Tentatively Identified Compounds - TICs

The following methods may be specified for the reporting of Tentatively Identified Compounds.


1.    "PLUS TIC's"

    Run the automated Tentatively Identified Compound Procedure in the same manner as First Class i.e. up to 30 TIC's can be reported (where peak areas are greater than 5% of internal standard).  Semi-quantitated against nearest internal standard.

2.    "Compound name by Search"

    Use the automatic search procedure to look for the nominated compound (using the NIST library entry reference spectra if possible, or subset of appropriate qualifying ions).

3.    "Compound name by CCC method"

    An additional standard solution of the target compound will be analysed prior to the sample(s) for calculation of the response factor used in the quantitation.

4.    "Compound name by five-point"

    A five-point initial calibration of standard solutions will be carried out and then daily CCC's analysed to confirm continued linear performance.  Concentrations will be determined using the CCC response factor.


Notes:

1.    It may not be possible to do the search method if an NIST entry is not available.

2.    It may not be possible to use the CCC method if a reference material is not readily available, nor if the requested compound is not amenable to the current method of analysis employed.

3.    It may not be possible to use the five point method if the compound is not easily amenable to a linear range similar to that of existing target compounds.

4.    The assignment of non-target compounds by the automatic TIC search procedure can be unreliable.

5.    Use of the search method may not always be successful at all concentrations and in the presence of interfering compounds.

6.    Assignments made may be incorrect due to isomer similarities.

7.    The method will not have been validated for the compound and typical recovery data will not be available.  Therefore the recovery of non-target compounds can at best only be estimated and for some compounds may be expected to be very low