Abstract:
The present invention relates to a method of processing forensic trace or touch DNA evidence in order to differentially label cells, and then isolate them into distinct fractions which can be processed using standard downstream DNA profiling methods. A mixture of cells and/or cellular components in fluid suspension are first labeled with one or more markers which bind specifically to genetic sequences of interest, and which can be detected optically. The labeled cells/nuclei are placed into a fluidic cartridge, and are transported via fluid flow to an inspection and separation region, observed and identified according to their labels using optical microscopy, and are moved to output channels corresponding to the different labels, degree of labeling, or combination of labels, and to a different subset of possible genetic profiles. The separated cell fractions are extracted from the cartridge via their respective outputs, and can be genetically profiled via short- tandem-repeat (STR) analysis.
Abstract:
Methods and devices for evaluating a sample, e.g., a plasma sample, from a subject for detecting a target red blood cell protein or antibody are disclosed. Antibody screening methods and devices significantly reduce the level of non-specific binding to a surface (e.g., a test surface bound with a red blood cell (rbcm) preparation), allowing for more efficient detection and reduced test time. The antibody screening method includes an immunoglobulin G (IgG) binding moiety that binds selectively and specifically to the plasma IgG present relative to the binding to the lysed rbcm preparation. An antibody screening method is disclosed whereby non-specific binding caused by lysed red blood cell membrane preparations can be reduced by an agent that specifically cleaves a human IgG in the hinge region. Additional methods and devices for target capturing include a substantially planar surface having an optimized angle for capture, or alternative solid phase geometries for capture.
Abstract:
A rotor is provided for use in a centrifuge system configured to spin the rotor for separating complex fluids. The rotor includes a housing configured to be secured by the centrifuge system and several chambers formed in the housing. Each chamber includes a first chamber portion having a port formed therein and a second chamber portion in fluid communication with the port of the first chamber portion. The second chamber portion may be disposed generally below the port of the first chamber portion. Other rotor designs and methods for separating complex fluids are further disclosed.
Abstract:
A fluidic device includes an arrangement of channels for introducing a sample containing particles of interest into a processing chamber. The chamber is in fluid communication with collecting channels via low-flow connection channels. Particles in the sample may be observed and diverted from the processing chamber by application of a motive force such as optical trapping into a collection channel. Once in the collection channel, particles can be collected, including by trapping in a porous matrix.
Abstract:
A fluidic device includes an arrangement of channels for introducing a sample containing particles of interest into a processing chamber. The chamber is in fluid communication with collecting channels via low-flow connection channels. Particles in the sample may be observed and diverted from the processing chamber by application of a motive force such as optical trapping into a collection channel. Once in the collection channel, particles can be collected, including by trapping in a porous matrix.
Abstract:
Methods and devices for evaluating a sample, e.g., a plasma sample, from a subject, for detecting a target red blood cell protein or antibody are disclosed. In one embodiment, optimized antibody screening methods and devices significantly reduce the level of non-specific binding to a surface (e.g., a test surface bound with a red blood cell (rbcm) preparation), thus allowing for more efficient detection and reduced test time. In one embodiment, the optimized antibody screening method includes an immunoglobulin G (IgG) binding moiety that binds selectively and specifically to the plasma IgG present relative to the binding to the lysed rbcm preparation. In another embodiment, an optimized antibody screening method is disclosed whereby non-specific binding caused by lysed red blood cell membrane preparations can be reduced by an agent that specifically cleaves a human IgG in the hinge region. In other embodiments, the invention provides methods and devices for target capturing that include a substantially planar surface, optionally having an optimized angle, for capture. Alternative solid phase geometries for capture are disclosed. Optimized methods for cell deposition are also disclosed. Thus, optimized methods, devices, kits, assays for evaluating a sample are disclosed.
Abstract:
The present invention relates to methods and apparatuses for the detection of positional freedom of particles used in biological, biochemical, physical, biophysical, and chemical analyses. In particular, the present invention relates to methods and apparatuses which can detect and characterize a population of particles/cells based upon their detected mobility. In one embodiment consistent with the invention, detection of certain cells is based on differences detected in populations of cells that bind to a substrate and those that exhibit weaker binding forces. Initially, cells are settled on the substrate, and in the presence of gravitational, natural thermodynamic pressure fluctuations, and other random or applied forces, some of the particles may exhibit translational movement. Particle movement is detected, and measurements are computed, according to the methods and apparatuses of the present invention, to determine the binding of specific analytes.
Abstract:
A fluidic device includes an arrangement of channels for introducing a sample containing particles of interest into a processing chamber. The chamber is in fluid communication with collecting channels via low-flow connection channels. Particles in the sample may be observed and diverted from the processing chamber by application of a motive force such as optical trapping into a collection channel. Once in the collection channel, particles can be collected, including by trapping in a porous matrix.
Abstract:
Methods and apparatus for analyzing surface properties of particles are provided. A method for analyzing the surface properties of the particle includes a associating a first particle with a first capture zone having a specific binding affinity for a first chemical species, applying an optical force to the first particle, sensing a response of the first particle to the optical force, and using the sensed response to determine the presence, absence or quantity of the first chemical species on the first particle surface. This process may be repeated in parallel to test multiple particles. In addition to directly testing the surface properties of the particles, the method can be used in direct, indirect and competitive assays to determine the presence, absence or quantity of free or immobilized analytes. A fluidic cartridge with capture zones having avidities that are tuned for the use of optical forces is provided. A software routine for performing the method is also provided.
Abstract:
The present invention relates to methods and apparatuses for the detection of positional freedom of particles used in biological, biochemical, physical, biophysical, and chemical analyses. In particular, the present invention relates to methods and apparatuses which can detect and characterize a population of particles/cells based upon their detected mobility. In one embodiment consistent with the invention, detection of certain cells is based on differences detected in populations of cells that bind to a substrate and those that exhibit weaker binding forces. Initially, cells are settled on the substrate, and in the presence of gravitational, natural thermodynamic pressure fluctuations, and other random or applied forces, some of the particles may exhibit translational movement. Particle movement is detected, and measurements are computed, according to the methods and apparatuses of the present invention, to determine the binding of specific analytes.