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Accurate and rapid point-of-care tissue and microbiome sampling is critical for early detection of cancers and infectious diseases and often result in effective early intervention and prevention of disease spread. In particular, the low prevalence of Barrett's and gastric premalignancy in the Western world makes population-based endoscopic screening unfeasible and cost-ineffective. Herein, we report a method that may be useful for prescreening the general population in a minimally invasive way using a swallowable, re-expandable, ultra-absorbable, and retrievable nanofiber cuboid and sphere produced by electrospinning, gas-foaming, coating, and crosslinking. The water absorption capacity of the cuboid- and sphere-shaped nanofiber objects is shown ∼6000% and ∼2000% of their dry mass. In contrast, unexpanded semicircular and square nanofiber membranes showed500% of their dry mass. Moreover, the swallowable sphere and cuboid were able to collect and release more bacteria, viruses, and cells/tissues from solutions as compared with unexpanded scaffolds. In addition to that, an expanded sphere shows higher cell collection capacity from the esophagus inner wall as compared with the unexpanded nanofiber membrane. Taken together, the nanofiber capsules developed in this study could provide a minimally invasive method of collecting biological samples from the duodenal, gastric, esophagus, and oropharyngeal sites, potentially leading to timely and accurate diagnosis of many diseases. STATEMENT OF SIGNIFICANCE: Recently, minimally invasive technologies have gained much attention in tissue engineering and disease diagnosis. In this study, we engineered a swallowable and retrievable electrospun nanofiber capsule serving as collection device to collect specimens from internal organs in a minimally invasive manner. The sample collection device could be an alternative endoscopy to collect the samples from internal organs like jejunum, stomach, esophagus, and oropharynx without any sedation. The newly engineered nanofiber capsule could be used to collect, bacteria, virus, fluids, and cells from the abovementioned internal organs. In addition, the biocompatible and biodegradable nanofiber capsule on a string could exhibit a great sample collection capacity for the primary screening of Barret Esophagus, acid reflux, SARS-COVID-19, Helicobacter pylori, and gastric cancer.

Liquid metal–elastomer composite is a promising soft conductor for skin-interfaced bioelectronics, soft robots, and others due to its large stretchability, ultrasoftness, high electrical conductivity, and mechanical-electrical decoupling. However, it often suffers from deformation-induced leakage, which can smear skin, deteriorate device performance, and cause circuit shorting. Besides, antimicrobial property is desirable in soft conductors to minimize microbial infections. Here, we report phase separation–based synthesis of porous liquid metal–elastomer composites with high leakage resistance and antimicrobial property, together with large stretchability, tissue-like compliance, high and stable electrical conductivity over deformation, high breathability, and magnetic resonance imaging compatibility. The porous structures can minimize leakage through damping effects and lower percolation thresholds to reduce liquid metal usage. In addition, epsilon polylysine is loaded into elastic matrices during phase separation to provide antimicrobial property. The enabled skin-interfaced bioelectronics can monitor cardiac electrical and mechanical activities and offer electrical stimulations in a mechanically imperceptible and electrically stable manner even during motions.

Background Aerosol transmission of COVID-19 is the subject of ongoing policy debate. Characterizing aerosol produced by people with COVID-19 is critical to understanding the role of aerosols in transmission. Objective We investigated the presence of virus in size-fractioned aerosols from six COVID-19 patients admitted into mixed acuity wards in April of 2020. Methods Size-fractionated aerosol samples and aerosol size distributions were collected from COVID-19 positive patients. Aerosol samples were analyzed for viral RNA, positive samples were cultured in Vero E6 cells. Serial RT-PCR of cells indicated samples where viral replication was likely occurring. Viral presence was also investigated by western blot and transmission electron microscopy (TEM). Results SARS-CoV-2 RNA was detected by rRT-PCR in all samples. Three samples confidently indicated the presence of viral replication, all of which were from collected sub-micron aerosol. Western blot indicated the presence of viral proteins in all but one of these samples, and intact virions were observed by TEM in one sample. Significance Observations of viral replication in the culture of submicron aerosol samples provides additional evidence that airborne transmission of COVID-19 is possible. These results support the use of efficient respiratory protection in both healthcare and by the public to limit transmission.

Following the COVID-19 outbreak, swabs for biological specimen collection were thrust to the forefront of healthcare materials. Swab sample collection and recovery are vital for reducing false negative diagnostic tests, early detection of pathogens, and harvesting DNA from limited biological samples. In this study, we report a new class of nanofiber swabs tipped with hierarchical 3D nanofiber objects produced by expanding electrospun membranes with a solids-of-revolution-inspired gas foaming technique. Nanofiber swabs significantly improve absorption and release of proteins, cells, bacteria, DNA, and viruses from solutions and surfaces. Implementation of nanofiber swabs in SARS-CoV-2 detection reduces the false negative rates at two viral concentrations and identifies SARS-CoV-2 at a 10× lower viral concentration compared to flocked and cotton swabs. The nanofiber swabs show great promise in improving test sensitivity, potentially leading to timely and accurate diagnosis of many diseases.

