Waters Investments Limited

Waters Technologies Corporation

Michael J Leveille

Joseph M DeLuca

Anthony C Gilby

Robert Karol

The invention features an optical medium for calibrating UV absorbance detectors, methods for making such an optical medium, and methods for calibrating UV absorbance detectors using such a medium. The optical calibration medium includes a gel-sol silica glass monolith with a rare-earth dopant therein. The rare-earth dopant exhibits at least one spectral feature in at least the far UV range. The constituents of the gel-sol silica glass monolith are selected so the rare-earth doped sol-gel glass monolith exhibits a transmittance in the far UV range so each distinct spectral feature of the rare-earth dopant in the far UV range is discernable. The transmittance in a particular embodiment is at least about 50% at about 250 nm. The rare earth materials selected for use as dopants are those exhibiting a wide range of spectral features, preferably over a range from about 190 nm to about 700 nm and more particularly exhibit at least one distinct spectral feature in the range from about 190 nm to about 300 nm. In a specific embodiment, the rare-earth dopant includes atoms of erbium, having spectral features in a range from about 190 nm to about 650 nm and a distinguishable far UV spectral feature at about 257 nm.

Calibration medium for wavelength calibration of U.V. absorbance detectors and methods for calibration

A photometric measurement flow cell having measurement path-lengths that can be adjusted down to less than 0.1 mm. The measurement path-length is controlled by both a common flow cell body and the dimensional parameters of a stepped sealing optical element. The stepped optical element includes a stem portion that can be made in various lengths to create a family flow cell measurement path-lengths. The replacement of one stepped element with another having a different stem length within the flow cell creates a reliable method to adjust the measured path-length of the flow cell.

Approach to short measurement path-length flow cells

A chromatographic flow cell having the capacity to handle fluid flow from one or more chromatographic systems, at widely varying flow rates without the need to change flow cells or detectors. The flow cell itself acts as a tee where two or more fluidic inlet lines intersect with a common inlet channel. The common inlet channel is configured so that the diameter and length minimizes the total volume, unswept volume, bandspreading, and backpressure. The common outlet channel, inlet lines and the outlet line are sized to provide for adequate fluidic handling at the varied flow rates.

Multiple input flow cell with single fluid path

The invention features an optical medium for calibrating UV absorbance detectors, methods for making such an optical medium, and methods for calibrating UV absorbance detectors using such a medium. The optical calibration medium includes a gel-sol silica glass monolith with a rare-earth dopant therein. The rare-earth dopant exhibits at least one spectral feature in at least the far UV range. The constituents of the gel-sol silica glass monolith are selected so the rare-earth doped sol-gel glass monolith exhibits a transmittance in the far UV range so each distinct spectral feature of the rare-earth dopant in the far UV range is discernable.

Embodiments of the present invention feature devices and methods for analyzing the absorbance spectra of a sample, and a method of making such device. The device comprises a housing having an exterior surface and an interior surface. The interior surface defines a chamber having an input opening and an exit opening defined by rims. The input opening has a first geometric shape and the exit opening has a second geometric shape. Any point about the rim at the input end can be connected by a straight line to any point on the rim of the exit end. The interior surface end of the chamber corresponds to the sum of these lines from the rim of the input opening, to the rim of the exit opening.

Growing community of inventors

Northbridge, MA, United States of America

Michael J Leveille