The present invention provides novel methods of magnetically labeling a bacterial cell by contacting the call with an affinity ligand and subsequently contacting the cell with a magnetic agent, where the affinity ligand and magnetic agent include bioorthogonally reactive groups that can react with each other to form a covalent bond. Compounds, compositions, kits and applications of the method are also described.

We disclose a drug tracking system and method of use which may be used to screen a subject's bodily waste in order to assess whether the subject has consumed a drug. The system includes a drug composition which is tagged with at least one artificial sweetener that may be detected in the subject's bodily waste. The subject may consume the tagged drug and a user may obtain a sample of the subject's bodily waste. The bodily waste sample may be analyzed to detect the artificial sweetener or its metabolite. In some embodiments, the result of the analysis of bodily waste may be entered into a database, compared to standards that comprises analyses of a plurality of drug tags, and the identity of the drug tag, and consequently the drug composition, determined.

The present invention concerns a method for capturing and barcoding nucleic acid from single cells, a plurality of microfluidic droplets and a method for preparing said plurality of microfluidic droplets.

The invention provides a method, apparatus and system for separating blood and other types of cellular components, and can be combined with holographic optical trapping manipulation or other forms of optical tweezing. One of the exemplary methods includes providing a first flow having a plurality of blood components; providing a second flow; contacting the first flow with the second flow to provide a first separation region; and differentially sedimenting a first blood cellular component of the plurality of blood components into the second flow while concurrently maintaining a second blood cellular component of the plurality of blood components in the first flow. The second flow having the first blood cellular component is then differentially removed from the first flow having the second blood cellular component. Holographic optical traps may also be utilized in conjunction with the various flows to move selected components from one flow to another, as part of or in addition to a separation stage.

We disclose a method of using taggants to assess how and to what extent a drug in a drug composition that a user has consumed has decayed in response to storage conditions and time. The taggants may decay in response to environmental conditions which cause different drugs to lose their efficacy. These environmental conditions may include light, temperature, oxidation, moisture, and age. The taggants may be detected in biological samples, including urine and feces. By identifying the taggants, the drug composition and other information relating to the drug may be identified. Additionally, quantification of the different taggants may be used to determine whether the drug in the drug composition has been exposed to environmental conditions which may reduce its efficacy.

The present disclosure relates to compositions and methodology for revealing binding sites between proteins, proteins and nucleic acids, or proteins and small molecules. The disclosure provides rapid and direct positive identification and sequencing of the contact region between such molecules, and can be applied to individual interacting pairs, as well as large-scale or global interactions.

A method for detecting an analyte concentration of the present invention includes performing a competitive reaction between a first complex and an analyte standard or an analyte sample, so that the first complex may combine with a metal nanoparticle, and a second complex of a control group and a third complex of a sample group are respectively formed. Then, a difference of heat diffusivity of the second complex and the third complex may determine an analyte sample concentration of the sample group is higher or lower than a pre-determined analyte standard concentration of the control group.

The present invention relates to a method for detecting molecules. The method employs: at least two primary antibodies, wherein the first primary antibody binds to a first site on a molecule and the second primary antibody binds to a second site on a molecule, wherein the second site is different from the first site and wherein the first and second primary antibodies are immunologically distinct; at least two secondary antibodies, wherein the first secondary antibody is labelled with a fluorescence resonance energy transfer (FRET) donor and binds to the first primary antibody; and the second secondary antibody is conjugated or fused to an enzyme and binds the second primary antibody, wherein the first secondary antibody does not bind the second primary antibody and the second secondary antibody does not bind the first primary antibody; a conjugate comprising a FRET acceptor and a substrate specific for the enzyme, wherein when the substrate reacts with the enzyme, an activated conjugate forms, which activated conjugate binds to electron rich moieties on a molecular surface adjacent to the enzyme; wherein the method comprises: contacting a sample with the at least two primary antibodies; contacting the sample with the at least two secondary antibodies; performing a wash step; contacting the sample with the conjugate; and detecting any FRET signal generated by the FRET acceptor.

The present disclosure provides, inter alia, genetically encoded recombinant peptide biosensors comprising analyte-binding framework portions and signaling portions, wherein the signaling portions are present within the framework portions at sites or amino acid positions that undergo a conformational change upon interaction of the framework portion with an analyte.

This disclosure comprises devices and methods for determining the identity of individual protein molecules in a complex mixture.