Chromatography Forum

Hi scientists,

I have exam so please help me. Now, what is the different between ( certified reference material) and reference materials ?.

My examiner will ask did you use reference material ?

Ok, at the start of my work, i have three bottle ordered from sigma Aldrich for three cmpounds ( insecticide ) its purity is written like 99 % , 95 % , 99% . All i do i prepare my stock like ( 1 g in 100 ml methanol ) now i have 10,000 mg/l stock solution of my compound then i diluted to make my working standards.

Is this called reference standard or certified reference standard. Shall i said yes i used reference standard or what i say ? i really confuse but i think the certified standard is ready prepared standard like 100 ppm from my compound that come through several authority , iso etc , but what i did called .

sorry i talk a lot but u hope u help me..

By the way i need any thing help me understand the (( the quality control people mind )) what type of question they will ask ,, i am in my Master ohh.



I am using HPLC , AND I ONLY PREPARE MY STOCK AS I SAID PREVIOUSLY
thanks

This may help:
http://www.edqm.eu/site/handling_and_us ... 878-2.html

This may help:
http://www.edqm.eu/site/handling_and_us ... 878-2.html

Yipes - what language is that in? And people are supposed to understand all that?

We've asked our QA about such stuff before, and whenever we dig deep, we end up with way more questions and answers....

If it is a certified reference material it will include a certificate. An example from NIST:
https://www-s.nist.gov/srmors/certifica ... 9445f506b2

Note that while the reference material may be certified it is not necessarily certified for all components. An example from NIST is a fish reference material (can't recall the number) that is certifed for some pesticides and PCB congeners but only has reference values for others. The excluded compounds did not meet the requirements for certification.