Described herein are apparatuses and methods for the processing and/or measurements of chemical or biochemical samples on a digital microfluidic device. Also described are methods to configure and operate the modules for efficient processing and measurements of the samples on the device. The apparatus can be used in applications such as DNA/RNA/protein/cell concentration/purification, real-time PCR, isothermal amplification, immunoassay, cell-based assay, library preparation for NGS sequencing, etc.

Methods for selectively adding one or more reagents are provided. In certain aspects, the methods include selectively merging one or more droplets of a plurality of droplets with one or more droplets of a plurality of reagent droplets based on detection of a property. Systems, devices and kits for practicing the subject methods are also provided. The subject disclosure may find use in a wide variety of applications, such as increasing the accuracy and/or efficiency of single-cell sequencing, detection of cancer or other diseases, monitoring disease progression, analyzing the DNA or RNA content of cells, and other applications in which it is desired to detect and/or quantify specific target cells.

An integrated semiconductor device for manipulating and processing bio-entity samples and methods are described. The device includes a lower substrate, at least one optical signal conduit disposed on the lower substrate, at least one cap bonding pad disposed on the lower substrate, a cap configured to form a capped area, and disposed on the at least one cap bonding pad, a fluidic channel, wherein a first side of the fluidic channel is formed on the lower substrate and a second side of the fluidic channel is formed on the cap, a photosensor array coupled to sensor control circuitry, and logic circuitry coupled to the fluidic control circuitry, and the sensor control circuitry.

A microfluidic apparatus is provided that includes a thermoelectrically-activated pixel array, a microfluidic chip, and control circuitry. The pixel array may include a plurality of thermal pixels, with each thermal pixel including a thermoelectric device. The microfluidic chip may include a microfluidic channel disposed adjacent to the thermal pixels such that thermal energy generated by the thermal pixels is received by the microfluidic channel to form a localized spot within the microfluidic channel corresponding to each thermal pixel. The control circuitry may be electrically coupled to each of the thermal pixels and configured to control the thermal energy being generated by each thermal pixel to control a temperature at each localized spot within the microfluidic channel.

Provided herein are systems, methods, and articles of manufacture for collecting and merging two different size droplets using a substrate comprising a plurality of trapping sites. In certain embodiments, provided herein are systems composed of a plurality of larger droplets and smaller droplets and a substrate comprising a plurality of trapping sites where each trapping site is configured to trap only one of the larger droplets and only one of the smaller droplets when the larger droplet is already present at the trapping site. In particular embodiments, the larger and/or smaller droplets are sorted prior to being contacted with the substrate to ensure they contain the desired component (e.g., cell or barcoded bead). In other embodiments, each trapping site is composed of one or multiple fluidically linked capture wells. In some embodiments, collected larger and smaller droplets are merged (e.g., via a demulsifier or electricity).

The present disclosure provides a microfluidic chip and a droplet separation method, and belongs to the field of biological chip technology. The microfluidic chip includes a first liquid tank and a second liquid tank opposite to each other and a channel layer therebetween. The channel layer includes a plurality of microfluidic channels separated from each other, first ends of the microfluidic channels are communicated with the first liquid tank, and second ends are communicated with the second liquid tank. The first liquid tank contains sample solution to be detected, and the second liquid tank contains encapsulating liquid. The sample solution to be detected entering the first liquid tank may be separated into a plurality of sample droplets through the microfluidic channels, the separated sample droplets enter the second liquid tank, so that the encapsulating liquid is encapsulated on a surface of each of the plurality of sample droplets.

A cartridge for use with an instrument to perform measurement of a fluid, including a digital microfluidics substrate comprising a plurality of electrowetting electrodes operative to perform droplet operations on a liquid droplet in a droplet operations gap; a top plate separated from the digital microfluidics substrate to form a droplet operations gap and comprising openings for injecting liquids into the droplet operations gap; a fiber assembly comprising a fiber optic probe projecting into the droplet operations gap and having a sensing end situated in proximity with one or more of the electrowetting electrodes.

Described herein are digital microfluidic (DMF) devices and corresponding methods for managing reagent solution evaporation during a reaction. Reactions on the DMF devices described here are performed in an air or gas matrix. The DMF devices include a means for performing reactions at different temperatures. To address the issue of evaporation of the reaction droplet especially when the reaction is performed at higher temperatures, a means for introducing a replenishing droplet has been incorporated into the DMF device. A replenishing droplet is introduced every time when it has been determined that the reaction droplet has fallen below a threshold volume. Detection and monitoring of the reaction droplet may be through visual, optical, fluorescence, colorimetric, and/or electrical means.

Digital microfluidic (DMF) apparatuses and methods for optically-induced heating and manipulating droplets are described herein. DMF apparatuses employing photonic heating as described herein provide radical simplification of routing droplets/reagents in complex, multistep protocols and/or highly plexed workflows.

Methods for detecting target analytes utilizing an array of wells are advantageous for detection of low concentrations of target analytes. Use of an array of wells requires sealing of the wells. The methods provided herein utilize digital microfluidics to seal wells of an array with a fluid that is immiscible with the aqueous liquid present in the wells to prevent evaporation and contamination of the aqueous fluid during analysis of signals from the wells. The disclosed method include generating a biphasic droplet composed of the immiscible fluid and an aqueous fluid. The immiscible fluid present in the biphasic droplet is moved over the array of wells to seal the wells by electrically actuating the aqueous fluid present in the biphasic droplet which in turn pulls the immiscible fluid.