3m Innovative Properties Company

Minnesota Mining and Manufacturing Company

Michael G Williams

Peter D Wickert

Phillip Angelo Bolea

Ai-Ping Wei

Gary E Krejcarek

Kurt J Halverson

Raj Rajagopal

Christine A Binsfeld

James H Wicks

Steven M Heilmann

William Bedingham

Mark Kevitt Debe

Clyde D Calhoun

Sailaja Chandrapati

Louis C Haddad

Jean Qiu

Todd W Johnson

James G Berg

Philip D Eitzman

Gary J Drtina

Heather M Webb

Francois Ahimou

Frederick W Hyde

Karen E Hesselroth

Jerald K Rassmussen

A biological sterilization indicator device is provided. The device comprises a body, a plurality of test microorganisms, and an oxygen-modulated first fluorescent sensor. The body comprises a first layer attached to a second layer, forming at least one isolatable microchamber and at least one primary passageway that provides fluidic communication between ambience and the at least one microchamber. The microchamber has an isolated volume of about 0.5 microliters to about 9.5 microliters. The plurality of test microorganisms and the oxygen-modulated first fluorescent sensor are disposed in the microchamber. A method of using the device to determine the effectiveness of a sterilization process is also provided.

Biological sterilization indicator devices and methods of use

A first method comprises using an imaging device to produce a plurality of images of a culture device, analyzing a first image to identify a microorganism colony at a first location, analyzing a second image to identify a gas bubble at a second location, and determining whether the first location is proximate the second location. A second method comprises analyzing an image of a culture device to detect gas bubbles and classifying the gas bubbles according to a size parameter associated with each of the gas bubbles. A third method comprises analyzing a first area of an image of a culture device to detect a first number of gas bubbles, analyzing a second area of the image to detect a second number of gas bubbles, and comparing the first number of gas bubbles to the second number of gas bubbles.

Method of detecting gas-producing microbial colonies

A method of biological assay comprises the steps of providing an enzyme substrate comprising two fluorescence dye groups bound to a flexible peptide, the dye groups being of proximity sufficiently close so as to allow free energy attractions to draw the dyes together to essentially self-quench fluorescence of the dye groups, wherein self quenching of fluorescence of the dye groups is effected by dye dimerization or stacking, and enzymatically cleaving the peptide to release the fluorescence dye groups from dye dimerization or stacking, thereby producing an increase in fluorescence intensity. A protease substrate for use in the method of the invention is also disclosed. This invention finds use in detection and identification of microorganisms, sterilization assurance, pharmaceutical discovery, enzyme assays, immunoassays, and other biological assays.

Fluorogenic protease substrates based on dye-dimerization

Disc assay devices and methods for the detection and enumeration of microorganisms are disclosed. The devices and methods include a plurality of discs attached to a substrate and a reflector on one surface of each of the discs to reflect electromagnetic energy of selected wavelengths after the energy has passed through the disc. The reflector may be useful to improve the accuracy of detection and/or enumeration of target microorganisms on the assay devices. A system for detecting and/or enumerating target microorganisms on disc assay devices is also provided.

Reflective disc assay devices, systems and methods

Thin film culture devices are described that have positioning structures, as well as methods for harvesting cells from colonies on the culture device based on location of colonies on the device relative to the positioning structures. In addition, a computer readable medium encoded with a computer program is described that identifies position of colonies relative to the positioning structures.

Automated imaging and harvesting of colonies on thin film culture devices

Devices for the propagation or storage of microorganisms are described. Generally, the devices include first and second layers that are separable from each other. The first layer includes a gelling agent and microbial growth medium and the second layer comprising a galling agent. The devices further include an indicator and a corresponding inducer, each of which may be included in the first layer, second layer, or both.

Device for propagation and storage of microorganisms

A method for partitioning an aqueous biological liquid sample into discrete microvolumes for detection and enumeration of microorganisms is described. The method involves distributing microvolumes of a sample to a plurality of hydrophilic liquid-retaining zones of a culture device, where each liquid-retaining zone is surrounded by a portion of a hydrophobic &ldquo;land&rdquo; area. Also disclosed are devices for carrying out these methods.

Method and devices for partitioning biological sample liquids into microvolumes

An assay device for detection and enumeration of microorganisms. The device includes absorbent discs on a substrate, an inoculation vehicle to inoculate the discs with sample and an optional coversheet. Methods of use are also disclosed.

Disc assay device with inoculation pad and methods of use

The use of a precipitable dye and a contrast-coloring dye together enhance visualization of plaques in confluent lawns of bacteria in bacteriophage and bacteria assays. A test sample suspected of containing a bacteriophage is combined with bacteria capable of replicating the bacteriophage, and applied to a water-proof surface to form a support for bacterial growth. The support is provided with the contrast-coloring dye and precipitable dye, and nutrients and salts capable of supporting growth of the bacteria. A lawn of bacteria is formed on the support, and plaques detected on the lawn indicate presence of the bacteriophage. The plaques contain a precipitate formed by enzymatic cleavage of the precipitable dye by an enzyme of the bacterial lawn. A similar procedure is used for detecting bacteria, except that a test sample suspected of containing a bacteria is combined with bacteriophage capable of replicating in the bacteria, and plaques detected indicate presence of the bacteria. The bacteriophage and bacteria assays are carried out with a disposable device containing at least one well having a water-proof surface and a depth of about at least 5 millimeters. A hydratable material containing the contrast-coloring dye and precipitable dye is positioned on the surface. The well may contain substantially vertical sides with a removable cover resting on top of the sides.

Method and device for detecting bacteriophage using contrast-coloring

Bacteria are detected in a test sample by contacting the test sample with a bacteriophage that is capable of replicating in the bacteria, adding the resultant sample to a water-proof surface of a support for bacterial growth that contains a contrast-coloring dye and a precipitable dye, forming a bacterial lawn of a bacteria in which the bacteriophage can replicate on the support and detecting plaques on the bacterial lawn as an indication of the presence of the bacteria. The combination of precipitable dye and contrast-coloring dye improves visualization of plaques. A precipitate is formed in plaques by enzymatic cleavage of the precipitable dye by an enzyme of the bacterial lawn. A procedure for detecting bacteriophage is similar to that for detecting bacteria, except that a test sample suspected of containing bacteriophage is combined with bacteria in which the bacteriophage can replicate, and plaques detected indicate presence of the bacteriophage. The bacteria and bacteriophage detections are carried out with a disposable device containing at least one well having a water-proof surface and substantially vertical sides that extend at least 5 millimeters in height from the surface. A hydratable material containing the precipitable dye and the contrast-coloring dye is positioned on the water-proof surface. A removable cover rests on top of the sides of the well.

Growing community of inventors

Vadnais Heights, MN, United States of America

Michael G Williams