Palo Alto Research Center Inc.

University of California

Jeonggi Seo

Meng H Lean

Ashutosh Kole

Armin R Volkel

Huangpin Ben Hsieh

Nathan W Cheung

Scott J Limb

Luke P Lee

Norine E Chang

Armin Rainer Völkel

Timothy David Sands

Michelle Khine

Kai Melde

Scott Jong Ho Limb

Nitin S Parekh

Cristian Ionescu-Zanetti

H Ben Hsieh

Nitin Parekh

J Alex Chediak

Zhongsheng Luo

Joe Zuback

Adrian Lau

A technique using a curved channel of a spiral device to introduce a centrifugal force upon neutrally buoyant particles flowing in a fluid, e.g. water, to facilitate improved separation of such particles from the fluid is provided. As these neutrally buoyant particles flow through the channel, a tubular pinch effect causes the particles to flow in a tubular band. The introduced centrifugal force perturbs the tubular band (e.g. forces the tubular band to flow in a manner offset from a center of the channel), resulting in an asymmetric inertial migration of the band toward the inner wall of the channel. This allows for focusing and compaction of suspended particulates into a narrow band for extraction. The separation principle contemplated herein implements a balance of the centrifugal and fluidic forces to achieve asymmetric inertial equilibrium near the inner sidewall.

Fluidic device and method for separation of neutrally buoyant particles

A transformational approach to water treatment is provided that incorporates membrane-free filtration with dynamic processing of the fluid to significantly reduce treatment times, chemical cost, land use, and operational overhead. This approach provides hybrid capabilities of filtration, together with chemical treatment, as the water is transported through various spiral stages.

Device and method for dynamic processing in water purification

Fluidic structures for facilitating particle separation in curved or spiral devices are provided. The contemplated systems relate to various fluidic structures, implementations and selected fabrication techniques to realize construction of fluidic separation structures that are of a stacked and/or parallel configuration. These contemplated systems provide for efficient input of fluid to be processed, improved throughput, and, in some variations, adjustable and efficient treatment of output fluid.

Fluidic structures for membraneless particle separation

This invention is based on size and mass separation of suspended particles, including biological matter, which are made to flow in a spiral channel. On the spiral sections, the inward directed transverse pressure field from fluid shear competes with the outward directed centrifugal force to allow for separation of particles. At high velocity, centrifugal force dominates and particles move outward. At low velocities, transverse pressure dominates and the particles move inward. The magnitudes of the two opposing forces depend on flow velocity, particle size, radius of curvature of the spiral section, channel dimensions, and viscosity of the fluid. At the end of the spiral channel, a parallel array of outlets collects separated particles. For any particle size, the required channel dimension is determined by estimating the transit time to reach the side-wall. This time is a function of flow velocity, channel width, viscosity, and radius of curvature. Larger particles may reach the channel wall earlier than the smaller particles which need more time to reach the side wall. Thus a spiral channel may be envisioned by placing multiple outlets along the channel. This technique is inherently scalable over a large size range from sub-millimeter down to 1 &#x3bc;m.

Particle separation and concentration system

Trapping structures are provided for particle separation devices that make use of traveling wave fluid flow. These trapping structures are operative to capture and collect separated particles and present them for extraction. The extraction can be accomplished in conventional manners, such as through the use of suitable sized pipettes.

Trapping structures for a particle separation cell

A method and system for splitting fluid flow in an outlet of a particle separation device is provided. The system may include static or passive mechanisms or subsystems. These mechanisms could also be modular and interchangeable to provide for preset fluid split divisions of 20:80, 30:70, 40:60, 50:50, . . . etc. In other forms of the presently described embodiments, the system is adjustable and variable. In still another form of the presently described embodiments, the system allows for differential pressure control at the outlets to facilitate the flow of varying size particles or particle bands in the respective channels or paths.

Method and apparatus for splitting fluid flow in a membraneless particle separation system

A system to facilitate separation and concentration of particles based on centrifugal force on suspended particles, including biological matter, which are made to flow in a vortex structure is provided. The centrifugal force urges larger particles to collect along outer portions of the vortex flow. Conversely, within a vortex structure, a radial hydrodynamic pressure drop is also amplified to urge smaller particles toward inner portions of the vortex flow. This force created by the pressure can reach magnitudes that encourage a sharp cut-off and improved resolution discrimination between particle sizes. Thus, separated streams of particles can be collected with both increased concentration and purification.

Vortex structure for high throughput continuous flow separation

An improved technique for particle separation is provided. A serpentine structure is utilized in a continuous fluid flow environment to allow for suitable separation of particles to occur in a manner that does not require external application of forces to initiate the separation. The geometry of the serpentine structure and associated forces generated in connection with fluid flow therein suffice.

Serpentine structures for continuous flow particle separations

Method and systems provide improved cell handling in microfluidic systems and devices using lateral cell trapping and methods of fabrication of the same that allow for selective low voltage electroporation and electrofusion.

Method and apparatus for integrated cell handling and measurements

The present invention relates to a functionally integrated microanalytical system for performing fluorescence spectroscopy. A source of fluorescence-exciting radiation, typically a LED, is integrated onto a substrate along with a photodetector and, in some embodiments, an optical filter. A pixel-to-point laser lift-off process is used to effect this component integration. For those cases in which a filter is required, a thin film bandgap filter is typically used, such as CdS or CdSSe(0&#x3c;x&#x3c;1). A disposable microchannel containing the sample and its fluorescent tag is mounted onto the integrated assembly of LED, photodetector and (optionally) filter. This configuration of components allows the microchannel and sample to be readily removed and replaced, facilitating rapid analysis of multiple samples. Multiple LEDS, detectors and filters (if present) can also be integrated onto the same substrate, permitting multiple wavelength analysis of the sample to be performed concurrently.

Growing community of inventors

Albany, CA, United States of America

Jeonggi Seo