Abstract: Methods and systems for determining kinetic parameters are provided. The methods and systems may use a surface having a matrix attached thereto and probe molecules bound to the matrix. Target molecules may be introduced and bind reversibly to the probe molecules. As target molecules are introduced, a first amount of intermolecular complex is generated between the target molecules and the probe molecules and monitored. Once a threshold first amount intermolecular complex is exceeded, introduction of the target molecules may cease. At this point, competitive inhibitor molecules may be introduced and bind to free target molecules produced from continued dissociation of the intermolecular target-probe complex. An amount of the first intermolecular complex may be monitored. This amount may be indicative of the kinetics of a second intermolecular complex between the free target molecules and the competitive inhibitor molecules.

Abstract: Provided herein are anti-KRas antibodies that bind to mutant KRas-GDP and alkylated mutant KRas-GDP and methods of using the same. Also provide herein are method of screening for KRas inhibitors and methods of measuring binding of KRas to the antibodies described herein.

Abstract: A referencing method for an optical biosensor system using a single sensing region is provided. The method involves limiting the ligand immobilized in a single sensing region to only a portion thereof. In one embodiment, this is accomplished by selectively deactivating a portion of the sensing surface to prevent immobilization of ligand to that portion. As a result, a reference response can be recorded in the same sensing region as a molecular interaction response. Thus, the bulk refractive index can be accurately accounted for in measuring the kinetics of a molecular interaction.

Abstract: A referencing method for an optical biosensor system using a single sensing region is provided. The method involves limiting the ligand immobilized in a single sensing region to only a portion thereof. In one embodiment, this is accomplished by selectively deactivating a portion of the sensing surface to prevent immobilization of ligand to that portion. As a result, a reference response can be recorded in the same sensing region as a molecular interaction response. Thus, the bulk refractive index can be accurately accounted for in measuring the kinetics of a molecular interaction.

Abstract: Dispersion injection methods for determining biomolecular interaction parameters in label-free biosensing systems are provided. The methods generally relate to the use of a single analyte injection that generates a smoothly-varying concentration gradient via dispersion en route to a sensing region possessing an immobilized binding partner. The present method incorporates the use of an internal standard which provides a reference as to the dispersion conditions present which can then be used to calculate an effective diffusion coefficient for the analyte of interest based on a universal calibration function. The effective diffusion coefficient can then be incorporated into the appropriate dispersion model to provide a calibrated dispersion model. The calibrated dispersion model can then be incorporated into the desired interaction model to provide a reliable representation of the analyte concentration at the sensing region at any time during the injection.

Abstract: A referencing method for an optical biosensor system using a single sensing region is provided. The method involves limiting the ligand immobilized in a single sensing region to only a portion thereof. In one embodiment, this is accomplished by selectively deactivating a portion of the sensing surface to prevent immobilization of ligand to that portion. As a result, a reference response can be recorded in the same sensing region as a molecular interaction response. Thus, the bulk refractive index can be accurately accounted for in measuring the kinetics of a molecular interaction.

Abstract: A referencing method for an optical biosensor system using a single sensing region is provided. The method involves limiting the ligand immobilized in a single sensing region to only a portion thereof. In one embodiment, this is accomplished by selectively deactivating a portion of the sensing surface to prevent immobilization of ligand to that portion. As a result, a reference response can be recorded in the same sensing region as a molecular interaction response. Thus, the bulk refractive index can be accurately accounted for in measuring the kinetics of a molecular interaction.

Abstract: The present invention relates to a method for testing multiple analyte concentrations within a biosensor system through a single injection of sample. The method involves flowing a fluid sample containing a neat analyte concentration along a flow path in a fluid system and diluting the sample by causing it to merge with a fluid that is free of analyte in a second flow path under laminar flow conditions. The merged fluid stream is directed through a turbulent third flow path of a very low dead volume. The third flow path carries the merged fluid stream to a sensing region where the analyte is exposed to an immobilized ligand. The concentration of analyte can be controlled in this method by adjusting the flow rates of the sample flow and analyte-free fluid flow. A fluidic system for carrying out this method is also disclosed.

