Reagents for PCR
Applied Biosystems kicks things off with the release of its new range of reagents designed for streamlining quantitative reverse transcription polymerase chain reaction (RT-PCR) in RNA-based research applications.
The reagents are specifically meant for one or two-step reverse transcription to quantitative PCR reactions. Both techniques have become increasingly popular in the analysis of gene expression.
One method involves including the RT step into the same tube as the PCR reaction (one-step). The other method involves creating cDNA first by means of a separate reverse transcription reaction and then adding the cDNA to the PCR reaction (two-step).
There are advantages and disadvantages to both systems. The advantages to one-step real-time RT-PCR is that it is quicker to set up, less expensive to use, and involves less handling of samples, thereby reducing pipetting errors, contamination, and other sources of error.
The main advantage to two-step RT-PCR is that typically random hexamer or oligo dT primers are used in an RT reaction in a separate tube. This allows for the ability to convert all the messages in an RNA sample into cDNA, which would allow for archiving of samples and future testing of other genes.
Applied Bio's High Capacity RNA-to-cDNA Master Mix and High Capacity RNA-to-cDNA Kit are for first strand cDNA synthesis, TaqMan RNA-to-CT 2-Step Kit and Power SYBR Green RNA-to-CT 2-Step Kit are for screening a large number of targets from the same sample.
AB's other soon-to-be available kits include the TaqMan RNA-to-CT 1-Step Kit (to be released April 2008) and Power SYBR Green RNA-to-CT 1-Step Kit, both one-step workflows with reduced hands-on processing.
Life science microscope
Microscopy specialist Olympus has introduced its new Optigrid M structured illumination system designed to compliment its life science microscopy range.
Optigrid M gives the user multi-channel fluorescence and 3D/4D imaging, whilst still using standard illumination. Using light emitted from an existing source, the Optigrid M utilises an optical grid mounted on an actuator to project a line pattern onto the specimen.
"The Optigrid M is a cost efficient system for expanding the imaging capabilities of new or existing microscopes without taking up valuable laboratory space," Olympus said.
"The system offers confocal-like image quality with the Optigrid M integrating quickly and easily with Olympus BX2, IX2 and MVX10 microscopes."
Once a line pattern is projected, the grid is then moved to the grid lines so that three grid movements result in one optical section. The structured illumination process returns a strong signal wherever focus is sharp and a weak signal where focus is soft.
As the Optigrid M slider can be inserted into the field diaphragm slot of a standard illuminator on various Olympus microscopes, wavelengths available from the illumination system from UV to IR can be used.
Genotoxicity screening
UK-based biotechnology company Gentronix has launched its GreenScreen HC - a human cell-based genotoxicity screening assay used in drug discovery programmes during lead compound optimisation and candidate selection.
Now available with an S9 protocol to detect genotoxic metabolites, the assay uses a standardised 96-well microplate format. The assay uses the test compound Green Fluorescent Protein (GFP) reporter cells, which are combined with S9 for a 3 hour exposure period.
After exposure, cells are washed to remove the S9 and test compound and then allowed a further 45 hour recovery incubation. Cell viability and GFP fluorescence data are assessed using flow cytometry.
"Potential pharmaceutical compounds which only present a genotoxicity hazard after metabolism, usually by the liver, are known as pro-genotoxins," explained Getronix.
"The utility of GreenScreen HC has now been extended to detect pro-genotoxins as well as all common mechanistic classes of genotoxin including mutagens, clastogens, aneugens, as well as both topoisomerase and polymerase inhibitors."
Minimal investment in early genotoxicity screening delivers major time savings, avoids unnecessary animal testing and prevents costly late stage failures of lead drug compounds through early detection of genotoxic potential.
Combining exceptional levels of specificity and sensitivity, GreenScreen HC also correctly identifies non-carcinogenic compounds known to give misleading positive results in other in vitro genotoxicity assays.
Lara add-on
Fellow UK-based lab tool makers, Radleys have introduced a new option for its Lara Controlled Laboratory Reactor (CLR) system and Laboratory Reactors that will allow early stage crystal morphology evaluation.
The company's split jacket laboratory reactors with windows for in-process crystal morphology studies are a modern take on traditional methods that use video microscopy as the technique of choice for non-invasive monitoring of particle shape, shape and quantity in process.
The jackets incorporate a flat, optically clear window for use with video microscopy that opens the way to accurate particle characterisation.
This enables early stage evaluation and resolution of process issues, thereby reducing process costs and avoiding the need for repeat batches.
The inclusion of an optical window ensures that the clearest possible image is obtained as particles are not obscured by the depth of the thermofluid within the jacket or the extra glass wall.
Traditionally, fixing a flat optical window has involved 'cementing,' which can either compromise the vessel's chemical resistance or prevent the vessel from being annealed to relieve the stress created during manufacture.
Radleys' method of construction allows complete annealing of the finished vessel after manufacture. The window is therefore guaranteed to be stress free and vessel strength or safety is not compromised. Distortion to the internal surface is also minimised preventing eddies (dead zones) forming close to the internal wall.
By stopping the flow of thermal fluid through the top half of the reactor, Radleys split-jacket reactors maintain a cooler internal surface than traditional reactor vessel designs.
This technology reduces the incidence of crystalline deposits baking onto the inside of the vessel, above the surface of the liquid, improving yields and cutting down on time lost in cleaning between reactions.
