University of Michigan

Optofluidic Bioassay, LLC

Oakland University

Xudong Fan

Maung Kyaw Khaing Oo

Katsuo Kurabayashi

Hongbo Zhu

Yunbo Guo

Girish Kulkarni

Menglian Zhou

Jiwon Lee

Yu-Cheng Chen

Yogesh B Gianchandani

Qiushu Chen

Zhaohui Zhong

Karthik Reddy

Xiangqun Zeng

Xueding Wang

Yu Qin

Ayush Pandey

Robert Nidetz

Wenzhe Zang

Jing Liu

Yuze Sun

Wonsuk Lee

Zhizheng Zhang

Xuzhou Li

Xiaotian Tan

Jinyan She

Maxwell Wei-Hao Li

A gas chromatography device for peak focusing of one or more target analytes is provided that include a chromatographic column with an inlet and an outlet. A stationary phase is deposited inside the chromatographic column and has a positive thickness gradient. The stationary phase extends from the inlet to the outlet and has a first thickness at the inlet of the chromatographic column and a second thickness at the outlet of the chromatographic column. The second thickness is at least about 10% greater than the first thickness. Methods of peak focusing in a gas chromatography device, method of verifying peak focusing in a gas chromatography device and creating a gas chromatography device having a chromatographic column with a positive thickness gradient are also provided.

Chromatographic column having stationary phase thickness gradient

An integrated microfluidic photoionization detector (PID) is provided including a microfluidic ionization chamber a microfluidic ultraviolet radiation chamber that is configured to generate ultraviolet photons. An ultrathin transmissive window is disposed between the microfluidic ionization chamber and the microfluidic ultraviolet radiation chamber that permits the ultraviolet photons to pass from the microfluidic ultraviolet radiation chamber into the microfluidic ionization chamber. Detection systems for one or more VOC analytes are also provided that include a gas chromatography (GC) unit including at least one gas chromatography column and an integrated microfluidic photoionization detector (PID) disposed downstream of the gas chromatography (GC) unit.

Integrated micro-photoionization detector with an ultrathin ultraviolet transmission window

A laser whose emission is modulated by ultrasound is presented. The laser is usually micron-sized. In response to ultrasound modulation, the laser emission increases and decreases. Such a change in emission can be detected by external optical detectors. This type of laser can be used as a new type of imaging modality, in which laser emission in combination with sound waves or ultrasound waves, is used for imaging Laser emission has a much narrower spectral linewidth and stronger intensity than fluorescence and therefore is able to achieve higher sensitivity, whereas sound waves are used to provide a better spatial resolution of the laser emission from the laser. In ultrasound modulated laser based imaging, multiple lasers can be placed inside cells or tissues.

Acoustic modulated lasers

An optofluidic diagnostic system and methods for rapid analyte detections. The system comprises an optofluidic sensor array, a test plate and an optical detection cartridge. The sensor array supports one or more distinct sensor units, each having a reactor section designed to temporarily enter a series of different kinds of wells in the test plate. One kind of well is a sample reservoir that holds reagent solution to be transferred into the reactor section. Another kind of well is a drainage chamber that removes reagent solution from the reactor section. A third kind of well is a colorant reservoir that holds a colorant reagent transferable into a reactor section. Finally, the sensor unit is transferred to the optical detection cartridge where it is placed into an isolation booth during the optical detection process so that its flat observation face is stationed in a viewing window opposite an optical detector lens.

Optofluidic diagnostics system

An assay plate assembly comprising a plurality of microfluidic modules arranged in a rectilinear matrix of rows and columns microfluidic channels. Each microfluidic module has an inlet well leading to a serpentine microfluidic channel that is set at a cant angle. The well is laterally offset from the detection area to avoid optical interference. The geometric center of each detection area is positioned according to ANSI/SLAS standards for well-centers. A drain from each microfluidic channel is located so that it does not interfere with any detection areas. An array of micro-posts are disposed within each microfluidic channel. The micro-posts extend perpendicularly from the top surface of the top plate toward the underside and are equally distributed throughout the entire detection area. The plate assembly provides reduced assay time and sample volume, and increased sensitivity and specificity in biological and chemical assays.

Assay plate and uses thereof

Laser emission based microscope devices and methods of using such devices for detecting laser emissions from a tissue sample are provided. The scanning microscope has first and second reflection surfaces and a scanning cavity holding a stationary tissue sample with at least one fluorophore/lasing energy responsive species. At least a portion of the scanning cavity corresponds to a high quality factor (Q) Fabry-P&#xe9;rot resonator cavity. A lasing pump source directs energy at the scanning cavity while a detector receives and detects emissions generated by the fluorophore(s) or lasing energy responsive species. The second reflection surface and/or the lasing pump source are translatable with respect to the stationary tissue sample for generating a two-dimensional scan of the tissue sample. Methods for detecting multiplexed emissions or quantifying one or more biomarkers in a histological tissue sample, for example for detection and diagnosis of cancer, or other disorders/diseases are provided.

