Abstract: Methods are provided for identifying heterogeneous features, including heterogeneous background regions, in an image of an array, e.g., in an image of a biopolymeric array, such as a nucleic acid array. The subject methods employ an algorithm that employs a different dispersity measure depending on whether the signal features are weaker or stronger. In the subject methods, a toggle parameter, e.g., a single value (i.e., toggle point) or range of values (i.e., toggle range, smooth function), for the array of features is first determined. The toggle parameter is determined using statistics obtained from low signal features on the array. Following determination of the toggle parameter, those features that have a signal intensity that is either: (a) equal to or less than the toggle parameter and have an intra-feature noise metric 1 level, e.g.

Abstract: A method and system for estimating a global background-signal correction for each channel of a feature-based data set, measured by a molecular array scanner, that contributes a feature-intensity data subset to the feature-based data set. The method and system of one embodiment of the present invention selects a set of features for which the measured feature intensities in two or more channels are relatively low and for which the ratio of measured feature intensities follow a central trend in a distribution of feature-intensity ratios for all features within the data set. An ideal feature is computed from the selected set of low-intensity features, from which separate global, residual background-signal corrections for each channel can be calculated and applied to that channel's feature-intensity data subset within the feature-based data set.

Abstract: The invention provides an apparatus and method for determining a signal produced by a micro array device. The apparatus provides an unstructured probe and structured probe. The unstructured probe binds to a target and provides a first signal that can be compared to a second signal produced by a structured probe. A more accurate level of intensity of the first signal can be determined by comparing to the second signal produced by the structured probe. A method for determining a more accurate level of signal intensity produced from the unstructured probes bound to the target is also disclosed.

Abstract: A method and system for extracting data signals from a scanned image resulting from optical, radiometric, or other types of analysis of a molecular array. The positions of corner features are first located. Then, an initial feature coordinate grid is determined from the positions of the corner features. A refined feature coordinate grid is then calculated based on the positions of strong features, and is used to identify the positions of weak features and the positions of the local background regions surrounding all features. Finally, signal intensity values are extracted from the features and their respective local background regions in the scanned image, and background-subtracted signal intensity values, background-subtracted and normalized signal intensity ratios, and variability information and confidence intervals are determined based on the extracted values.

Abstract: A method and system for employing pixel-based, signal-intensity data contained within areas of a scanned image of a molecular array corresponding to features and feature backgrounds in order to determine whether or not the features or feature backgrounds have non-uniform signal intensities and are thus outlier features and outlier feature backgrounds. A calculated, estimated variance for the signal intensities within a feature or feature background is compared to a maximum allowable variance calculated for the feature or feature background based on a signal intensity variance model. When the experimental variance is less than or equal to the maximum allowable variance, the feature or feature background is considered to have acceptable signal-intensity uniformity. Otherwise, the feature or feature background is flagged as an outlier feature or outlier feature background.

Abstract: A method for calibrating different types of signals scanned from a molecular array or calibrating signals scanned from different molecular arrays by employing calibrating probes that generate signals proportional to the total concentrations of labeled target molecules to which the molecular array probes are directed over an entire range of sample solutions, and molecular arrays incorporating sets of calibrating probes.

Abstract: Methods are disclosed for predicting the potential of an oligonucleotide to hybridize to a target nucleotide sequence. A predetermined number of unique oligonucleotides is identified. The unique oligonucleotides are chosen to sample the entire length of a nucleotide sequence that is hybridizable with the target nucleotide sequence. At least one parameter that is independently predictive of the ability of each of the oligonucleotides of the set to hybridize to the target nucleotide sequence is determined and evaluated for each of the above oligonucleotides. A subset of oligonucleotides within the predetermined number of unique oligonucleotides is identified based on the evaluation of the parameter. Oligonucleotides in the subset are identified that are clustered along a region of the nucleotide sequence that is hybridizable to the target nucleotide sequence. The method may be carried out with the aid of a computer.

