Nacalai provides HPLC and SFC columns with alternate selectivity for difficult-to-separate compounds. The core-shell Cosmocore Cholester HPLC column can baseline separate 25-OH vitamin D<sub>2</sub> and D<sub>3</sub> metabolites and their epimers in isocratic reversed-phase condition. The same Cosmocore Cholester HPLC column can also detect Δ-8 THC and Δ-9 THC and metabolites. Additionally, we provide SunShell HPLC/SFC columns in the US. Free column screening is available in our San Diego lab.