DMI GCMS with OPTIC inlet

GC analysis of dirty sample extracts and even row samples is now possible with Difficult Matrix Introduction. No expensive and time consuming cleanup is required with this technique.

Difficult matrix introduction (DMI) is a technique that employs a micro vial to hold the sample; this is then placed in a liner and loaded into the OPTIC inlet. Low sample volumes, and solids, can be placed in the micro vial and the analytes are directly transferred onto the column. A large sample volume may also be introduced and the solvent vented at a low temperature before transfer, as in a large volume injection. The inlet is taken to a final temperature, calculated using Selective Exclusion, where the target analytes are transferred onto the column but the sample matrix is retained within the glass micro vial. The liner is then exchanged, manually or automatically, for a new liner/micro vial containing the next sample. The liner can be re-used but the micro vial is disposed of after use. Since contaminants are not able to build up in the system, the need for the clean up of crude extracts, and instrument maintenance, are reduced.

  • Ability to analyse sample by directly introducing the matrix or extract into the injector - little if any sample prep is involved
  • Liquid or dirty solid samples contained in a microvial which is inserted in an injector liner
  • Desorption from sample directly onto head of the GC capillary column - fewer steps involved, less opportunities for analyte losses
  • Solvents can be removed by venting under controlled conditions
  • Compounds of interest can be transferred onto the column using the lowest possible final temperature - limits pyrolyzing of matrix
  • Involatiles from the matrix are kept in the microvial which is disposed of after use - liner can be re-used
  • Automation can be done with LINEX

Check manual DMI analysis of ink ondmi example

DMI steps:
DMI sample introduction for gas chromatography