Abstract: A single injection gradient with a biosensor, both structural and methodological, achieves the binding of analyte to immobilized ligand over a wide concentration range without the necessity of regeneration of the sensing area. A gradient of concentrations adjacent to or within a flow cell facilitates kinetic analysis of interactions without requiring multiple discrete volumes or injections to achieve a range of concentrations. A continuous gradient fluid is preferably formed directly adjacent to the flow cell inlet or a region of sample/buffer dispersion at an injection point into a flow channel of a flow cell. The analyte gradient may be flowed through the flow cell from a low analyte concentration. Multiple component gradients are also provided.

Abstract: I Injection methods for determining biomolecular interaction parameters such in label-free biosensing systems are provided. The methods generally relate to analyte sample injection methods that generate well-defined analyte concentration gradients en route to a sensing region possessing an immobilized binding partner. The injections conditions are generally established according to a set of rules that create a dispersion event that can be accurately modeled by a dispersion term. The dispersion term is incorporated into the desired interaction model to provide a reliable representation of the analyte concentration gradient profile, The resulting interaction model is then fitted to a measured binding response curve in order to calculate the interaction parameters.

Abstract: The present invention relates to a method for testing multiple analyte concentrations within a biosensor system through a single injection of sample. The method involves flowing a fluid sample containing a neat analyte concentration along a flow path in a fluid system and diluting the sample by causing it to merge with a fluid that is free of analyte in a second flow path under laminar flow conditions. The merged fluid stream is directed through a turbulent third flow path of a very low dead volume. The third flow path carries the merged fluid stream to a sensing region where the analyte is exposed to an immobilized ligand. The concentration of analyte can be controlled in this method by adjusting the flow rates of the sample flow and analyte-free fluid flow. A fluidic system for carrying out this method is also disclosed.

Abstract: A fluidic configuration, both structural and methodological, for the injection of sample greatly reduces dead volume allowing rapid transition to 100% sample in a flow cell. For a continuous flow injection analysis system the structure and method provide counter flows to remove in one direction the dispersed region of the sample to waste before injecting non-dispersed sample into the flow cell by reversing the effective flow direction. The injection point itself is directly adjacent to the flow cell where all channels are microfluidic channels. Therefore, only the flow cell volume needs to be displaced during injection of sample in order to achieve 100% transition to sample within the flow cell. This greatly accelerates the rise and fall times thereby extending the kinetic range of the real-time interaction analysis instrument. In addition such rapid transition to sample improves overall data quality thereby improving kinetic model fitting.

Abstract: A single injection gradient with a biosensor, both structural and methodological, achieves the binding of analyte to immobilized ligand over a wide concentration range without the necessity of regeneration of the sensing area. A gradient of concentrations adjacent to or within a flow cell facilitates kinetic analysis of interactions without requiring multiple discrete volumes or injections to achieve a range of concentrations. A continuous gradient fluid is preferably formed directly adjacent to the flow cell inlet or a region of sample/buffer dispersion at an injection point into a flow channel of a flow cell. The analyte gradient may be flowed through the flow cell from a low analyte concentration. Multiple component gradients are also provided.

Abstract: A skin assembly is disclosed. The skin assembly includes a skin formed from a material that is capable of being stitched, a thread passing through the skin to form a stitch pattern on a first surface of the skin and a loop extending from a second surface of the skin opposite the first surface, and a substrate coupled to the loop of the thread to secure the thread in the skin.

Abstract: A fluidic configuration, both structural and methodological, for the injection of sample greatly reduces dead volume allowing rapid transition to 100% sample in a flow cell. For a continuous flow injection analysis system the structure and method provide counter flows to remove in one direction the dispersed region of the sample to waste before injecting non-dispersed sample into the flow cell by reversing the effective flow direction. The injection point itself is directly adjacent to the flow cell where all channels are microfluidic channels. Therefore, only the flow cell volume needs to be displaced during injection of sample in order to achieve 100% transition to sample within the flow cell. This greatly accelerates the rise and fall times thereby extending the kinetic range of the real-time interaction analysis instrument. In addition such rapid transition to sample improves overall data quality thereby improving kinetic model fitting.