A microfluidic apparatus is provided having one or more sequestration pens configured to isolate one or more target micro-objects by changing the orientation of the microfluidic apparatus with respect to a globally active force, such as gravity. Methods of selectively directing the movements of micro-objects in such a microfluidic apparatus using gravitational forces are also provided. The micro-objects can be biological micro-objects, such as cells, or inanimate micro-objects, such as beads.

A method is provided for transporting a plurality of cells through a flow chamber, wherein the cells are initially immobilized on an internal surface of the flow chamber. The method comprises: selectively releasing the cells from the internal surface of the flow chamber; and flowing liquid through the flow chamber such that the released cells travel with the liquid, thereby transporting the cells through the flow chamber. Cells can be immobilized on or selectively released from the internal surface by applying or removing a trapping potential. The trapping potential can arise from an electric field gradient or an optical field gradient. Alternatively, cells can be selectively released from the surface using photocatalysis. Selective release allows cells to be individually observed or analyzed downstream, and can be based on a signal detected from one or more cells immobilized on the surface.

A apparatus for performing contactless ODEP for separation of CTCs comprises an ODEP device including a first conductive glass and a second conductive glass, the first conductive glass includes a transverse main channel and a longitudinal micro channel perpendicular to the main channel and joining the main channel at a cell separation zone; the first conductive glass includes a first hole and a second hole aligned with two ends of the main channel respectively, and a third hole aligned with one end of the micro channel that is distal to the cell separation zone; a sample receiving member disposed on and aligned with the first hole; an exhaust discharge member disposed on and aligned with the second hole; a target collection member disposed on and aligned with the third hole; and a controller including an optical projection device and an image fetch device.

The invention, provides a method, apparatus and system for separating blood and other types of cellular components, and can be combined with holographic optical trapping manipulation or other forms of optical tweezing. One of the exemplary methods includes providing a first flow having a plurality of blood components; providing a second flow; contacting the first flow with the second flow to provide a first separation region; and differentially sedimenting a first blood cellular component of the plurality of blood components into the second flow while concurrently maintaining a second blood cellular component of the plurality of blood components in the first flow. The second flow having the first blood cellular component is then differentially removed from the first flow having the second blood cellular component. Holographic optical traps may also be utilized in conjunction with the various flows to move selected components from one flow to another, as part of or in addition to a separation stage.

The combined value of integrating optical forces and electrokinetics allows for the pooled separation vectors of each to be applied, providing for separation based on combinations of features such as size, shape, refractive index, charge, charge distribution, charge mobility, permittivity, and deformability. The interplay of these separation vectors allow for the selective manipulation of analytes with a finer degree of variation. Embodiments include methods of method of separating particles in a microfluidic channel using a device comprising a microfluidic channel, a source of laser light focused by an optic into the microfluidic channel, and a source of electrical field operationally connected to the microfluidic channel via electrodes so that the laser light and the electrical field to act jointly on the particles in the microfluidic channel. Other devices and methods are disclosed.

Methods for laser-assisted repositioning of a micro-object and for culturing an attachment-dependent biological cell within a microfluidic device are described herein. Laser illumination is used to controllably create a bubble which repositions the micro-object. Further, methods of culturing an attachment-dependent biological cell are described, where the methods may include laser-assisted repositioning.

A novel Self-Locking Optoelectronic Tweezers (SLOT) for single microparticle manipulation across a large area is provided. DEP forces generated from ring-shape lateral phototransistors are utilized for locking single microparticles or cells in the dark state. The locked microparticles or cells can be selectively released by optically deactivating these locking sites.

A device for sorting bio-particles by image-manipulated electric force includes a first substrate, a second substrate, a fluidic channel, one or more photosensitive layers and an inlet hole. The first substrate has a first conductive electrode, and the second substrate has a second conductive electrode. The second conductive electrode is disposed opposite the first conductive electrode. The fluidic channel is disposed between the first conductive electrode and the second conductive electrode. The photosensitive layer is conformally disposed on at least one of the surfaces of the first conductive electrode and the second conductive electrode. The inlet hole is disposed in the first conductive electrode and the first substrate, where the inlet hole includes a first opening close to the fluidic channel and a second opening away from the fluidic channel, and the surface area of the first opening is greater than the surface area of the second opening.

A fractionation system comprising means for forming a three dimensional optical lattice that is operable to separate particles that have different physical characteristics. Preferably, the wells of the optical lattice are interlinked. For example, the wells may be linked in such a manner as to provide deflection greater than or equal to 15 degrees.

The present disclosure concerns a method and system for imaging a molecular strand (MS). The method comprises providing a sample volume (SV) comprising the strand (MS); providing an excitation beam (EB) having an excitation focus (EF) in the sample volume (SV); scanning the excitation focus (EF) in the sample volume (SV) along a one dimensional scanning line (SL); trapping an end of the strand (MS) in the sample volume (SV) and extending the strand (MS) along a one-dimensional trapping line (LL) parallel to the scanning line (SL); aligning the trapping line (LL) to coincide with the scanning line (SL) to have the scanning excitation focus (EF) coincide with the strand (MS); and recording the fluorescence response (FR) as a function of a plurality of distinct scanning positions (X0) of the excitation focus (EF) along the scanning line (SL).