Hello,

I prefer to inject an n-alkane (not alkene) calibration samples separately randomized in my analysis sequence. So you can better adjust the right concentration of the alkane sample. If you add alkanes to your analysis samples directly, peak overlapping may occur.

Regards

Detlef

I routinely use RI (n-alkane; calculated for compounds of interest on two different GC phases) as one of the criteria for elucidation of identities. As Detlef mentioned above, it is problematic to add mix of alkanes in sample for the reason of co-elution of alkane and compounds of interest. But you can inject n-alkanes mix with authentic standards of compounds of interest.

Regards

Tanoj

HI Mohsen

Practical use of rentention indices in identifcation of compounds is documented /explained in reference books. Please do check out the following link and reference:

1. The LRI and Odour Database (http://www.odour.org.uk/)

2. Lucero et al (2009). A Retention Index Calculator Simplifies Identification of Plant Volatile Organic Compounds. Phytochemical Analysis 20: 378-384.

Regards

Tanoj