600 fg/reaction for plasmid DNA template (SARS-CoV-2), based on gel electrophoresis. The wearable RPA microdevice could have a high impact on DNA amplification in instrument-free and resource-limited settings.

Future antiviral polymers by plasma processing.

Coronavirus disease 2019 (COVID-19) is largely threatening global public health, social stability, and economy. Efforts of the scientific community are turning to this global crisis and should present future preventative measures. With recent trends in polymer science that use plasma to activate and enhance the functionalities of polymer surfaces by surface etching, surface grafting, coating and activation combined with recent advances in understanding polymer-virus interactions at the nanoscale, it is promising to employ advanced plasma processing for smart antiviral applications. This trend article highlights the innovative and emerging directions and approaches in plasma-based surface engineering to create antiviral polymers. After introducing the unique features of plasma processing of polymers, novel plasma strategies that can be applied to engineer polymers with antiviral properties are presented and critically evaluated. The challenges and future perspectives of exploiting the unique plasma-specific effects to engineer smart polymers with virus-capture, virus-detection, virus-repelling, and/or virus-inactivation functionalities for biomedical applications are analysed and discussed.

Current state of diagnostic, screening and surveillance testing methods for COVID-19 from an analytical chemistry point of view.

Since December 2019, we have been in the battlefield with a new threat to the humanity known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this review, we describe the four main methods used for diagnosis, screening and/or surveillance of SARS-CoV-2: Real-time reverse transcription polymerase chain reaction (RT-PCR); chest computed tomography (CT); and different complementary alternatives developed in order to obtain rapid results, antigen and antibody detection. All of them compare the highlighting advantages and disadvantages from an analytical point of view. The gold standard method in terms of sensitivity and specificity is the RT-PCR. The different modifications propose to make it more rapid and applicable at point of care (POC) are also presented and discussed. CT images are limited to central hospitals. However, being combined with RT-PCR is the most robust and accurate way to confirm COVID-19 infection. Antibody tests, although unable to provide reliable results on the status of the infection, are suitable for carrying out maximum screening of the population in order to know the immune capacity. More recently, antigen tests, less sensitive than RT-PCR, have been authorized to determine in a quicker way whether the patient is infected at the time of analysis and without the need of specific instruments.

Microneedle-based devices for point-of-care infectious disease diagnostics.

Recent infectious disease outbreaks, such as COVID-19 and Ebola, have highlighted the need for rapid and accurate diagnosis to initiate treatment and curb transmission. Successful diagnostic strategies critically depend on the efficiency of biological sampling and timely analysis. However, current diagnostic techniques are invasive/intrusive and present a severe bottleneck by requiring specialist equipment and trained personnel. Moreover, centralised test facilities are poorly accessible and the requirement to travel may increase disease transmission. Self-administrable, point-of-care (PoC) microneedle diagnostic devices could provide a viable solution to these problems. These miniature needle arrays can detect biomarkers in/from the skin in a minimally invasive manner to provide (near-) real-time diagnosis. Few microneedle devices have been developed specifically for infectious disease diagnosis, though similar technologies are well established in other fields and generally adaptable for infectious disease diagnosis. These include microneedles for biofluid extraction, microneedle sensors and analyte-capturing microneedles, or combinations thereof. Analyte sampling/detection from both blood and dermal interstitial fluid is possible. These technologies are in their early stages of development for infectious disease diagnostics, and there is a vast scope for further development. In this review, we discuss the utility and future outlook of these microneedle technologies in infectious disease diagnosis.

Flexible, Highly Sensitive Paper-Based Screen Printed MWCNT/PDMS Composite Breath Sensor for Human Respiration Monitoring.

Accurate measurement and monitoring of respiration is vital in patients affected by severe acute respiratory syndrome coronavirus - 2 (SARS-CoV-2). Patients with severe chronic diseases and pneumonia need continuous respiration monitoring and oxygenation support. Existing respiratory sensing techniques require direct contact with the human body along with expensive and heavy Holter monitors for continuous real-time monitoring. In this work, we propose a low-cost, non-invasive and reliable paper-based wearable screen printed sensor for human respiration monitoring as an effective alternative of existing sensing systems. The proposed sensor was fabricated using traditional screen printing of multi-walled carbon nanotubes (MWCNTs) and polydimethylsiloxane (PDMS) composite based interdigitated electrodes on paper substrate. The paper substrate was used as humidity sensing material of the sensor. The hygroscopic nature of paper during inhalation and exhalation causes a change in dielectric constant, which in turn changes the capacitance of the sensor. The composite interdigitated electrode configuration exhibited better response times with a rise time of 1.178s being recorded during exhalation and fall time of 0.88s during inhalation periods. The respiration rate of sensor was successfully examined under various breathing conditions such as normal breathing, deep breathing, workout, oral breathing, nasal breathing, fast breathing and slow breathing by employing it in a wearable mask, a mandatory wearable product during the current COVID-19 pandemic situation.Thus, the above proposed sensor may hold tremendous potential in wearable/flexible healthcare technology with good sensitivity, stability, biodegradability and flexibility at this time of need.