The present invention provides compositions and methods of use comprising a stabilized recombinant E glycoprotein comprising a flavivirus E glycoprotein backbone, which comprises amino acid substitutions that stabilize the E glycoprotein in dimer conformation under physiological conditions.

Disclosed are method for determining coronaviruses, in particular to methods in which the determination is performed using lectins adapted to bind coronavirus glycoproteins. Also disclosed are kits to facilitate performing the method.

A rapid testing mechanism for respiratory viral pathogens includes a filter material positioned to capture exhaled breath particles from a respiratory tract. A portion of the filter material is impregnated with a pathogen binding adsorptive reagent. When the exhaled breath particles pass through the filter material the following occurs: when the binding adsorptive reagent reacts, a positive test for respiratory viral pathogens is indicated by the filter material; and when pathogen binding adsorptive reagent does not react, a negative test for respiratory viral pathogens is indicated by the filter material.

Antibodies that bind SARS-CoV Spike protein, SARS-CoV-2 Spike protein, and methods of using same for treating or preventing conditions associated with SARS or COVID-19 and for detecting SARS-CoV or SARS-CoV-2.

A rapid testing mechanism for respiratory viral pathogens includes a filter material positioned to capture exhaled breath particles from a respiratory tract. A portion of the filter material is impregnated with a pathogen binding adsorptive reagent. When the exhaled breath particles pass through the filter material the following occurs: when the binding adsorptive reagent reacts, a positive test for respiratory viral pathogens is indicated by the filter material; and when pathogen binding adsorptive reagent does not react, a negative test for respiratory viral pathogens is indicated by the filter material.

The disclosure provides example devices and methods for making and using the devices for rapid testing for the SARS-CoV-2 virus. The example device includes (a) a substrate coupled to a metal oxide layer, (b) a graphene layer coupled to the metal oxide layer, (c) a chemical or biochemical linker functionalized with the graphene layer, and (d) a plurality of SARS-CoV-2 receptors that are bound to the graphene layer via the chemical or biochemical linker, wherein the plurality of SARS-CoV-2 receptors comprise SARS-CoV-2 spike antibodies or SARS-CoV-2 spike proteins, where the graphene layer is configured to have a first phononic energy, when the plurality of SARS-CoV-2 receptors are unattached to target molecules, and a second phononic energy, when the plurality of SARS-CoV-2 receptors are attached to target molecules.

Certain aspects of the present disclosure generally relate to systems and methods for determining viruses such as coronaviruses. For instance, some aspects are directed to systems and methods for determining viruses using a partitioning system. Within the partitioning system, free RNA or other nucleic acids may preferentially partition into one phase, while intact viruses may be present in the other phase or in both phases. Accordingly, in some cases, free RNA or other nucleic acids may be preferentially removed, e.g., as compared to intact RNA or other nucleic acids present within a virus. In some cases, the phase containing intact viruses can be determined to determine the infectiousness, e.g., of a sample arising from a subject. This may be useful, for example, for distinguishing subjects who are capable of spreading an infection from those who are not infectious.

A system for detecting a target material in a sample. The system includes a sensor, a light source, an image-capturing device, two linear-crossed polarizers including a first polarizer and a second polarizer, and a processing unit. The sensor is configured to place the sample thereon and includes a fabric impregnated with liquid crystals (LCs). The light source is configured to transmit a beam of light through a path passing from the first polarizer, the sensor, and the second polarizer. The image-capturing device is configured to capture an image of a surface of the second polarizer. The image contains a pattern formed by orientations of LCs corresponding to the sample. The processing unit is configured to detect a presence of the target material in the sample by analyzing the captured image.

Provided herein are systems and methods of collecting a biological sample. Samples may be collected using a sample collection apparatus. The sample collection apparatus may be used to store samples for shipping. The sample collection apparatus may be used to store samples for later analysis. The sample collection apparatus may comprise a membrane having one or more test regions for detecting one or more target analytes within the sample. The sample collection apparatus may comprise a membrane having one or more test regions for quantifying one or more target analytes within the sample.

A method for diagnosing hepatitis virus infection or a hepatitis disease condition in a subject based on hepatitis virus-associated biomarkers present on exosomes in a bodily fluid sample from the subject is disclosed. Also disclosed are a method for monitoring the course of a hepatitis virus infection or a hepatitis disease condition in a subject and a method for monitoring effectiveness of treatment to a subject with an anti-hepatitis virus agent based on hepatitis virus-associated biomarkers present on exosomes in bodily fluid samples from the subject, as well as a kit for diagnosing hepatitis virus infection and/or a hepatitis disease condition in a subject based on hepatitis virus-associated biomarkers on exosomes in bodily fluid samples from the subject.