Affinity purification

Stereomicroscope The new Carl Zeiss stereomicroscope Stemi 2000-CS allows the user to view the sample whilst other observers view the procedure by video. Greenough type stereomicroscopes create their stereo effect by having separate light paths set at different angles, one for each eye. However, when video or photomicrography is being carried out most stereomicroscope systems remove light from one of the light paths within the body of the microscope, leaving only one viewing path. This can make it difficult to demonstrate a process to video viewers. The problem can be overcome with the Stemi 2000-CS, which splits light from the right hand viewing path 50:50 between the viewer and the camera port, whilst also adjusting the brightness in the left hand path to balance the light levels between the eyes. The equipment can be used with a range of accessories. Circle letter a on reader reeponse card. temperature cycler from Stratagene is the newest addition to the Robocycler temperature cycler product line. The Robocycler Infinity cycler combines features and benefits of the standard RoboCycler temperature cycler with the added flexibility of interchangeable blocks. Unlike conventional temperature cyclers that have only one block for PCR denaturation, annealing and extension steps and must ramp a single block's temperature up and down, every RoboCycler temperature cycler features four programmable thermal blocks and a robotic arm that rapidly moves samples from one pre-equilibrated block to another. This allows a 30% reduction in sampling time. Another key feature of the RoboCycler system is a _+ 0.1°C well-to-well temperature uniformity. Easily interchangeable blocks add versatility while an independent hot top assembly allows oil-free PCR amplifications. Circle letter b on reader response card. A new reagent that now enables the accurate determination of protein molecular weights between 10 kDa on a single gel has been developed by Arnersham Life Science. The Full Range Rainbow TM coloured protein molecular weight markers are visible during electrophoresis, enabling easy monitoring of experimental progress. The bands are also visible when transferred to blotting membranes, so the size estimation of unknown proteins is also straightforward. Developed using recombinant standard proteins, rather than naturally-sourced proteins, to ensure tighter bands, the molecular weight range ensures that a ladder of evenly spaced, discrete bands is obtained. Supplied in ready-to-load format, the 10 marker proteins are each labelled with a differently coloured dye, enabling simple visual identification. The markers provide sufficient material to run 50 mini …