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To manage the COVID-19 pandemic, development of rapid, selective, sensitive diagnostic systems for early stage β-coronavirus severe acute respiratory syndrome (SARS-CoV-2) virus protein detection is emerging as a necessary response to generate the bioinformatics needed for efficient smart diagnostics, optimization of therapy, and investigation of therapies of higher efficacy. The urgent need for such diagnostic systems is recommended by experts in order to achieve the mass and targeted SARS-CoV-2 detection required to manage the COVID-19 pandemic through the understanding of infection progression and timely therapy decisions. To achieve these tasks, there is a scope for developing smart sensors to rapidly and selectively detect SARS-CoV-2 protein at the picomolar level. COVID-19 infection, due to human-to-human transmission, demands diagnostics at the point-of-care (POC) without the need of experienced labor and sophisticated laboratories. Keeping the above-mentioned considerations, we propose to explore the compartmentalization approach by designing and developing nanoenabled miniaturized electrochemical biosensors to detect SARS-CoV-2 virus at the site of the epidemic as the best way to manage the pandemic. Such COVID-19 diagnostics approach based on a POC sensing technology can be interfaced with the Internet of things and artificial intelligence (AI) techniques (such as machine learning and deep learning for diagnostics) for investigating useful informatics via data storage, sharing, and analytics. Keeping COVID-19 management related challenges and aspects under consideration, our work in this review presents a collective approach involving electrochemical SARS-CoV-2 biosensing supported by AI to generate the bioinformatics needed for early stage COVID-19 diagnosis, correlation of viral load with pathogenesis, understanding of pandemic progression, therapy optimization, POC diagnostics, and diseases management in a personalized manner.

Introduction We assessed whether portable photo-electrochemical oxidation (PECO) air purification in the pediatric hospital room setting could improve health outcomes for patients admitted with respiratory distress.  Methods We performed a prospective study evaluating the use of a portable air purifier with PECO technology. The historical control group comprised matched patients. Twenty-seven PECO-equipped portable air filtration devices were placed in the rooms. Clinical endpoints included length of stay in the hospital, length of stay in the intensive care unit (ICU), rates of intubation, non-invasive ventilation, and nebulizer use. Results The mean length of ICU stay was 0.7 days in the pre-intervention period and decreased to 0.4 days post-intervention. The mean length of overall hospitalization reduced by 0.3 days. The rate of non-invasive ventilation use was 77% in the pre-intervention period and decreased to 23% in the post-intervention period. The rate of nebulizer use was 59% in the pre-intervention period and 41% in the post-intervention period. The rate of intubation was 57.1% in the pre-intervention period and 43% in the post-intervention period.  Conclusion  Portable PECO air purification may reduce hospital length of stay, rates of intubation, and need for non-invasive intervention and nebulizers for pediatric patients admitted with respiratory distress., Competing Interests: Dr. Goswami is the inventor of PECO and holds patents in this technology, (Copyright © 2020, Rao et al.)

Background: Photoelectrochemical oxidation (PECO) is a new air purification technology developed to reduce circulating indoor allergens. PECO removes particles as small as 0.1 nm with the destruction of organic matter otherwise not trapped by a traditional filter and removes volatile organic compounds., Objective: We hypothesized that with daily use, the device would reduce user nasal and ocular allergy total symptom scores (TSS) within 4 weeks., Methods: The study was performed among 46 individuals with self-reported allergies using a portable PECO air purifier. Self-reported TSS were calculated at baseline and weekly for 4 weeks following initiation of continuous use of the system. TSS was the sum of total nasal symptom scores (TNSS) and total ocular symptom scores (TOSS) for the week., Results: There was a statistically significant change in overall TSS from baseline to 4 weeks (10.1 at baseline and 4.35 postintervention) resulting in a mean difference of 5.75 (95% confidence interval [CI] 4.32-7.18; P  < .0001). There was a statistically significant change in TNSS from baseline to 4 weeks (6.3 at baseline and 3.04 postintervention) resulting in a mean difference of 3.26 (95% CI 2.33-3.19; P  < .0001). There was a statistically significant change in TOSS from baseline to 4 weeks (3.82 at baseline and 1.3 postintervention) resulting in a mean difference of 2.52 (95% CI 1.74-3.3; P  < .0001)., Conclusion: With the use of PECO air purification technology, TSS, TNSS, and TOSS decreased significantly. These improvements were consistent over the 4-week course of device use.

