Tijana Vasiljevic

6 Questions 12 Answers 0 Followers

Questions related from Tijana Vasiljevic

LC/MS and GC/FID give different answers on fatty acid amounts for the same sample?

Hi everyone! I am testing free fatty acid in coconut oil and coconut oil treated with microbial cells. For the GC/FID I am using a methylation (methanolic HCl at 90 degrees celsius) approach to...

16 August 2023 5,607 8 View

Dilute and shoot for free fatty acid analysis?

Hi everyone, I am looking to develop a method for analysis of free fatty acids in oil (coconut, canola, olive... etc.). I've noticed that there are some methods out there that simply use...

05 June 2023 2,181 1 View

Can hyaluronidase completely breakdown hyaluronic acid of lower molecular weight?

Hi all, I am using hyaluronidase from sheep testes for breakdown of hyaluronic acid and analysing by HPLC. Is it possible for hyaluronidase to perform more "destruction" to hyaluronic acid of...

05 April 2023 1,459 0 View

Surfactant carryover in LC/MS?

Hi everyone, I am trying to develop a LC/MS method for the analysis of 2 anionic surfactants. While the method seems to be working fine, I am facing an odd carryover issue. - We are using a...

14 December 2022 4,333 11 View

Injections of QC standard yield increasing areas in negative ionization mode (LC/MS/MS)?

Hi all! I am using a Waters-TQS micro (LC/MS/MS) in negative ionization mode (MRM) to analyse a few compounds. When doing QC injections (i.e., repeated injections from same vial of standards at a...

01 December 2022 8,142 4 View

Area of derivatized analyte greater than its pure standard?

Hi everyone! I am doing a derivatization reaction for conversion of formaldehye into a more friendly GC analyte, diethoxymethane. The reaction is done in a 10 mL headspace vial, and a sample of...

20 October 2022 884 6 View