The present disclosure an ELISA-based assay that uses a glycosylated polypeptide fragment derived from the SARS-CoV-2 spike protein (Covid-19) receptor binding domain (S1RBD) that has affinity for the extracellular domain of Angiotensin Converting Enzyme 2 (ACE2). The S1RBD polypeptide is generated by expression of an encoding nucleic acid by a human cell expression system resulting in glycosylation of the expressed spike receptor binding domain (S1RBD) protein at least at the N343 N-glycosylation site thereof, and which surprisingly and significantly increases the affinity of the S1RBD for ACE2, provides a significant increase in the sensitivity of the assay compared to other known assays.

Provided herein are methods of identifying a target protein in a tissue sample that include delivering a plurality of probes to a tissue sample, where a probe of the plurality of probes comprises an antibody conjugated to an oligonucleotide having a sequence, where the antibody specifically binds to the target protein in the tissue sample; amplifying the oligonucleotide to generate an amplicon comprising copies of the oligonucleotide; detecting all or a portion of a copy of the oligonucleotide in the amplicon; and using the detected sequence to identify the target protein in the tissue sample.

The invention relates to methods for conducting solid-phase binding assays. One example is an assay method having improved analyte specificity where specificity is limited by the presence of non-specific binding interactions.

Flow apparatuses comprising a separation channel, a downstream flow separator, a detection zone, an observation zone, and a waste channel. The separation channel has first and second flows in contact and allows lateral movement of components between contacting first and second flows. The downstream flow separator is in communication with the separation channel and diverts a part of the first fluid flow, the second fluid flow, or both, from the separation channel. The detection zone comprises a detection channel downstream of and in communication with the flow separator and configured to receive a plurality of diverted flows from the flow separator and a label channel configured to label the diverted flows from the flow separator. The observation zone is configured to record an analytical signal indicative of the quantity and the electrical properties of the component. The waste channel is at the downstream end of the observation zone.

Provided among other things is an indexed library on one or more solid phase supports of a substantial representation of all theoretical peptide combinations having a certain length of 3 to 5 amino acids, or a combination thereof, and being formed with a certain collection of amino acids that numbers as follows:

TABLE-US-00001 # of amino acids in Length collection 3 6 to 18 4 4 to 18 5 4 to 18
the peptides spaced apart from the supports sufficiently such that one or more of the peptides binds an antibody composition substantially more strongly than others.

The present disclosure is based on the surprising and unexpected discovery that a ligand molecule with certain characteristics is able to bind to two protein molecules simultaneously and recruit them to form a transient or stable protein-protein interaction complex. The protein-protein interaction and other cross-domain interactions gained in this process contribute additional stabilization energy to the complex beyond the combination of the binary binding energies, and therefore, largely increase the binding potency of the ligand. Accordingly, the present disclosure provides a Protein-Protein Interaction Inducing Technology (PPIIT), which includes a method to design and identify the tripartite or bifunctional compounds and use such compounds to induce protein-protein interactions in various contexts. The present disclosure also provides a composition for the purpose of inducing protein-protein interactions.

The present disclosure provides a system comprising a communication interface and computer for assigning a label to the biomolecule fingerprint, wherein the label corresponds to a biological state. The present disclosure also provides a sensor arrays for detecting biomolecules and methods of use. In some embodiments, the sensor arrays are capable of determining a disease state in a subject.

The present disclosure provides sensor arrays for detecting biomolecules and methods of use. In some embodiments, the sensor arrays are capable of determining a disease state in a subject.

The present disclosure provides a system comprising a communication interface and computer for assigning a label to the biomolecule fingerprint, wherein the label corresponds to a biological state. The present disclosure also provides a sensor arrays for detecting biomolecules and methods of use. In some embodiments, the sensor arrays are capable of determining a disease state in a subject.

The present disclosure provides a system comprising a communication interface and computer for assigning a label to the biomolecule fingerprint, wherein the label corresponds to a biological state. The present disclosure also provides a sensor arrays for detecting biomolecules and methods of use. In some embodiments, the sensor arrays are capable of determining a disease state in a subject.