What is Internal standard HPLC / GC- How to USE

Internal standard how we have to used?

Internal standard

1. Quantities analysis
2. Purpose is
3. Selection process
4. Example is

Quantities analysis main three parts

• External standard
• Internal standard
• Standard addition

External standard

Here we find concentration of amount solution qualified compared response of standard and response sample

Internal standard
Addition of an alytes in a constant amount
to samples and standard during analysis.

Standard addition method

Addiion of analytes in a constant amount to samples to correct for matrix effects
When sample matrix abo contributes to the analytical signal

sample injection volumes

Purpose of Internal standard

To take care of error in sample injection volume in case HPLC /GC

To correct for the loss of analyte
during sample preparation such as,

• Poor extraction

• Poor dervatization
• Co-preciptation with other sample matrix

• Adsorpton on glasswware surface
• Uncontrolled evaporation during sample treatment



What is Internal standard in HPLC

During analysis consert amount of analytes mixed sample or standard call internal standard
Internal standard case Ratio of standard or sample is 1:1 are taken in general practice