Author: Christopher Baker
Affiliation: Scientific Instrument Services
Sample vials for use in direct probes have been made of a variety of materials including aluminum, gold, quartz and Pyrex glass. Quartz, gold and aluminum vials are fairly expensive and therefore many users elect to reuse the vials after cleaning between samples. This is time consuming and care must be taken to insure that the vials are completely clean to eliminate cross contamination.
Glass has been widely used for sample vials because the vials are inexpensive enough to make them disposable. The glass vials, however, can be difficult to use because they are fragile and are susceptible to breaking when inserting or removing the vials from the probe. The small diameters of straight sample vials also makes loading a sample troublesome.
Flared glass sample vials provide advantages over the standard straight glass sample vials. The flared end of the vial makes loading a liquid sample much easier since the flare helps guide the syringe needle into the vial. The flared end also makes the vial much stronger so that vials can easily be inserted and removed from the end of the probe using tweezers without breaking the glass. Flared vials have been used on most Finnigan MAT instruments for many years, however flared vials of various diameters can be manufactured by S.I.S. for use on other instruments providing glass sample vials which are stronger and make sample loading much easier.
Yttria coated filament at start
Yttria coated filament after 16,000 cycles