ESTD VS ISTD

[amrnasser87]

dear all

iam using ESTD as my basic calculaion but i want to try ISTD in my GC for hydrocarbon analysis

any one could help me to know the advantages and disadvantages of both?

regard
Amr

[GasMan]

Amr,

You do not say if your samples are gas samples or liquid samples. If you are doing gas analysis with a gas sampling valve it is extremely difficult to add an internal standard to a gas mixure, so you are limited to external standard calculation or normalization.

Gasman

[amrnasser87]

Amr,

You do not say if your samples are gas samples or liquid samples. If you are doing gas analysis with a gas sampling valve it is extremely difficult to add an internal standard to a gas mixure, so you are limited to external standard calculation or normalization.

Gasman

i am using gas sample