Laser emission based microscope

A multi-modal biosensor system includes a vibrating plate orientated along a plane. An actuator is interfaced with the vibrating plate and operable to vibrate the vibrating plate along the plane. The actuator includes two electrodes rigidly affixed to the vibrating plate. An optical support structure is rigidly affixed to the vibrating plate, and provides an outwardly facing surface to receive a measurement sample. A light source is configured to project light onto the outwardly facing surface of the optical support structure. A light detector is configured to capture light reflected from the outwardly facing surface of the optical support structure. A controller interfaces with the two electrodes and the light detector. The controller operates to detect changes in the vibrating motion of the vibrating plate concurrently with detecting changes in the light captured by the light detector.

Multi-modal biosensor having an acoustic detector with integrated optical interferometry

Electrochemical sensors for the detection of select analytes are provided. The electrochemical sensors include a barrier layer having a substantially uniformed thickness disposed between a sensing layer and an ion exchange membrane. The barrier layer includes a two-dimensional nanomaterial. The barrier layer has a thickness of less than or equal to about 1 nm. The sensing layer has a thickness of less than or equal to about 10 nm. The sensing layer generates ions in response to select analytes. The barrier layer allows the generation ions to pass therethrough and travel into the ion exchange membrane. The barrier layer acts as a physical barrier to contaminants and larger molecules.

Two-dimensional material based ion exchange membrane sensors

The present disclosure provides a method for conducting comprehensive chromatography analysis. Broadly, the method comprises separating a sample in a first chromatographic column to generate a primary stream, which is directed toward a non-modulator switching system comprising at least one micro-switch and at least one valve. The non-modulator switching system is continuously operated to: (a) selectively direct a portion of the primary stream to one of a plurality of thermal injectors and accumulating the portion of the primary stream for a predetermined amount of time; (b) inject the portion of the primary stream into one of a plurality of secondary chromatographic columns; (c) detect one or more analytes in a secondary stream exiting the secondary chromatographic column; and repeat (a)-(c) to selectively direct other portions of the primary stream to other thermal injectors and secondary chromatographic columns until all of the analytes in the sample are detected.

Multi-channel multi-dimensional comprehensive gas chromatography

An assay plate assembly comprising a plurality of microfluidic modules arranged in a rectilinear matrix of rows and columns microfluidic channels. Each microfluidic module has an inlet well leading to a serpentine microfluidic channel that is set at a cant angle. The well is laterally offset from the detection area to avoid optical interference. The geometric center of each detection area is positioned according to ANSI/SLAS standards for well-centers. A drain from each microfluidic channel is located so that it does not interfere with any detection areas. An array of optically-transmissive micro-posts are disposed within each microfluidic channel. The micro-posts extend perpendicularly from the top surface of the top plate toward the underside and are equally distributed throughout the entire detection area. The plate assembly provides reduced assay time and sample volume, and increased sensitivity and specificity in biological and chemical assays.

A discharge ionization current detector for ionizing and detecting a sample component where the sample component is ionized by UV light is provided. The detector includes a UV light source, and a microfluidic channel having a first surface including a conducting or semiconducting material and an opposing second surface including a conducting or semiconducting material, one of the first surface and the second surface being a collection electrode and the other of the first surface and the second surface being a bias electrode, the microfluidic channel being configured to receive a sample component. The microfluidic channel is in fluid communication with the UV light source such that, when activated, UV light from the UV light source can enter the microfluidic channel and ionize the sample component, which releases an electron, and the ionized sample component and electron are detected by the collection and bias electrodes.

Miniaturized discharge photo-ionization detector

A rapid flow-through, highly sensitive microfluidic photoionization detector (PID) which is micro-fabricated directly onto a substrate, such as a conductive silicon wafer, is provided. The microfluidic PID has an ionization chamber volume of less than 9 &#x3bc;L. The microfluidic PID may have a flow through design with a microfluidic channel defines a serpentine pattern on the substrate. The flow through design of the microfluidic PID results in negligible dead volume, thus allowing a shortened response time over existing commercially available designs. Such microfluidic PIDs are particularly useful with gas chromatography (GC), including microGC and multi-dimensional microGC systems. Methods for calibrating PIDs are also provided.

Microfluidic photoionization detector

An improved sensing method is provided for rapid analyte detection. The method includes: applying an AC excitation signal to the channel region of the transistor; applying an AC drive signal to the transistor; delivering an analyte of interest to a channel region of a transistor; and monitoring a mixing current of the excitation signal and the drive signal through the transistor, where a change in the mixing current is indicative of the concentration of the analyte of interest.

Growing community of inventors

Saline, MI, United States of America

Xudong Fan