Chromatography Forum

hi,
i'm running sunscreen which required me to achieve resolution at least 2.5between Avobenzone and Octinoxate peak. the mobile phase used r 60% 0.1% Aqueous Phosphoric Acid, and 40% Methanol, Thermo Scientific Hypersil Gold, 5micron 3.0 mmx150 mm, 0.4ml/min,254nm. i'm facing a problem to separate those two actives...can sumone suggest what kind of column or Mobile phase is suitable to separate both actives?? :

Try to do with Thermo Scientific application.
http://www.analiticaweb.com.br/newslett ... orbers.pdf
For summary,
Column : Hypersil Gold, 1.9 um, 100 x 2.1 mm
Mobile Phase A : Water, B : Acetonitrile
Isocratic : 40:60
Flowrate : 1.0 ml/min
Detector : PDA Scan 200-500 nm, Discrete 313 nm
Column Temp. : 45 degree C

Best Wishes
Jetjamnong