Abstract:
A microfabricated device, manifold system and method for electrokinetically moving biological and chemical samples including a multiplexed detection chamber for receiving a plurality of adjacent sample streams to be detected. The device includes a plurality of adjacent input channels connected to the detection chamber via an enlarged section having an expanding taper at its widest end or other shapes so that adjacent sample streams enter the detection chamber and remain discrete for a threshold distance to the detection chamber to minimize lateral diffusion.
Abstract:
Methods, compositions and kits are disclosed for determining one or more target polypeptides in a sample where the target polypeptides have undergone a post-translational modification. A mixture comprising the sample and a first reagent comprising a cleavage-inducing moiety and a first binding agent for a binding site on a target polypeptide is subjected to conditions under which binding of respective binding moieties occurs. The binding site is the result of post-translational modification activity involving the target polypeptide. The method may be employed to determine the target polypeptide itself. In another embodiment the presence and/or amount of the target polypeptide is related to the presence and/or amount and/or activity of an agent such as an enzyme involved in the post-translational modification of the target polypeptide. The interaction between the first binding agent and the binding site brings the cleavage-inducing moiety into close proximity to a cleavable moiety, which is associated with the polypeptide and is susceptible to cleavage only when in proximity to the cleavage-inducing moiety. In this way, an electrophoretic tag for each of the polypeptides may be released. Released electrophoretic tags are separated and the presence and/or amount of the target polypeptides are determined based on the corresponding electrophoretic tags.
Abstract:
Methods, compositions and kits are disclosed for determining one or more target polypeptides in a sample where the target polypeptides have undergone phosphorylation. A mixture comprising the sample and a first reagent comprising a cleavage-inducing moiety and an IMAC resin for a binding site on a target polypeptide is subjected to conditions under which binding of respective binding moieties occurs. The binding site is the result of phosphorylation activity involving the target polypeptide. The method may be employed to determine the target polypeptide itself. In another embodiment the presence and/or amount of the target polypeptide is related to the presence and/or amount and/or activity of an agent such as an enzyme involved in phosphorylation of the target polypeptide. The interaction between the IMAC resin and the binding site brings the cleavage-inducing moiety into close proximity to a cleavable moiety, which is associated with the polypeptide and is susceptible to cleavage only when in proximity to the cleavage-inducing moiety. In this way, an electrophoretic tag for each of the polypeptides may be released. Released electrophoretic tags are separated and the presence and/or amount of the target polypeptides are determined based on the corresponding electrophoretic tags.
Abstract:
Cytochrome P-450 assay methods and kits for the methods are provided employing a cytochrome P-450 enzyme, substrates characterized by having an oxidizable methylene group oxidized to an aldehyde and a fluorescent hydrazine. A fluorescent hydrazine is added to the reaction mixture and the resulting hydrazone analyzed by capillary electrophoresis. The method finds use in evaluating compounds for enzyme modulating activity.
Abstract:
Devices and methods are provided using microfluidic devices for manipulating small volumes and determining a variety of chemical and physical events. The devices rely upon an opening to the atmosphere of a small volume in a zone, where a sample is placed in the zone where evaporation can occur. The zone is maintained in contact with a liquid medium that serves to replenish the liquid in the zone and maintain the composition of the mixture in the zone substantially constant. The diffusion of components in the zone is restricted during the course of the determination by the liquid flux into the zone.
Abstract:
Multiplexed determinations of large numbers of events are achieved in an accurate and simple manner by using a combination of different oligonucleotides, which serve for both capture and release from a support and strand displacement oligonucleotides for sequential release of groups of oligonucleotides. Also included, as part of the oligonucleotide reagents may be identifiers, which serve to identify a particular characteristic. The method is illustrated using primers for initiation of chain extension joined to or serving as the capture/release sequence, where the extended primer has an identifier. After extending the primer, the extended primers are captured and independently released and the released extended primers assayed. The subject method finds application for nucleic acid sequence determinations, single nucleotide polymorphism determinations, identification of nucleic acid fragments, and the like.
Abstract:
Integrated electrophoretic microdevices comprising at least an enrichment channel and a main electrophoretic flowpath are provided. In the subject integrated devices, the enrichment channel and the main electrophoretic flowpath are positioned so that waste fluid flows away from said main electrophoretic flowpath through a discharge outlet. The subject devices find use in a variety of electrophoretic applications, including clinical assays.
Abstract:
Procedimiento para la unión libre de sustancias ajenas de dos piezas (2, 3; 5, 6) mutuamente adyacentes de material plástico, al mismo tiempo, que cada pieza posee una superficie de contacto prevista a través de la que se unen las piezas y que al menos una pieza posee en la superficie de contacto cavidades con microestructura y/o nanoestructura, caracterizado porque - la superficie (K) de contacto prevista de al menos una de las dos piezas (2, 3, respectivamente 5, 6), con la que esta limita con la otra pieza (3, 6, respectivamente 2, 5) en la unión se expone, al menos por zonas, a una radiación rica en energía, de manera, que se reduzca la temperatura de transición vítrea en una capa (R, R'') del borde, - las dos piezas (2, 3; 5, 6)son llevadas a su posición funcional mutua y - a continuación se calienta, para el establecimiento de la unión de las piezas (2, 3; 5, 6) al menos la capa (R, R'') del borde modificada con el proceso de irradiación al menos en la zona de su superficie hasta una temperatura, que se halle por encima de la temperatura de transición vítrea de la capa (R, R'') del borde modificada con la irradiación, pero por debajo de la temperatura de transición vítrea de las zonas no modificadas de la pieza (2, 3; 5, 6) correspondiente, de manera, que las cavidades con microestructuras y/o nanoestructuras conserven su estabilidad de formas.
Abstract:
Capillary electrophoresis is performed under conventional conditions in microchannels having a norbornene based polymer surface. The norbornene based polymers can be used as a solid substrate for forming the necessary features for a microfluidic device, where the entire device may be made of norbornene based polymer. Conveniently, a norbornene based polymer layer having a lower glass transition temperature may be used to adhere a cover or enclosing layer to the substrate to enclose the microchannels and provide a bottom for the reservoirs.