|Date: November 24, 1997||Chart|
The measurement of chemiluminescence (light emitted from a chemical reaction) and bioluminescence (naturally occurring luminescence that is often enzyme-catalyzed) is made possible by the use of luminometers. The majority of these devices utilize photomultiplier tubes that detect light emitted from the reaction, with the light reaching the tube being proportional to the concentration of the limiting reagent in the reaction. Luminometry provides a higher signal-to-noise ratio than fluorometry. Common applications of luminometry include reporter gene assays-used to study gene expression and regulation-and ATP determinations.
The Lumi-ScintTM from Bioscan is a small, benchtop luminometer optimized for counting luminescence and liquid scintillation counting (LSC). Using photomultiplier tube detection, the Lumi-Scint reads one tube or LSC vial at a time. Applications include quantitative polymerase chain reaction (PCR) and reporter gene assays. Bioscan also offers the Lumi-One Luminometer, which has the same features as the Lumi-Scint except LSC capabilities.
MGM Instruments provides the compact OPTOCOMPTM-P Portable Luminometer, which features 8-hour battery operation and a standard printer for paper documentation. The user is guided by the unit's menu-driven software, and data reduction is limited to raw counts to provide cost-effective luminescence assays.
The Lumi-Tec from St. John Associates is available in three configurations: a test tube model for discrete samples, a flow cell model, and a flow cell model with an integral mixing tee for the addition of a reagent. The test tube instrument uses glass or polystyrene cuvettes, while the flow cell models have a 70 ml flow cell. (Other cell volumes are available on request.) Data are displayed on an LED readout.
Packard TopCount® NXT
Analytical Luminescence Laboratory Monolioght® 3010
Cardinal Associates FluteTM 400
EG&G Wallac LB9507
Distributed in the United States by EG&G Wallac, the AutoLumat LB 953 is optimized for bioluminescence, cellular chemiluminescence, and immunoassays. The LB 953 can process a sample chain of up to 180 sample carriers, using up to three injectors simultaneously. The LB 953 also features user- interchangeable filters, optional temperature control of the sample compartment (from 5°C above ambient to 45°C), and a wide selection of software programs for various applications.
The Lumat LB 9507, also from EG&G Wallac, features a motor- driven rotating chamber for two tubes-one for measuring and one for loading and unloading-allowing tubes to be loaded and unloaded during sample measurements. Up to two programmable, automatic, variable volume injectors can be used on the LB 9507. Measured raw data are simultaneously sent to a serial port, which allows data acquisition from an external computer, the software of which is dual luciferase assay compatible.
MGM Instruments OPTOCOMP I
To eliminate static discharge interference with luminescence readings, BBI-Source Scientific integrated an innovative static-suppress feature in its E/LUMINATM II Luminescence Analyzer. The software of this unit is designed for assay versatility, allowing simple set-up menus for injection timing and kinetic read modes. An extensive menu of data reduction, standard curve fits, concentration units, and results flags is available for custom defining user protocols. The tracking program of the E/LUMINA II monitors reagent usage and provides reports during operation.
The TD-20/20 from Turner Designs can be outfitted with programmable single or dual internal auto injectors and is capable of reading a 35 mm culture dish, a 28 mm scintillation vial, test tubes, and microfuge tubes. The TD-20/20 includes software for Promega's Dual-LuciferaseTM Reporter Assay System and has a kinetics feature for reactions with unstable light output. An optional printer is also available.
EG&G Wallac MicroLumatPlus LB 96V
The new MLXTM Luminometer from DYNEX Technologies is designed for glow endpoint, glow kinetic, or flash reactions and is controlled by DYNEX's WindowsTM-based software system RevelationTM. As a component of Revelation, Assay WizardTM utilizes a step-by-step tab dialogue approach to programming all operating and data reduction aspects of an assay. The MLX accommodates up to three positive displacement syringe dispensers. Revelation has a new software application that accomodates the Promega Dual LuciferaseTM Reporter Assay
rosys anthos Lucy I
The anthos lucy 1 from rosys anthos is a microplate luminometer and photometer. Up to two precision dispensers are software controlled for delivery from 10 ml to well capacity in increments of 1 ml. Also, the plate transport provides a shaking function for mixing. The measurement chamber is Peltier controlled, allowing temperatures to be adjusted from 4°C below ambient to 40°C in steps of 1°C. L1Com under WindowsTM or MacL1Com for MacintoshTM-based systems enables remote operation of lucy 1 including test execution, result upload, test upload, and test download.
SFRI's lumax 3 is a 96-well microplate luminometer equipped with two to four injectors, allowing both flash and glow assays to be performed. The lumax 3 is self-calibrating, and results can be obtained in as little as 40 seconds. The unit has a very small footprint, is lightweight, and has an incubation range that extends to 55°C.
The lumax 2 from SFRI is about half the size of the lumax 3 and can read glow assays. SFRI also provides the Alpha 4LS, which the company claims is the only completely automated microtiter plate system that reads both optical density and luminescence simultaneously. The system accepts up to 384-well plates and is only 41 inches wide.
