Abstract: A device for separating materials of different densities is provided. A cup body has an internal cavity configured to hold media. An inner wall defines a central body region having an upper and lower end. The upper end is wider than the lower end. An interior shoulder circumscribes the upper end of the central body region. The interior shoulder defines a neck region above the central body region and a shoulder trap below the neck region. The shoulder trap circumscribes the upper end of the central body region and is wider than the neck region. When the device is spun about a central axis, the media travels upward along the inner wall toward the shoulder trap. Relatively more dense material in the media is collected in the shoulder trap, and relatively less dense material is expelled from the device through an opening above the neck region.

Abstract: A device for separating materials of different densities is provided. A cup body has an internal cavity configured to hold media. An inner wall defines a central body region having an upper and lower end. The upper end is wider than the lower end. An interior shoulder circumscribes the upper end of the central body region. The interior shoulder defines a neck region above the central body region and a shoulder trap below the neck region. The shoulder trap circumscribes the upper end of the central body region and is wider than the neck region. When the device is spun about a central axis, the media travels upward along the inner wall toward the shoulder trap. Relatively more dense material in the media is collected in the shoulder trap, and relatively less dense material is expelled from the device through an opening above the neck region.

Abstract: A planar patch-clamp cartridge includes a common ground electrode through a conductive medium reaching into each extracellular chamber. The cartridge is first primed with intracellular solution injected from dispensing tips inserted from above into the intracellular chambers. Then the cartridge is rotated 180 degrees, whereby the intracellular and extracellular chambers assume face-down and face-up positions, respectively. Extracellular solution is then delivered using the same dispensing unit. A plurality of silver tubes engages the intracellular chambers at the end of the rotation to provide electrical conductivity and suction to the intracellular chambers.

Abstract: The cell-delivery unit of a high-throughput electrophysiological testing system is implemented as a reusable movable unit suitable for repetitive delivery of cells to a disposable, multi-aperture patch-clamp tray. An electric field emanating from the patch aperture is used to align the dispenser with the aperture. A set of electrodes in the nozzle of the dispenser is used to detect the electric field and effect the alignment. According to another aspect of the invention, dielectrophoretic fields produced by sets of electrodes in the nozzle form a retaining cage that is used first to suspend a test cell directly above the patch aperture and then to urge the cell toward it. A movable cell sorter may also be coupled to the cell-delivery unit.

Abstract: A polymeric material such as PDMS is molded into an electrode structure containing a micron-size aperture for receiving and forming a giga-ohm seal with a biological membrane. One end of a tube is filled with uncured polymeric material and pressed against a support surface to prevent drainage. A conventional micropipette having a size suitable for sliding through the tube is introduced, tip first, into the tube and is allowed to fall through the polymeric material and rest against the support surface. The assembly is heated to cure the polymer and the micropipette is removed from the tube, thereby leaving a polymeric plug at the end of the tube with an aperture suitable in shape and size for patch-clamp giga-ohm seal electrode applications. A multi-well tray with a polymeric electrode plug in each well is constructed using the same approach.

Abstract: A fluorescent optical imaging system (10) produces two separate spots (S1 and S2) on a sample (12) by a pair of excitation laser beams (B1 and B2) that are generated by first and second lasers (L1 and L2). Excitation laser beams (B1 and B2) pass at slightly different angles, first through an aperture (15) of a 45° fold mirror (13), and then through an objective element (14). As a result, emission light beams (16, 18) are generated from each illuminated spot (S1 and S2) and are reflected and redirected by mirror (13) through a secondary lens (19) before reaching one of two detectors (PMT 1 and PMT 2). Emission beam (16) reflects off a second 45° mirror (22) prior to reaching detector (PMT 1), while emission beam (18) travels directly to (PMT 2). If desired, optical separation elements (24), such as dichroic filters, prisms, or gratings, can be positioned in front of each detector (PMT 1 and PMT 2).

Abstract: A perfusion-chamber structure includes a chamber plate with an extracellular compartment, a partition plate with an electrode aperture, and a foundation plate with an intracellular compartment. A gap between the chamber plate and the partition plate produces a channel for applying suction that draws extracellular solution from the extracellular compartment and facilitates the movement and positioning of a test cell over the electrode aperture. The positioning procedure for the test cell is accompanied by a slight positive pressure applied to the intracellular solution in the intracellular compartment of the perfusion chamber to cause upward fluid flow through the electrode aperture. When the cell is positioned over the electrode aperture, the positive pressure on the intracellular fluid is reversed to suction and the cell is seated thereby to form the seal.

