Philip Y. Paik

Bio: Philip Y. Paik is an academic researcher from Research Triangle Park. The author has contributed to research in topics: Microactuator & Electrowetting. The author has an hindex of 24, co-authored 32 publications receiving 2349 citations. Previous affiliations of Philip Y. Paik include Duke University & United States Department of Energy Office of Science.

Methods and apparatus for manipulating droplets by electrowetting-based techniques

Abstract: An apparatus is provided for manipulating droplets The apparatus is a single-sided electrode design in which all conductive elements are contained on one surface on which droplets are manipulated An additional surface can be provided parallel with the first surface for the purpose of containing the droplets to be manipulated Droplets are manipulated by performing electrowetting-based techniques in which electrodes contained on or embedded in the first surface are sequentially energized and de-energized in a controlled manner The apparatus enables a number of droplet manipulation processes, including merging and mixing two droplets together, splitting a droplet into two or more droplets, sampling a continuous liquid flow by forming from the flow individually controllable droplets, and iterative binary or digital mixing of droplets to obtain a desired mixing ratio

Apparatus for manipulating droplets by electrowetting-based techniques

Abstract: An apparatus is provided for manipulating droplets The apparatus is a single-sided electrode design in which all conductive elements are contained on one surface on which droplets are manipulated An additional surface can be provided parallel with the first surface for the purpose of containing the droplets to be manipulated Droplets are manipulated by performing electrowetting-based techniques in which electrodes contained on or embedded in the first surface are sequentially energized and de-energized in a controlled manner The apparatus enables a number of droplet manipulation processes, including merging and mixing two droplets together, splitting a droplet into two or more droplets, sampling a continuous liquid flow by forming from the flow individually controllable droplets, and iterative binary or digital mixing of droplets to obtain a desired mixing ratio

Electrowetting-based on-chip sample processing for integrated microfluidics

Abstract: In this work, results and data are reported on key aspects of sample processing protocols performed on-chip in a digital microfluidic lab-on-a-chip We report the results of experiments on aspects of sample processing, including on-chip preconcentration and dilution, on-chip sample injection or dispensing, and sample mixing It is shown that high speed transport and mixing of analytes and reagents can be performed using biological solutions without system contamination

Droplet-based biochemistry

Abstract: The present invention relates to a droplet microactuator and to systems, apparatuses and methods employing the droplet microactuator for executing various protocols using discrete droplets. The invention includes a droplet microactuator or droplet microactuator system having one or more input reservoirs loaded with reagents for conducting biochemical reactions, such as the reagents described for use in nucleic acid amplification protocols, affinity-based assay protocols, sequencing protocols, and protocols for analyses of biological fluids.

Droplet-based nucleic acid amplification device, system, and method

Abstract: The present invention relates to a droplet-based nucleic acid amplification device, system, and method. According to one embodiment, a droplet microactuator is provided and includes: (a) a substrate comprising electrodes for conducting droplet operations; and (b) one or more temperature control means arranged in proximity with one or more of the electrodes for heating and/or cooling a region of the droplet microactuator and arranged such that a droplet can be transported on the electrodes into the region for heating.

Digital microfluidics: is a true lab-on-a-chip possible?

Abstract: The suitability of electrowetting-on-dielectric (EWD) microfluidics for true lab-on-a-chip applications is discussed. The wide diversity in biomedical applications can be parsed into manageable components and assembled into architecture that requires the advantages of being programmable, reconfigurable, and reusable. This capability opens the possibility of handling all of the protocols that a given laboratory application or a class of applications would require. And, it provides a path toward realizing the true lab-on-a-chip. However, this capability can only be realized with a complete set of elemental fluidic components that support all of the required fluidic operations. Architectural choices are described along with the realization of various biomedical fluidic functions implemented in on-chip electrowetting operations. The current status of this EWD toolkit is discussed. However, the question remains: which applications can be performed on a digital microfluidic platform? And, are there other advantages offered by electrowetting technology, such as the programming of different fluidic functions on a common platform (reconfigurability)? To understand the opportunities and limitations of EWD microfluidics, this paper looks at the development of lab-on-chip applications in a hierarchical approach. Diverse applications in biotechnology, for example, will serve as the basis for the requirements for electrowetting devices. These applications drive a set of biomedical fluidic functions required to perform an application, such as cell lysing, molecular separation, or analysis. In turn, each fluidic function encompasses a set of elemental operations, such as transport, mixing, or dispensing. These elemental operations are performed on an elemental set of components, such as electrode arrays, separation columns, or reservoirs. Examples of the incorporation of these principles in complex biomedical applications are described.

Rapid droplet mixers for digital microfluidic systems.

Abstract: The mixing of analytes and reagents for a biological or chemical lab-on-a-chip is an important, yet difficult, microfluidic operation. As volumes approach the sub-nanoliter regime, the mixing of liquids is hindered by laminar flow conditions. An electrowetting-based linear-array droplet mixer has previously been reported. However, fixed geometric parameters and the presence of flow reversibility have prevented even faster droplet mixing times. In this paper, we study the effects of varying droplet aspect ratios (height ∶ diameter) on linear-array droplet mixers, and propose mixing strategies applicable for both high and low aspect ratio systems. An optimal aspect ratio for four electrode linear-array mixing was found to be 0.4, with a mixing time of 4.6 seconds. Mixing times were further reduced at this ratio to less than three seconds using a two-dimensional array mixer, which eliminates the effects of flow reversibility. For lower aspect ratio (≤0.2) systems, we present a split-and-merge mixer that takes advantage of the ability to perform droplet splitting at these ratios, resulting in a mixing time of less than two seconds.

Light emitting device package

Abstract: A light-emitting device package including: a package main body including a cavity and a lead frame including a mounting portion disposed in the cavity and a plurality of terminal portions; a light-emitting device chip mounted on the mounting portion; a plurality of bonding wires for electrically connecting the plurality of terminal portions and the light-emitting device chip; a light-transmitting encapsulation layer filled in the cavity; and a light-transmitting cap member disposed in the cavity and blocking the encapsulation layer to contact the plurality of bonding wires.

Electrowetting-based droplet mixers for microfluidic systems

Abstract: Mixing of analytes and reagents is a critical step in realizing a lab-on-a-chip. However, mixing of liquids is very difficult in continuous flow microfluidics due to laminar flow conditions. An alternative mixing strategy is presented based on the discretization of liquids into droplets and further manipulation of those droplets by electrowetting. The interfacial tensions of the droplets are controlled with the application of voltage. The droplets act as virtual mixing chambers, and mixing occurs by transporting the droplet across an electrode array. We also present an improved method for visualization of mixing where the top and side views of mixing are simultaneously observed. Microliters of liquid droplets are mixed in less than five seconds, which is an order of magnitude improvement in reported mixing times of droplets. Flow reversibility hinders the process of mixing during linear droplet motion. This mixing process is not physically confined and can be dynamically reconfigured to any location on the chip to improve the throughput of the lab-on-a-chip.