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Taking spectra from small sample volumes can be difficult at times. Our 5 mm Microcell Assembly is designed to reduce these difficulties for you. There are three different inserts to choose from, depending on your sample size and requirements. Either spherical bulb capillary tube or cylindrical bulb. Volume sizes are listed in the price list below. You must order the PTFE holder, which holds the inserts in the NMR tube, and the Positioning Rod, which allows you to insert and remove the assembly from the tube. These items are reusable, the inserts are intended for one time use.
Note: this assembly is not recommended for variable temperatur applications because of different thermal expansions of the materials.
Complete with Outer Tube, Teflon Holder, Positioning Rod and one spherical bulb.
Other inserts and extra Spherical Bulbs are ordered separately.
Our large volume microcell inserts are intended for use with probe sizes between 8 and 20 mm.
Selection is either a spherical bulb or cylindrical bulb, depending on your requirements.
For best spectral resolution, choose a size that matches your probe coil height requirements.
• Easier to use than glass alternative
• Can be used with a wider range of solvents
• Use them with existing tubes
• Lower in cost than glass
• Less fragile than susceptibility-altered glass microtubes
Traditionally, sample sizes were 3-5 times the height of the probe Rƒ coil. All magnetic field distorsions caused by magnetic susceptibility discontinuities at the upper air-sample and lower glass-sample interfaces were far from the sensitive probe Rƒ coil region.
Small samples diluted to larger traditional volumes (1 ml) yield poor NMR spectra in high field spectrometers.
Through magnetic susceptibility matching of the sample solvent, Doty Susceptibility Plugs allow the sample to be substantially concentrated by extending out the air-sample/glass sample interfaces far enough away from the Rƒ coil region to remove the magnetic field distorsions.
Doty Susceptibility Plugs are provided as sets ot two. Positioning rod and collar are provided as a set and ordered separately from the plug set. The upper face of both plugs has a thread that lets you firmly attach a positioning rod. The upper plug is held in the tube by the positioning rod. The rod, in turn, is held by a collar that rests on top of the tube. A special sealing collar (equipped with two o-rings) can be ordered separately for long term storage of samples where solvent evaporation can alter results. The sealing collar is used to replace the standard positioning collar on the rod.
With our 5 mm Coaxial Inserts, you can switch between three unique sample ratios.No other 5 mm coaxialset-up offers this much variety in sample volumes.
You can also use the 5 mm Coaxial Insert in Variable Temperature experiments. It's Pyrex insert and spacer remain compatible with the outer tube, unlike systems using plastic parts.
Use the insert with 7 inch thin wall 5 mm tubes 506-PP or higher in quality. Order an insert and two spacers separately or order a complete set with insert joined at the bottom to a 507-PP outer tube.
For external locking or locking of larger samples, you have a choise of three sizes.
Our External Reference Coaxial System is perfect to isolate your reference solution from sample. Each insert fits with precision into the outer tube. The flat bottom forces the reference solution upwards between the inner and outer tube which forms a thin film of about 50 µl. You can chose 3, 5 or 10 mm diameter size.