Described is a device and method for facilitating the determination of the solubility and dissolution properties of chemical compounds in various solvents. The device uses submilliliter quantities of a solvent and correspondingly small amounts of the chemical compound. The device enables solubility measurements to be made on small amounts of chemical compounds, and enables multiple sampling for generating dissolution profiles. The device includes a housing having first chamber in fluid communica...

This invention relates to a metal ion specific capacitance sensor with exceptional sensitivity and wide operating range. It is versatile because different kinds of recognition elements can be immobilized directly in a self-assembling monolayer substantially completely covering the surface of the measuring noble metal electrode. The electrode then becomes selective to those metal ions in the solution that show affinity to the recognition element on the surface. Compared to previously described el...

A diagnostic system for monitoring catalyst performance in an exhaust system comprises a plurality of treatment devices catalytically treating an exhaust gas stream, and a plurality of gas sensors for monitoring the catalyst performance of the treatment devices to determine when sulfur poisoning occurs. An on-board diagnostic system receives signals from the gas sensors, and, based upon response time differentials between sensors, determines whether the treatment devices are experiencing sulfur ...

A sample presentation device, with a surface-bound complex including at least one molecule which chemically modifies a biomolecule, is prepared and exposed to a biomolecule. The molecular weights of the chemically modified biomolecule is then determined by mass spectrometry.

A method for detecting local shear stress values using molecular rotors that allows for an extremely sensitive determination of a shear stress field or a flow field, even at very low flow rates. In one embodiment, molecular rotors may be adhered to a fiber optic probe or other solid surface, and the fluorescence emission of those molecular rotors may be probed at a location of the fiber optic probe tip or other solid surface. In another preferred embodiment, rotors may be adhered to another soli...

A method of measuring an analyte in a biological fluid comprises applying an excitation signal having a DC component and an AC component. The AC and DC responses are measured; a corrected DC response is determined using the AC response; and a concentration of the analyte is determined based upon the corrected DC response. Other methods and devices are disclosed.

A highly selective and sensitive of a carbonic anhydrase-based method for measurement of zinc ion by an excitation ratiometric format based on resonance energy transfer: i.e., where the zinc ion level is transduced as the ratio of fluorescence intensities excited at two different excitation wavelengths, is provided. The method can be used very well in a fluorescence microscopy format. A detection limit of about 10 pM in zinc buffered systems, a ten to one thousand-fold improvement on the Fura in...

The present invention relates to a method for determining the condition of a biological fluid by recording the IR spectrum of a sample of the biological fluid. To this end, the biological fluid can be examined in its native form. The method of the invention is usable, for example, for detecting pathological conditions in organisms.

A method of directed automated analysis of a plurality of analytes of a process solution includes providing a sample of the process solution containing a plurality of the analytes, admixing an enriched isotope spike for each of the plurality of analytes to be analyzed with the process solution sample thereby effecting admixture of the enriched ratio of isotopes with the naturally occurring ratio of each analyte to be analyzed, creating ions from the spikes, introducing the ions into a mass spect...

The invention relates to a centrifuge apparatus with a built-in sample tube reader and methods for rapidly obtaining measurements of creamatocrit, fat content and/or energy (caloric) content from low-volume fresh and frozen milk specimens.