Abstract: A fluorescent optical imaging system (10) produces two separate spots (S1 and S2) on a sample (12) by a pair of excitation laser beams (B1 and B2) that are generated by first and second lasers (L1 and L2). Excitation laser beams (B1 and B2) pass at slightly different angles, first through an aperture (15) of a 45° fold mirror (13), and then through an objective element (14). As a result, emission light beams (16, 18) are generated from each illuminated spot (S1 and S2) and are reflected and redirected by mirror (13) through a secondary lens (19) before reaching one of two detectors (PMT 1 and PMT 2). Emission beam (16) reflects off a second 45° mirror (22) prior to reaching detector (PMT 1), while emission beam (18) travels directly to (PMT 2). If desired, optical separation elements (24), such as dichroic filters, prisms, or gratings, can be positioned in front of each detector (PMT 1 and PMT 2).

Abstract: A fluorescent optical imaging system (10) produces two separate spots (S1 and S2) on a sample (12) by a pair of excitation laser beams (B1 and B2) that are generated by first and second lasers (L1 and L2). Excitation laser beams (B1 and B2) pass at slightly different angles, first through an aperture (15) of a 45° fold mirror (13), and then through an objective element (14). As a result, emission light beams (16, 18) are generated from each illuminated spot (S1 and S2) and are reflected and redirected by mirror (13) through a secondary lens (19) before reaching one of two detectors (PMT 1 and PMT 2). Emission beam (16) reflects off a second 45° mirror (22) prior to reaching detector (PMT 1), while emission beam (18) travels directly to (PMT 2). If desired, optical separation elements (24), such as dichroic filters, prisms, or gratings, can be positioned in front of each detector (PMT 1 and PMT 2).

Abstract: A scanning microscope. An objective lens receives light emitted from a sample in object space and propagates it to image space thereof. A collection lens receives light from the objective lens and propagates it to a focal point in image space of the collection lens. A motor has an axis of rotation that is offset from and extends in substantially the same direction as the optical axis. The motor rotates the objective lens about the axis of rotation to scan across a sample in object space of said objective lens. The sample is mounted on a stage. After each rotation of the objective lens, the stage is advanced in a radial direction with respect to the axis of rotation so that each subsequent scan covers a new part of the sample. For fluorescence microscopy, a laser light source is provided. A wavelength-selective beamsplitter directs the laser light toward the objective lens, while allowing fluorescence or reflected light emitted from the sample to pass through to the collection lens.

Abstract: A polymeric material such as PDMS is molded into an electrode structure containing a micron-size aperture for receiving and forming a giga-ohm seal with a biological membrane One end of a tube is filled with uncured polymeric material and pressed against a support surface to prevent drainage. A conventional micropipette having a size suitable for sliding through the tube is introduced, tip first, into the tube and is allowed to fall through the polymeric material and rest against the support surface. The assembly is heated to cure the polymer and the micropipette is removed from the tube, thereby leaving a polymeric plug at the end of the tube with an aperture suitable in shape and size for patch-clamp giga-ohm seal electrode applications. A multi-well tray with a polymeric electrode plug in each well is constructed using the same approach.

Abstract: A scanning microscope. An objective lens receives light emitted from a sample in object space and propagates it to image space thereof. A collection lens receives light from the objective lens and propagates it to a focal point in image space of the collection lens. A motor has an axis of rotation that is offset from and extends in substantially the same direction as the optical axis. The motor rotates the objective lens about the axis of rotation to scan across a sample in object space of said objective lens. The sample is mounted on a stage. After each rotation of the objective lens, the stage is advanced in a radial direction with respect to the axis of rotation so that each subsequent scan covers a new part of the sample. For fluorescence microscopy, a laser light source is provided. A wavelength-selective beamsplitter directs the laser light toward the objective lens, while allowing fluorescence or reflected light emitted from the sample to pass through to the collection lens.

Abstract: A wavelength-selective mirror selector. A substantially planar wavelength-selective selective mirror holder is disposed askew to a common optical pathway. The holder has a plurality of mirrors mounted thereon and an axle attached normal thereto for rotating the holder so as to place a selected one of the mirrors in the common optical pathway. A motor is connected to the axle for rotating the mirror holder, either selectively or continuously. When a selected mirror is placed in the common optical pathway, the pathway is split so that an excitation light beam of one wavelength traveling along a source optical pathway from a light source is reflected by the mirror along the common optical pathway toward a sample, while light of a different wavelength propagating back along the common optical pathway passes through the mirror to travel along a detector optical pathway to a detector.