Harvard College

Opko Diagnostics, LLC

Max Narovlyansky

George M Whitesides

Vincent Linder

Samuel K Sia

Adam Carlyn Siegel

Xin Chen

Andres W Martinez

Michal Lahav

Adam Winkleman

Zhihong Nie

Raquel Perez-Castillejos

Christian Nijhuis

Emily A Weiss

Leonard N J Rodriguez

The present invention relates generally to microfluidic structures, and more specifically, to microfluidic structures and methods including meandering and wide channels. Microfluidic systems can provide an advantageous environment for performing various reactions and analyses due to a reduction in sample and reagent quantities that are required, a reduction in the size of the operating system, and a decrease in reaction time compared to conventional systems. Unfortunately, the small size of microfluidic channels can sometimes result in difficulty in detecting a species without magnifying optics (such as a microscope or a photomultiplier). A series of tightly packed microchannels, i.e., a meandering region, or a wide channel having a dimension on the order of millimeters, can serve as a solution to this problem by creating a wide measurement area. Although this invention mainly describes the use of meandering and wide channels in heterogeneous immunoassays on a microfluidic chip, this invention could be used for amplifying optical signals for other types of reactions and/or assays.

Fluidic structures including meandering and wide channels

Microfluidic, electrochemical devices are described. The microfluidic, electrochemical device comprises one or more electrode(s) on a substrate and a patterned porous, hydrophilic layer having a fluid-impermeable barrier which substantially permeates the thickness of the porous, hydrophilic layer and defines boundaries of one or more hydrophilic channels within the patterned porous, hydrophilic layer, wherein the hydrophilic channel(s) comprises a hydrophilic region which is in fluidic communication with the electrode(s). In some embodiments, the electrodes comprise a working electrode, a counter electrode, and a reference electrode. In some embodiments, the microfluidic, electrochemical device further comprises a fluid sink. The method of assembling the microfluidic, electrochemical device is described. The method of using the device for electrochemical analysis of one or more analytes is also described.

Microfluidic, electrochemical devices

In one aspect, methods of patterning of thin films of an ionotropic polymer (e.g., poly(acrylic acid)) are provided. These processes can create micron or sub-micron-scale patterns of ionotropic polymers such as cation crosslinked poly(acrylic acid) (CCL-PAA). In one embodiment, patterning may be performed within microfluidic channels by flowing a solution of crosslinking agent (e.g., metal cations such as Ag, Ca, Pd, Al, La, and Ti) that can crosslink a portion of an ionotropic polymer in contact with the solution. In another embodiment, methods of patterning ionotropic polymers involve photolithography. Upon patterning a positive photoresist (e.g., diazonaphthoquinone-novolac resin) on a film of CCL-PAA, the exposed regions of CCL-PAA can be etched by an aqueous solution. Advantageously, the patterned, crosslinked polymer may also serve as both a reactant and a matrix for subsequent chemistry. For example, in some embodiments, the initial crosslinking cation can be exchanged for a second cation that could not be patterned photolithographically. Patterned films of CCL-PAA can also be used to host and template the reduction of metallic cations to metallic nanoparticles, and to fabricate porous, low-k dielectric substrates.

Patterning of ionic polymers

The present invention relates generally to microfluidic structures, and more specifically, to microfluidic structures and methods including meandering and wide channels. Microfluidic systems can provide an advantageous environment for performing various reactions and analysis due to a reduction in sample and reagent quantities that are required, a reduction in the size of the operating system, and a decrease in reaction time compared to conventional systems. Unfortunately, the small size of microfluidic channels can sometimes result in difficulty in detecting a species without magnifying optics (such as a microscope or a photomultiplier). A series of tightly packed microchannels, i.e., a meandering region, or a wide channel having a dimension on the order of millimeters, can serve as a solution to this problem by creating a wide measurement area. Although this invention mainly describes the use of meandering and wide channels in heterogeneous immunoassays on a microfluidic chip, this invention could be used for amplifying optical signals for other types of reactions and/or assays.

Growing community of inventors

Cambridge, MA, United States of America

Max Narovlyansky