Abstract: Systems, tools and methods of assaying biological material are used to perform complex sandwich hybridization assays. The tools used comprise biological solution probes that are customized for each assay. The solution probe comprises a first region for hybridizing to a probe, in a generic set of capture probes on a universal assay apparatus, and a second region for hybridizing to a target in a sample. The solution probe assembles the target to the assay apparatus by hybridizing the second region to the target and the first region to the capture probe. In array assays, one or more biological samples, having one or more targets per sample, can be multiplexed on the same universal array comprising the generic set of capture probes in an array pattern of features on the substrate. The customized solution probe addresses and assembles a predetermined target-sample combination onto the array at a corresponding capture probe address location.

Abstract: A method and system for extracting data signals from a scanned image resulting from optical, radiometric, or other types of analysis of a molecular array. The positions of corner features are first located. Then, an initial feature coordinate grid is determined from the positions of the corner features. A refined feature coordinate grid is then calculated based on the positions of strong features, and is used to identify the positions of weak features and the positions of the local background regions surrounding all features. Finally, signal intensity values are extracted from the features and their respective local background regions in the scanned image, and background-subtracted signal intensity values, background-subtracted and normalized signal intensity ratios, and variability information and confidence intervals are determined based on the extracted values.

Abstract: A method, apparatus, and computer program product for reading fluorescence signals from an array of chemical moieties (such as different sequence peptides or polynucleotides, for example different DNA sequences). In the method the spatial sequence of scanned locations need not be the same as the temporal sequence. For example, a later illuminated line may be spatially closer to an earlier illuminated line than is a temporally intervening illuminated line.

Abstract: A method apparatus, and computer program products for generating and using an addressable array of chemical moieties on a substrate. In a processing unit may retrieve array related data from a memory. Such array related data may comprise any of data on a characteristic of the fabricated array, an instruction for reading an array, or an instruction on processing data from a read array. The processing unit may automatically access a program routine for reading the array or processing data from the read array based on the retrieved data.

Abstract: Systems, tools and methods of assaying biological material are used to perform complex sandwich hybridization assays. The tools used comprise biological solution probes that are customized for each assay. The solution probe comprises a first region for hybridizing to a probe, in a generic set of capture probes on a universal assay apparatus, and a second region for hybridizing to a target in a sample. The solution probe assembles the target to the assay apparatus by hybridizing the second region to the target and the first region to the capture probe. In array assays, one or more biological samples, having one or more targets per sample, can be multiplexed on the same universal array comprising the generic set of capture probes in an array pattern of features on the substrate. The customized solution probe addresses and assembles a predetermined target-sample combination onto the array at a corresponding capture probe address location.

Abstract: Nucleic acid arrays that have background features, and methods for using the same, are provided. The subject nucleic acid arrays include both hybridization features and background features, where the background features provide a background signal in a hybridization assay that is made up of a feature substrate component, a nucleic acid probe component and a nucleic acid probe non-specific binding component. In practicing the subject methods, the arrays are contacted with a sample and signals are observed for both hybridization features and background features. The background feature signal is then subtracted from the hybridization feature signal to obtain a background corrected hybridization feature signal that is employed as the output of the assay, e.g., to determine the presence, either qualitatively or quantitatively, of the analyte target nucleic acid in the sample. Also provided are kits for use in practicing the subject methods.

Abstract: Methods for substantially improved detection and analysis in nucleic acid hybridization assays are described. The methods provide the reliable estimation of background signal which derives primarily from nonspecific hybridization. The invention is useful in chemical, biological, medical and diagnostic techniques, as well as for drug discovery.

Abstract: Methods are disclosed for predicting the potential of an oligonucleotide to hybridize to a target nucleotide sequence. A predetermined number of unique oligonucleotides is identified. The unique oligonucleotides are chosen to sample the entire length of a nucleotide sequence that is hybridizable with the target nucleotide sequence. At least one parameter that is independently predictive of the ability of each of the oligonucleotides of the set to hybridize to the target nucleotide sequence is determined and evaluated for each of the above oligonucleotides. A subset of oligonucleotides within the predetermined number of unique oligonucleotides is identified based on the evaluation of the parameter. Oligonucleotides in the subset are identified that are clustered along a region of the nucleotide sequence that is hybridizable to the target nucleotide sequence. The method may be carried out with the aid of a computer.