Litmus Concepts, Inc.

Quidel Corporation

Terrence J Andreasen

Paul J Lawrence

Aulena Churhuri

Aulena Chaudhuri

Mark A Hughes

David R Shockey

Robert Pena

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

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

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

The presence of an enzymatically active hydrolase in a fluid sample is detected by contacting the sample with a solid-phase conjugate which is susceptible to cleavage by the hydrolase, and simultaneously or shortly thereafter, contacting the sample with an indicator which undergoes a detectable change upon the action of a reporter group. The reporter group is part of the conjugate and is liberated from it either partly or entirely by the action of the hydrolase. The indicator is susceptible to action by the reporter group only upon decoupling of the reporter group from the remainder of the conjugate, the decoupling occurring either in part or entirely upon action of the hydrolase. Also provided by this invention are various forms of a dry, self-contained test device which contains the conjugate described above plus the indicator and all other reagents and components necessary to achieve a detectable indication of the presence or absence of a catalytically active hydrolase. Preferred embodiments of the device also contain positive and negative controls.

Assay for proline iminopeptidase and other hydrolytic activities

Methods of assaying the presence of enzymatically active hydrolases (i.e., hydrolytic enzymes) in a sample or specimen are disclosed. In particular, a method of detecting candidiasis by assaying for the presence of enzymatically active aspartic protease in a sample is provided. In these methods, a sample or specimen is contacted with a solid support. The solid support with which the sample is contacted has a reporter enzyme (i.e., a signal generating enzyme) immobilized thereon. The reporter enzyme is immobilized on the solid support in a manner such that it is released from the solid support upon action of the enzymatically active hydrolase if the enzymatically active hydrolase is, in fact, present in the sample. The sample after having been contacted with the solid support is combined with an indicator. The indicator is any chemical species which is susceptible to a detectable change, usually a change in color, upon action of the reporter enzyme. A detectable change in the indicator is an indication that the enzymatically active hydrolase is present in the sample. Moreover, the presence of an enzymatically active hydrolase in a sample may indicate the presence of a particular pathogen or disease state such as, for example, candidiasis. In addition to the methods of assaying for the presence of enzymatically active aspartic protease and other hydrolytic enzymes, a dry, self-contained test device for assaying for the presence of an enzymatically active hydrolase in a sample is disclosed. In particular, a dry, self-contained test device for testing a sample for the presence of candidiasis by assaying for the presence of enzymatically active aspartic protease is also disclosed. These test devices combine 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 whose presence is being detected in the sample, and preferred embodiments contain positive and negative controls as well.

Growing community of inventors

San Jose, CA, United States of America

Terrence J Andreasen