Abstract:
The invention discloses DNA isolation and purification methods which involve novel washing steps. The disclosed methods provide a means for isolating and purifying DNA from a homogeneous mixture of DNA of other cellular contaminants by treating silica with the homogeneous mixture containing DNA in the presence of a chaotropic salt solution and then washing and separating the washed and treated silica in successive wash steps with aqueous alcohol wash solutions. A first wash step involves washing the treated silica with a first wash solution of at least 95 wt.% alcohol in water. A second wash step similarly involves washing the treated and washed silica with second wash solution of less than 95 wt.% alcohol in water.
Abstract:
An electrophoretic system employing a capillary with at least one end having an electrically conductive coating or layer directly thereon. In order to introduce a plug of sample from a small amount of the sample in a vial, the conductive tip is submersed into the small amount of sample and an electric field is applied at the end by applying the high voltage to the tip in order to electrokinetically inject a plug of the sample. The conductive tip may also be used as a terminal for completing the circuit for applying the high voltage across the capillary column for electrophoresis. The separated components may be collected on a surface or small amount of buffer to reduce sample dilution or mixing of one sample component with a different sample component from the electrophoretic process.
Abstract:
A detection system for sequentially and repetitively scanning a plurality of sample volumes and detecting electromagnetic radiation emitting from each of the sample volumes is described. The system includes a plurality of coplanar side-by-side capillaries each containing a sample volume, an electromagnetic radiation source, a mirror aligned to receive and reflect electromagnetic radiation, a means for moving the mirror, and a detector aligned to receive electromagnetic radiation collected from the sample volumes. In operation, the means for moving the mirror adjusts the mirror position so that the mirror is positioned to receive the electromagnetic radiation from the electromagnetic radiation source and reflect the electromagnetic radiation sequentially and repetitively to the sample volumes. Emitted electromagnetic radiation from the sample volume is collected and directed to a detector where a signal is generated in response to the interaction of the electromagnetic radiation with the sample.
Abstract:
A reagent segment (10) including a body and trough (30) formed therein with the floor of the trough sloped towards a drainage zone (40). The reagent segment is adapted for transporting reagents within an automated analyzer by having at least two protrusions (55A, 55B) on the exterior wall of the trough that fit within corresponding cavities of a transport arm. The reagent segment is retained by a latching mechanism through a protuberance (52) on the exterior surface of the trough that conforms with a hole in the latching mechanism. The reagent segment can further comprise a concave depression (42) on the interior surface of the trough at the drainage zone. The depression (42) can coincide with the protuberance (52) on the exterior surface of the trough that associates with the hole in the latching mechanism. Further, the reagent segment may include at least one indexing rib (62A, 62B), between the exterior surface of the trough and the rim of the body, that can be inserted within an indexing slot of a holding means. Thus, the reagent segment is uniquely adapted for automated handling and processing of reagents in an automated analyzer.
Abstract:
Homogeneous immunoassays and enzyme-substrate assays which use capillary electrophoresis and fluorescent detection systems are described. The method is useful for detecting and/or quantitating the concentration of analytes in a sample.
Abstract:
A method of quantitating proteins in complex samples using capillary electrophoresis can be used both to determine the concentration of a protein in a sample and to determine total protein concentration in the sample. In general, the method of determining the concentration of a marker protein comprises: (1) adding a known quantity of an internal standard compound to a sample containing at least one protein, the internal standard compound selected from the group consisting of benzoic acid substituted with at least one halogen, producing a detector signal in relation to its concentration, and being capable of electrophoretic separation from the protein; (2) subjecting the sample and the internal standard compound to capillary electrophoresis to separate the protein and the internal standard compound from each other and from other components in the sample; (3) measuring the detector signal produced by the internal standard compound and a detector signal produced by the protein to determine a ratio of protein signal to internal standard signal; and (4) determining the concentration of the protein in the sample from a standard curve of protein concentration versus the ratio of protein signal to internal standard signal. A typical protein measurable by the method is albumin. Typically, measurements are made at 214 nm and the internal standard compound is 2,4-dichlorobenzoic acid.
Abstract:
Processes are provided for pretreating body fluid compositions and subsequently analyzing the pretreated body fluid compositions for analytes of interest. Processes for pretreating the compositions include providing size exclusion gel having a molecular weight fractionation range or a molecular weight exclusion such that the size exclusion gel is capable of excluding or fractionating the analytes of interest, and then causing the composition to contact the size exclusion gel in order to separate the analytes from low molecular weight composition components which interfere with the separation and analysis of the analytes of interest. Processes for analyzing pretreated compositions include electrophoretic methods such as capillary zone electrophoresis which involve the separation and detection of analytes of interest.
Abstract:
The present invention is directed to a floating cap or spacer (18) and centrifuge tube assembly (16) which provide adequate resistance to the deforming forces exerted on it. The exterior wall of the tube stem (24) is provided with an annular ridge (34) and the support spacer (18) is provided with an annular groove (36) which mates with the ridge (34) on the tube stem (24) to form an interlocking coupling.
Abstract:
Methods and reagents for the detection and exponential amplification of target nucleic acid molecules are disclosed. The method generally employs a Primer Oligonucleotide which hybridizes in concert with a Blocker Oligonucleotide on a strand of the target molecule, and an End-Run Oligonucleotide which can hybridize to the Blocker Oligonucleotide.
Abstract:
The present invention is directed to a synthesis reaction column which can be conveniently implemented in post synthesis procedures. The reaction column is configured to allow easy connection to a syringe and post synthesis reagent container without requiring connection adapters. In one embodiment, the reaction column (17') configured in the form of a cylindrical column containing the solid-phase support (42) and having a narrow bore tube (18) extending at one end. The tube functions as a piercing tip for accessing a septum sealed vial (60) containing post synthesis reagent. In another embodiment, the reaction column (17'') is configured in the form of a cylindrical barrel (70) enclosing the solid-phase support (74) and having a threaded mount (80) at one end. To complement the reaction column for post synthesis procedures, a vial (92) having a complementary threaded mount (94) at the opening is used for containing a reagent. This vial (92) is conveniently threaded onto the end of the barrel (70) without adapters. Consequently, post synthesis procedures can be implemented conveniently. Both embodiments may be conveniently connected to the reagent delivery system in an automated instrument for carrying out synthesis procedures, as well as post synthesis procedures.