This invention features systems and methods for the detection of analytes, and their use in the treatment and diagnosis of disease.

Disclosed is a method of measuring tacrolimus levels in a subject. In exemplary embodiments, the method comprises the steps of: collecting oral fluid from the subject; homogenizing the oral fluid; combining the homogenized oral fluid with a precipitating solvent; separating oral fluid components on a liquid chromatography column by gradient elution with a mixture of a solvent A and a solvent B, wherein the solvent A is about 2 mM ammonium acetate/0.1% (v/v) formic acid in water and solvent B is about 2 mM ammonium acetate/0.1% (v/v) formic acid in MeOH and wherein the amount of solvent B is increased from about 50% (v/v) to about 98% (v/v); and determining amount of tacrolimus in the oral fluid by mass spectrometry.

Methods are described for determining the amount of metabolites of leflunomide in a sample. More specifically, mass spectrometric methods are described for detecting and quantifying teriflunomide in a sample.

Provided herein are methods for preventing or treating post-traumatic stress disorder (PTSD) in a subject, the methods including: administering an agent which inhibits formation of a glucocorticoid receptor (GR)-FK506 Binding Protein 51 (FKBP51) complex (GR-FKBP51 complex), or which disrupts already formed GR-FKBP51 complex, to the subject; thereby reducing a level of GR-FKBP51 complex in the subject and preventing or treating the PTSD. Also provided are methods for diagnosing a subject as having, or being at risk of developing, a PTSD, the methods including steps of: measuring a level of a GR-FKBP51 complex in the subject; comparing the measured level to a reference level of a non-PTSD condition; and identifying the subject as having, or being at risk of developing, PTSD where the measured level is elevated relative to the reference level. Agents, compositions, and/or kits for the diagnosis and/or treatment of PTSD are also described.

Devices and methods to perform a competitive immunoassay are disclosed. In some embodiments, the competitive immunoassay is for the detection of tacrolimus. The devices comprise a plurality of layers optionally made of cellulose-based material, wherein the plurality of layers comprises at least one read-out layer displaying a colorimetric readout of the device to indicate the result of the test to the user.

Provided herein are methods for accommodating for sample matrix effects in light measurement assays. A selected amount of a light emitting material is added to a sample, and the light output from the sample is measured. By using an algorithm based on the known light emitting material amount and the measured light output, a correction factor for the assay of the sample is determined. The correction factor can be used to adjust subsequent light output measurements of other samples recorded using the assay.

Systems, apparatuses, kits, and methods for purification and analysis of analytes having a broad range of hydrophobicities by liquid chromatography-mass spectrometry (LC-MS). Using one set of liquid chromatography columns, one set of mobile phase buffers, and, optionally, a single ionization method (e.g., electrospray ionization), a wide range of analytes can be purified and analyzed on a liquid chromatography-mass spectrometry (LC-MS) system. LC-MS purification and analysis of analytes having a broad range of partition coefficients is accomplished by selecting LC run parameters and MS system parameters that are particular to different classes of analytes without having to make column or buffer changes or any other hardware configuration changes to the LC-MS system. The methods, systems, and kits described herein provide for substantially increased speed/throughput and ease of use for a wide range analytes with essentially no compromise in specificity for individual analytes relative to previously described methods.

Methods are described for determining the amount of metabolites of leflunomide in a sample. More specifically, mass spectrometric methods are described for detecting and quantifying teriflunomide in a sample.

The present invention relates to a novel use of regulatory T cell-specific surface protein Lrig-1, and more specifically to an immunosuppressive agent comprising siRNA which inhibits the expression of surface protein Lrig-1. In addition, the invention relates to a method for screening an immunosuppressive agent which inhibits proteins of Lrig-1 or genes encoding the proteins. As a result, an immunosuppressive agent with low side effects and high specificity can be developed.

The present invention relates functional ligands to target molecules, particularly to functional nucleic acids and modifications thereof, and to methods for simultaneously generating, for example, numerous different functional biomolecules, particularly to methods for generating numerous different functional nucleic acids against multiple target molecules simultaneously. The present invention further relates to functional ligands which bind with affinity to target molecules, such as opioids and opioid derivatives.