A reagent composition for releasing vitamin D compounds bound to vitamin D-binding protein, an in vitro method for the detection of a vitamin D compound in which the vitamin D compound is released from vitamin D-binding protein by the use of this reagent composition and the reagent mixture obtained in this manner. The use of the disclosed reagent composition to release vitamin D compounds as well as a kit for detecting a vitamin D compound which contains the reagent composition for releasing vitamin D compounds in addition to common detecting reagents.

The present invention relates to the field of diagnostic methods. Specifically, the present invention contemplates a method for diagnosing heart failure in a subject and a method for monitoring progression or regression of heart failure in a subject. The invention also relates to tools for carrying out the aforementioned methods, such as diagnostic devices.

The invention relates to the detection of vitamin D metabolites. In a particular aspect, the invention relates to methods for detecting derivatized vitamin D metabolites by mass spectrometry.

Provided are methods for determining the amount of estrone in a sample using mass spectrometry. The methods generally involve ionizing estrone in a sample and detecting and quantifying the amount of the ion to determine the amount of estrone in the sample.

Methods for determining the amount of vitamin D compounds in a sample are provided. The methods can employ LC-MS/MS techniques and optionally the use of deuterated internal standards. Methods for diagnosing vitamin D deficiencies are also provided.

An apparatus is provided for sensing an analyte in a fluid. The apparatus includes a fluid collecting device configured to collect the fluid containing the analyte; a fluid input in fluid communication with the fluid collecting device configured to input the fluid containing the analyte into the fluid collecting device, an analyte interactant in fluid communication with the fluid collecting device, wherein the analyte interactant, when contacted by the analyte, reacts to cause a first change in thermal energy within the fluid collecting device; a modulator that causes a second change in thermal energy; a thermal sensing device comprising at least one pyroelectric device thermally coupled to the fluid collecting device to generate a first signal in response to at least one of the first change in thermal energy and the second change in thermal energy; a control device operatively coupled to the thermal sensing device and the modulator that generates a second signal, wherein the second signal comprises information useful in characterizing the analyte. A related method also is disclosed.

Provided are methods of detecting the presence or amount of a vitamin D metabolite in a sample using mass spectrometry. The methods generally directed to ionizing a vitamin D metabolite in a sample and detecting the amount of the ion to determine the presence or amount of the vitamin D metabolite in the sample. Also provided are methods to detect the presence or amount of two or more vitamin D metabolites in a single assay.

Provided are methods of detecting the presence or amount of a vitamin D metabolite in a sample using mass spectrometry. The methods generally directed to ionizing a vitamin D metabolite in a sample and detecting the amount of the ion to determine the presence or amount of the vitamin D metabolite in the sample. Also provided are methods to detect the presence or amount of two or more vitamin D metabolites in a single assay.

An improved qualitative or semi-quantitative diagnostic test for low levels of any analyte, such as hCG, in a biological sample, such as urine. The test comprises of a test device containing reagents for the detection of the monitored analyte and an electronic reader that measures color development at a detection area of the device. The color development is converted to an electronic or digital signal. Improvements were made to the detection process to optimize the detection of a valid fluid front, increase the detection limit without compromising the reliability and accuracy of the test system, and improve the determination of test result validity.

A reagent composition for releasing vitamin D compounds bound to vitamin D-binding protein and an in vitro method for the detection of a vitamin D compound in which the vitamin D compound is released from vitamin D-binding protein by the use of this reagent composition as well as the reagent mixture obtained in this manner. Also disclosed is the use of the reagent compositions to release vitamin D compounds as well as a kit for detecting a vitamin D compound.