Introduction As a result of the COVID-19 pandemic and highly contagious nature of SARS-CoV-2, emergency departments (EDs) have been forced to implement new measures and protocols to minimize the spread of the disease within their departments. The primary objective of this study was to determine if the implementation of a designated COVID-19 cohort area (hot zone) within a busy ED mitigated the dissemination of SARS-CoV-2 throughout the rest of the department. Methods In an ED of a tertiary academic medical center, with 64,000 annual visits, an eight room pod was designated for known COVID-19 or individuals with high suspicion for infection. There was a single entry and exit for donning and doffing personal protective equipment (PPE). Health care workers (HCW) changed gowns and gloves between patients, but maintained their N-95 mask and face shield, cleaning the shield with a germicidal wipe between patients. Staffing assignments designated nurses and technicians to remain in this area for 4 h, where physicians regularly moved between the hot zone and rest of the ED. Fifteen surface samples and four air samples were taken to evaluate SARS-CoV-2 contamination levels and the effectiveness of infection control practices. Samples were collected outside of patient rooms in 3 primary ED patient care areas, the reception area, the primary nurses station, inside the cohort area, and the PPE donning and doffing areas immediately adjacent. Samples were recovered and analyzed for the presence of the E gene of SARS-CoV-2 using RT-PCR. Results SARS-CoV-2 was not detected on any surface samples, including in and around the cohort area. All air samples outside the COVID-19 hot zone were negative for SARS-CoV-2, but air samples within the cohort area had a low level of viral contamination. Conclusion A designated COVID-19 cohort area resulted in no air or surface contamination outside of the hot zone, and only minimal air, but no surface contamination, within the hot zone.

As the world recovers from the lockdown imposed by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic, returning to shared indoor spaces is considered a formidable risk. It is now clear that transmission of SARS-CoV-2 is driven by respiratory microdroplets expelled by infected persons, which can become suspended in the air. Several layering technologies are being explored to mitigate indoor transmission in the hopes of re-opening business, schools and transportation systems. Here we coupled the water adsorptive and photocatalytic capacity of novel Metal Organic Frameworks (MOFs) to demonstrate the capture and inactivation of SARS-CoV-2. Discussion is given on the methods of analysis and the differences between the photocatalytic activity of several MOFs, and the difference between MOF induced photocatalysis and ultra violet photolysis of SARS-CoV-2. Our results are intended to provide support to industry looking for alternative methods secure indoor spaces.

Study Objectives: Over 90,000 health care workers worldwide have been infected with SARS-CoV-2 In response to the COVID-19 pandemic, emergency departments (EDs) implemented new measures to minimize the spread of the disease within their patient care areas The primary objective of this study was to determine if SARS-CoV-2 viral particles were present on surfaces or in the air, in a designated COVID-19 cohort area, or ‘hot zone ’ Secondary analysis involved testing for viral particles in others areas of the ED outside of the ‘hot zone ’ Methods: This study took place in the ED of a tertiary academic medical center, with approximately 64,000 annual visits We designated a pod of 8 rooms for known COVID-19 infection or individuals with high suspicion for infection The area consisted of a single entry (Personal protective equipment donning area) and exit (PPE doffing area) Health workers would change gowns and gloves between patients, but maintain their N-95 mask and face shield, after cleaning with a germicidal wipe Fifteen surface samples and four air samples were taken in the ED to evaluate SARS-CoV-2 contamination levels and the effectiveness of infection control practices Samples were collected outside of patient rooms in 3 primary areas, the reception area, the primary nurses station, inside the cohort area, and the PPE donning and doffing areas immediately adjacent The 15 surface samples were collected using 3x3 sterile gauze pads pre-wetted with 3 mL of phosphate buffered saline (PBS), over an approximately 100 cm2 area by wiping in an “S” pattern in 2 directions Stationary air samples were collected using a Sartorius Airport MD8 air sampler operating at 30 liters per minute for 30 minutes onto an 80mm gelatin filter All samples were recovered in sterile PBS, had RNA extracted and were analyzed for the presence of SARS-CoV-2 by RT-PCR targeting the E gene of SARS-CoV-2 Results: SARS-CoV-2 was not detected on any surface samples collected in the ED All air samples outside the COVID-19 hot zone were also negative for SARS-CoV-2 The air samples from inside the cohort area had a low level of viral contamination, but no surface samples in or around the cohort area showed any indication of viral contamination These data suggest that despite having a large influx of COVID-19 patients on the day of sampling, the infection control practices were sufficient to either prevent or eliminate surface contamination The positive air sample from the cohort area suggests that respiratory protection with an N-95 respirator inside the cohort area, even outside of patient rooms is warranted to adequately protect health care providers Conclusion: A designated COVID-19 cohort area resulted in no air or surface contamination outside of the hot zone, and only minimal air, but no surface contamination, within the hot zone