The TR717TM Microplate Luminometer from Tropix reads 96- or 384-well plates and measures all types of chemi- and bioluminescence (flash and glow kinetics). Up to two programmable reagent injectors expand assay design capabilities. The TR717 is controlled via an internal keyboard, but its intuitive and easy-to-use Windowsª software can greatly increase data analysis and handling capabilities. Tropix also provides 12 customized kits and numerous reagents for luminescence assays. An optional robotics package allows for the integration of the TR717 into most robotic systems. Tropix also provides 12 customized kits and numerous chemiluminescent reagents.
Pharmacia Biotech DyNA Quant 200
Turner Designs TD-360
The DyNA QuantTM 200 from Pharmacia Biotech is designed specifically for the accurate quantitation of small-volume samples with low DNA concentrations using the Hoechst 33258 dye. This dye binds preferentially to double-stranded DNA, thus allowing accurate quantitation even in the presence of RNA, proteins, and/or nucleotides in cell lysates. The DyNA Quant 200 can accept one standard cuvette or capillary cuvette.
St. John Associates provides the FLUORO-TEC Fluorometer as a test tube model or a flow cell system. Cuvette adapters are available for capillary tubes, round tubes, and a rectangular spectrofluorometer cell. The FLUORO-TEC is only 41/2 inches wide and weighs only 8 pounds. This machine is suited for a wide range of fluorescence-based methods.
The 10-AU-005-CE Field Fluorometer from Turner Designs is a rugged, field-portable instrument that is capable of continuous-flow or discrete sample analyses. The unit is equipped with removable filter paddle, and the O-rings of the filter paddles are compression-sealed, ensuring a watertight design. With internal data logging, up to 64,800 data points can be stored in the instrument's memory and saved, even when the instrument is not continuously powered. Data can be downloaded, stored in ASCII format, and imported into a spreadsheet format for manipulation.
Also available from Turner Designs is the TD-700 Laboratory Fluorometer, designed as a compact, low-cost benchtop fluorometer. Automatic range optimization allows the automatic setting of range, gain, and resolution, eliminating operator error due to working in the wrong range. A multiassay filter cylinder houses eight interchangeable filters for four separate applications. The TD-700 accommodates test tubes, square cuvettes, and optional 100 ml minicell or 9 ml microcell adapters. The Kinetics software outputs data to a computer or printer at selectable intervals.
Brand new from Turner Designs is the TD-360 Mini-Fluorometer, a dedicated, single-cuvette flurometer that features a unique quick-change filter holder, easily-accessible lamp module, RS232 serial interface, and ability to store up to five calibration settings. A variety of compounds can be measured in standard square cuvettes or 100 ml disposable minicells using application-specific optical filters and lamp sources. Sensitivities as low as 500 picograms/ml DNA using PicoGreen are easily achievable.
Bio-Tek offers the FL600 Fluorescence and Absorbance Microplate Reader. The FL600 can scan 6- to 384-well microplates (including Terasaki plates) and its dual optical channels provide for software selection of top or bottom epifluorescence measurement. Four probe sizes, high resolution probe movement and a large optical chamber enable reading of practically any container, including PCR tubes. Six position and independently controlled filter wheels provide many filter combinations for a variety of probes and dyes. Temperature control up to 50°C supports kinetic capabilities. The new KC4TM for WindowsTM data reduction program features extensive graphics and data reduction capabilities and is simple enough for beginning users to operate.
The FLUOstar from BMG LabTechnologies can measure a variety of plate formats. By defining the locations of the corner wells, along with the number of rows and columns, the FLUOstar can measure any plate format, including 384-well plates and Terasaki plates. The FLUOstar's software- selectable flash control allows both standard and time- resolved fluorescence applications. PC software provides instrument flexibility, and available templates include replicates, standard curve regression, graphics, and unknown sample calculations.
Bio-Tek Instruments FL600
BMG Lab Technologies FLUOstar
Instruments S.A. also offers the Fluorolog3-Tau3 Lifetime accessory, which allows picosecond to microsecond fluorescence lifetime measurement capability in the frequency domain. This accessory is ideal for research in energy transfer and dynamic depolarization. Another powerful research tool from Instruments S.A. is the Fluoromax-2. The Fluoromax-2 is a self-contained, benchtop spectrofluorometer with high speed and sensitivity, ideal for a wide range of analytical fluorescence measurements.
Instruments S.A. Fluorolog-3
The HTS 7000TM Bio Assay Reader from Perkin-Elmer was designed specifically for rapid turnaround of nonradioactive, photometric analyses on large arrays of small volume samples. The WindowsTM-based HTSoftTM instrument control and data analysis software provides simple software options which allow selection of stored user methods for top and bottom reading fluorescence or through-well absorbance measurements down to 260 nm. No hardware reconfiguration is necessary to change measurement modes and all plate types and styles from 6 to 384 wells can be added to the user library. From DNA and protein quantitation, cell function assays, kinetics, and ELISA assays, the versatility of providing three instruments in one platform allows the user to perform virtually any fluorescence- or absorbance-based biochemical assay on the HTS 7000.
Molecular Dynamics BioLumin 960
Tecan US SPECTRAFluor
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