007-5MS

Boiling point column, low bleed characteristics for GC/MS use: hydrocarbons, solvents, waxes, etc.,

Traditional polysiloxane-type GC stationary phases degrade at elevated temperatures. The degradation process is well documented and consists of the thermal rearrangement of the siloxane backbone to produce cyclic groups. These groups are volatile and elute from the column as column 'bleed'. The silphenylene units within the 007-1MS backbone act as heat sinks and limit the formation of the cyclic groups normally associated with polysiloxane degradation.

Silphenylene/polysiloxane phase unit.

007-5MS Silphenylene Baseline Bleed

A typical 007-5MS baseline bleed is shown above in Figure 2. The mass spectrum of the baseline bleed is shown below

007-5MS Silphenylene Mass Spectrum. Note the low abundance of key ions.

While a typical methylpolysiloxane bleed spectrum shown below in Figure 4. yields high abundance's of ions with m/z 207, 281, 355, the mass spectrum of the 007-5MS silphenylene column (above, Fig. 3.) yields significantly lower abundance of these ions. Additionally, it is apparent from Figure 3 that there is a reduction in the total number of ions resulting in "cleaner" spectrum and less background interference.

Typical Methylpolysiloxane Mass Spectrum

007-5MS Silphenylene Polysiloxane columns are available in all standard column I.D.'s and in limited column lengths. The film thickness ranges are noted in the chart below.

Specifications: