Litmus Concepts, Inc.

Quidel Corporation

Smithkline Instruments, Inc.

Other

Smithkline Diagnostics, Inc.

Paul J Lawrence

Terrence J Andreasen

David R Shockey

Peter U Ly

Charles W Townsley

Hans R Boehringer

Paul Lambotte

Bruce L Jacono

Jeremy Jerome

Mark Daquipa

Aulena Chaudhuri

Aulena Churhuri

Mark A Hughes

Michael B Detweiler

Josefina T Baker

Neil H Price

Marian B Buccafurni

Leah P Lawrence

Robert Pena

A test device and method for determining the presence or absence of one or more analytes in a fluid sample, the test device including a support or member bearing a mark thereon, and a matrix or member containing a capture zone. In operation, an observation area in the test device becomes transparent, thereby allowing the user to view a mark that is present on a support that is disposed beneath the observation area. Typically, the mark on the underlying support is configured as a minus (&#x2212;) sign. In the absence of analyte in the sample, the test device presents a negative result as a minus (&#x2212;) signal. In the presence of analyte in the sample, however, the mark operates in concert with a perpendicular test line on the observation area to present a positive result as a plus (+) signal that is visible to the user.

Method for adding an apparent non-signal line to a rapid diagnostic assay

Diagnostic assay device having an apparent non-signal line

The release by trichomonads of a hydrolase that hydrolyzes a narrowly defined class of substrates at a low pH without interference from hydrolases that are unrelated to trichomoniasis is the basis for a selective diagnostic assay for trichomoniasis that measures hydrolysis of any of these substrates by vaginal fluid at a low pH. Selective assays for trichomoniasis are also obtained by removing particulate matter from a sample of vaginal fluid to extract a fraction devoid of particles greater than a selected size, and where desired, combining the extracted fraction with any of certain specified hydrolase inhibitors, then testing the fraction for enzymatic hydrolase activity. These qualities of trichomoniasis are the basis for a series of diagnostic tests and test devices that produce results that are detectable by visual and other means with a high degree of accuracy.

Assays for trichomonal and other hydrolases

Laminated test devices in which positive results are detected by the appearance of a symbol on the surface of the device due to a color change in an indicator in the device are improved by placing the indicator lamina on one side of a light-transmissive substrate sheet and a pigment lamina on the other side, the indicator lamina forming the icon and the pigment lamina forming the background, the pigment being the color of the indicator prior to the color change. This arrangement reduces false positive readings by obscuring the outlines of the symbol prior to the color change. False negative readings are reduced by further changes in the arrangement of the laminae.

Iconic colorimetric test device with reduced susceptibility to false positive and false negative readings

A control device serving as a source of control reagent for a solid-phase analytical test device is disclosed. The analytical test device analyzes a biological sample for the presence of an analyte such as an enzyme or other chemical species or a particular pH range, and registers the presence or absence of the analyte as a detectable change in an indicator. The control device contains a control reagent that produces the same indicator change and that can be transferred to the analytical test device by a sample implement such as a wet swab. The control reagent is present on the control device as a dry lamina or combination of laminae. A positive control reagent on a control device in accordance with this invention mimics the action of the analyte once it is transferred to the analytical test device, while a negative control reagent on the control device mimics the action of a sample that lacks the analyte.

External dried-reagent control for analytical test devices

Reporter enzyme release technology: methods of assaying for the presence of aspartic proteases and other hydrolytic enzyme activities

Tests for elevated pH and volatile amines in aqueous fluids are disclosed, including tests useful in the diagnosis of bacterial vaginosis and in other biological conditions. By using formulated indicators and indicators held in matrices that are permeable to gas but not to liquid, the tests provide clear and sharp transitions detectable by visual or machine-readable device rather than by subjective judgments such as small gradations in color or olfactory determinations. The tests lend themselves readily to iconic readouts of the test indications and to the inclusion of positive and negative controls.

PH and amine test elements and applications to diagnosis of vaginal infections

Tests for elevated pH and volatile amines in aqueous fluids are disclosed, including tests useful in the diagnosis of bacterial vaginosis and in other biological conditions. By using formulated indicators and indicators held in matrices that are permeable to gas but not to liquid, the tests provide clear and sharp transitions detectable by visual or machine-readable means rather than by subjective judgments such as small gradations in color or olfactory determinations. The tests lend themselves readily to iconic readouts of the test indications and to the inclusion of positive and negative controls.

Method of making a pH and amine test element

pH and amine test elements and applications to diagnosis of vaginal

pH and amine test to diagnosis of vaginal infections

pH test elements

PH and amine test elements

A dry, self-contained test device for assaying for the presence of an enzymatically active hydrolase in a sample is disclosed. The test device combines a reporter enzyme immobilized on a solid support, an indicator, and all other reagents and components necessary to achieve a detectable indication of the presence or absence of the enzymatically active hydrolase in the sample. Preferred devices contain positive and negative controls as well.

Test device for assays for hydrolytic enzyme activity

Growing community of inventors

Campbell, CA, United States of America

Paul J Lawrence