Abstract:
Un système de commande de la température est utilisé pour commander de manière précise la température d'un courant fluide dans un système analytique conçu pour l'analyse des constituants chimiques du courant fluide. Un exemple d'utilisation en chromatographie est la colonne chromatographique dans un système d'analyse des acides aminés. Le système de commande de température utilise un ensemble de modules thermoélectriques pour transférer la chaleur entre un bloc thermoconducteur qui tient la colonne chromatographique et un puits thermique à échange d'air qui obtient la chaleur du milieu ambiant ou rejette la chaleur dans le milieu ambiant, en fonction des besoins. Le système de commande effectue la régulation de la température à une vitesse très élevée de manière à réduire au minimum le temps de recyclage de l'instrument.
Abstract:
An automatic chemistry analyzer is provided having a high throughput and a high reliability. The analyzer uses nephelometric and turbimetric analyzers (68) to analyze a wide variety of parameters within liquid samples typically generated in, for example, a large medical testing laboratory. The machine employs a unique probe (84) and stirring rod (86) assembly (80) mounted at a slight angle ( alpha ) with one another using rack and pinion assemblies (106) so that the lower end of the probe (84) and the lower end of the stirring rod (86) are in very close proximity to one another. This feature allows the machine to be used in unusually small reaction cuvettes (54). The analysis machine also includes an onboard control sample (78) so that the machine can be programmed to periodically calibrate its analyzing equipment during the course of normal operation. The machine also includes a sample station carousel (24) having retainer clips (39) for retaining a sample container rack (30) which is constructed to retain a bar-coded card (37) containing information regarding reagents used in the machine. A bar code reader (47) located proximate to the sample carousel reads the bar-coded reagent information into the controller. Also provided are a cuvette wash station (130) and a waste trap assembly (138).
Abstract:
The invention provides a vacuum manifold which can be conveniently used in semi-automated and fully-automated laboratory machines to carry out a sequence of vacuum-assisted laboratory manipulations on a large number of individual liquid samples. The invention has a base (12) which is sized and dimensioned to accept and retain a first liquid receptacle (24), such as a microtitre dish. Generally, the base (12) has a bottom wall (16) and side walls (18) and the first receptacle (24) is designed to be retained within the side walls (18). The invention also has an adapter frame which is sized and dimensioned to accept and retain a second liquid receptacle (30), such as a second microtitre dish. The adapter frame (14) is typically a rectangular frame structure having a lip (32) which supports the second receptacle (30). The base (12) generally has a port (26) which is attachable to a source of vacuum. In operation, the first liquid receptacle (24) is placed within the base (12), the adapter frame (14) is placed on top of the base (12) and the second liquid receptacle (30) is placed on the adapter frame (14) so that a second receptacle (30) is located directly above the first receptacle (24). When vacuum is applied to the base using the vacuum port (26), a uniform vacuum is drawn along the bottom of the second liquid receptacle (30) which provides a driving force which acts upon liquid within the second receptacle (30). In a typical operation, the bottom of the second receptacle (30) is a filtration membrane and the vacuum is used to draw liquid from the second receptacle (30) across the filtered membrane into the first receptacle (24). Because of its modular construction, the various elements of the vacuum frame are easily stacked in stacking frames disposed to one side of the vacuum manifold. This stacking capability allows a large number of vacuum-assisted laboratory operations to be carried out on multiple sets of liquid samples without the necessity of a large amount of horizontal lab bench area. The stacking capability also facilitates the adaption of the invention with robotic equipment to provide a fully-automated laboratory processing tool.
Abstract:
A serum index sample probe having a cuvette (17) with a cylindrical channel (39) coupled between a hollow cylindrical member (25) and a hollow cylindrical needle (23) by an optics block (13). The channel and the needle have matching diameters and are coaxially aligned along an axis (41), defining a smooth bore therebetween to reduce dead volumes. The cuvette is positioned proximate to a puncturing tip of the needle which, along with the smooth bore, reduces turbulence and bubbles in the flow path. The optics block (13) provides a plurality of optical paths to the cuvette while maintaining a linear flow path. The optics block is a manifold having a central aperture (15), a perimeter surface (61) disposed concentrically about the central aperture, and a plurality of bore holes (55, 57, 59).
Abstract:
Activated nucleoside derivatives formed in situ of general formula (I) in which one of R and R is R and the other is -P(R2)OR , wherein R is a substituted arylcarbonyl group, R is R O or R , R is a hydroxyl-protecting group and B is a purine or pyrimidine base. Particularly preferred are those compounds wherein R is 2,4-dinitrophenylcarbonyl. The compounds of general formula (I) are prepared using the corresponding carboxylic acids; these acids are generally more soluble in acetonitrile (for example, to the extent of 1.5 M for 2,4-dinitrobenzoic acid) and work as activators at lower concentrations. The compounds of general formula (I) may be employed in conventional coupling reactions (for example, solid phase synthesis) to prepare oligonucleotides which are indistinguishable from those prepared using the heretofore-known tetrazole-activated nucleoside intermediates.
Abstract:
A method and system of identifying a rotor of a centrifuge employ an approach that uses two tiers of model selection. Firstly, the moment of inertia of a rotor is calculated for a first measured acceleration. The indication of moment of inertia is utilized to disqualify a number of rotor models and to select a subset of models. In a second tier, windage power of the rotor is calculated in a manner that isolates windage from inertial drag. In one embodiment, drive torque is measured with the rotor operated at a high constant speed. Alternatively, windage is calculated using data obtained during a second measured acceleration. The accuracy of the computation is enhanced by taking into account the moment of inertia as one form of resistance to the second acceleration. Based upon the indication of windage power, at least one rotor model within the subset is disqualified. Upon identification of the rotor, the centrifugal process can be maintained at a maximum safe speed. Moreover, a refrigeration offset circuit is controlled to provide a dynamic temperature correction with changes in windage power.
Abstract:
A method for detecting an analyte in a sample uses both the specificity of an enzymatic reaction and the separation power of capillary electrophoresis. In general, the method comprises: (1) subjecting a first aliquot of the sample to an analytical technique such as capillary electrophoresis, which generates a first output such as an electropherogram; (2) reacting a second aliquot of the sample in an enzyme-catalyzed reaction converting the analyte into a product, the product being detectable by the analytical technique; (3) subjecting the second aliquot to the analytical technique to generate a second output; (4) in the case of electrophoresis, measuring the absorbance of the first and second outputs (electropherograms) as a function of migration distance along the electropherogram at at least one wavelength at which either the analyte or the product absorbs to produce a first absorbance scan and a second absorbance scan; and (5) comparing the first absorbance scan with the second absorbance scan to detect the analyte. The reaction can involve a coenzyme and the analytical technqiue can be directed to the coenzyme. Alternatively, at least two enzymes can be used, the first enzyme generating a first product that is then acted upon by the second enzyme.
Abstract:
Disclosed herein are surface activated, organic polymers useful for biopolymer synthesis. Most preferably, aminated biaxially oriented polypropylene is used for the synthesis of oligonucleotides thereto, and these devices are most preferably utilized for genetic analysis of patient samples.