Metal-insulator-metal tunnel diodes have great potential for use in infrared detection and energy harvesting applications. The quantum based tunneling mechanism of electrons in MIM (metal-insulator-metal) or MIIM (metal-insulator-insulator-metal) diodes can facilitate rectification at THz frequencies. In this study, the required nanometer thin insulating layer (I) in the MIM diode structure was fabricated using the Langmuir-Blodgett technique. The zinc stearate LB film was deposited on Au/Cr coated quartz, FTO, and silicon substrates, and then heat treated by varying the temperature from 100 to 550 °C to obtain nanometer thin ZnO layers. The thin films were characterized by XRD, AFM, FTIR, and cyclic voltammetry methods. The final MIM structure was fabricated by depositing chromium/nickel over the ZnO on Au/Cr film. The current voltage (I-V) characteristics of the diode showed that the conduction mechanism is electron tunneling through the thin insulating layer. The sensitivity of the diodes was as high as 32 V(-1). The diode resistance was ∼80 Ω (at a bias voltage of 0.78 V), and the rectification ratio at that bias point was about 12 (for a voltage swing of ±200 mV). The diode response exhibited significant nonlinearity and high asymmetry at the bias point, very desirable diode performance parameters for IR detection applications.

The characterization of Langmuir-Blodgett thin films of 10,12-pentacosadiynoic acid (PDA) and their use in metal-insulator-metal (MIM) devices were studied. The Langmuir monolayer behavior of the PDA film was studied at the air/water interface using surface tension-area isotherms of polymeric and monomeric PDA. Langmuir-Blodgett (LB, vertical deposition) and Langmuir-Schaefer (LS, horizontal deposition) techniques were used to deposit the PDA film on various substrates (glass, quartz, silicon, and nickel-coated film on glass). The electrochemical, electrical and optical properties of the LB and LS PDA films were studied using cyclic voltammetry, current-voltage characteristics (I-V), and UV-vis and FTIR spectroscopies. Atomic force microscopy measurements were performed in order to analyze the surface morphology and roughness of the films. A MIM tunnel diode was fabricated using a PDA monolayer assembly as the insulating barrier, which was sandwiched between two nickel layers. The precise control of the thickness of the insulating monolayers proved critical for electron tunneling to take place in the MIM structure. The current-voltage characteristics of the MIM diode revealed tunneling behavior in the fabricated Ni-PDA LB film-Ni structures.

Purpose: Ventilator-associated pneumonia (VAP) is a nosocomial infection resulting in significant morbidity and mortality. Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) are pathogens associated with VAP. Silver (Ag) coating of endotracheal tubes (ETTs) reduces bacterial colonization, however titanium dioxide (TiO(2)) coating has not been studied., Methods: Five types of ETT coatings were applied over silica layer: Ag, solgel TiO(2), solgel TiO(2) with Ag, Degussa P25 TiO(2) (Degussa TiO(2)), and Degussa TiO(2) with Ag. After ETTs were incubated with P. aeruginosa or S. aureus; colonization was determined quantitatively., Results: Pseudomonas aeruginosa and S. aureus grew for 5 days on standard ETTs. Compared to standard ETTs, P. aeruginosa growth was significantly inhibited by solgel TiO(2) with Ag at 24 hours, and by Degussa TiO(2) with Ag at 24 and 48 hours after inoculation. No significant difference in S. aureus growth was observed between the control and any of the five coatings for 5 days., Conclusion: In vitro, solgel TiO(2) with Ag and Degussa TiO(2) with Ag both attenuated P. aeruginosa growth, but demonstrated no effect on S. aureus colonization. Further studies using alternative coating and incorporating UV light exposure are needed to identify their potential utility in reducing VAP.

We report for the first time the reversible hydrogen storage behavior at room temperature in polyaniline nanofibers. The rate of hydrogen sorption during the initial run was very rapid and an extended plateau pressure of about 30 bars was obtained from the pressure-composition isotherm profiles of these polyaniline nanofibers. The reversible cycling capacity of approximately 3-4 wt% was demonstrated at room temperature and has been attributed to the unique nanofibrous microstructural and surface properties.

The photocatalytic destruction of methyl orange in aqueous solution has been studied over single crystal ZnO surfaces under UV irradiation. Differences in the apparent reaction rates between the polar surfaces (first order) and the nonpolar ZnO(10-10) surface (zero order) were observed. Reaction rates for different crystallographic orientations showed the highest activity for ZnO(10-10) followed by ZnO(0001)-Zn and the lowest activity for ZnO(000-1)-O surfaces. In addition, the etching of surfaces by photolysis has been studied. For this process, strongly face-dependent behavior was also observed. Possible reasons for the face dependencies are discussed.

TiO(2) photocatalysis with ultraviolet (UV-A) light has proven to be a highly effective process for complete inactivation of airborne microbes. However, the overall efficiency of the technology needs to be improved to make it more attractive as a defense against bio-terrorism. The present research investigates the enhancement in the rate of destruction of bacterial spores on metal (aluminum) and fabric (polyester) substrates with metal (silver)-doped titanium dioxide and compares it to conventional photocatalysis (TiO(2) P25/+UV-A) and UV-A photolysis. Bacillus cereus bacterial spores were used as an index to demonstrate the enhanced disinfection efficiency. The results indicate complete inactivation of B. cereus spores with the enhanced photocatalyst. The enhanced spore destruction rate may be attributed to the highly oxidizing radicals generated by the doped TiO(2).