Quantification of blank injection

Discussions about HPLC, CE, TLC, SFC, and other "liquid phase" separation techniques.

2 posts Page 1 of 1
Hi i have a question regarding the blank injection for HPLC SEC.
Some guidelines prescribe to use a blank at the beginning to see if there is a stable baseline and no unusual peaks. From what limit can you say there is an unusual peak? is there quantification described in the USP or Ph. Eur. or some other guideline?

All help is welcome, thank you in advance
I am unaware of any "limits" in any guidelines as injecting a true blank at the start of any method (note: a "true" blank = the mobile phase at initial conditions) is part of following good chromatography fundamentals. Blanks should be included in all methods, esp quant, but all methods. The "blank" injection demonstrates that the mobile phase and injection solution are the same, with almost no measurable "peak" observed on the baseline (the 'peak' will of course depend on the type of detector used and configuration, which must be defined). *By UV, you should still see a small peak which corresponds to the Tzero time from the change in pressure caused by the make/break of the injection valve (normal). No other peaks should be visible.
2 posts Page 1 of 1

Who is online

In total there is 1 user online :: 0 registered, 0 hidden and 1 guest (based on users active over the past 5 minutes)
Most users ever online was 1117 on Mon Jan 31, 2022 2:50 pm

Users browsing this forum: No registered users and 1 guest

Latest Blog Posts from Separation Science

Separation Science offers free learning from the experts covering methods, applications, webinars, eSeminars, videos, tutorials for users of liquid chromatography, gas chromatography, mass spectrometry, sample preparation and related analytical techniques.

Subscribe to our eNewsletter with daily, weekly or monthly updates: Food & Beverage, Environmental, (Bio)Pharmaceutical, Bioclinical, Liquid Chromatography, Gas Chromatography and Mass Spectrometry.

Liquid Chromatography

Gas Chromatography

Mass Spectrometry