Nacalai Tesque COSMOSIL 5TMS-MS Guard Column, 5 μm, 4.6 mm I.D. x 10 mm - 38171-71 *OBSOLETE*

COSMOSIL alkyl type columns also include stationary phases with packing materials of C₂₂ (Dococyl group), C₈ (Octadecyl group), C₄(Butyl group) and TMS (Trimethyl group). The order of retention force by hydrophobicity of each packing material is C₂₂=C₁₈>C₈>C₄>TMS. The columns having lower hydrophobicity than C₁₈ or C₂₂ are effective for separation of high hydrophobic compounds and compounds with big difference in hydrophobic. Hydrophobicity of C₂₂ is about the same as C₁₈. However, stereoselectivity of C₂₂ is higher than C₁₈, and so C₂₂ may provide better separation.

Specifications

Packing Material	C22-AR-II	C18-MS-II	C8-MS	C4-MS	TMS-MS
Silica Gel	High Purity Porous Spherical Silica
Average Particle Size	5 µm
Average Pore Size	approx. 120 Å
Specific Surface Area	approx. 300 m2/g
Stationary Phase	Dococyl Group	Octadecyl  Group	Octyl  Group	Butyl  Group	Trimethyl  Group
Bonding Type	Polymeric	Monomeric
Main Interaction	Hydrophobic Interaction
End Capping Treatment	Near-perfect Treatment
Carbon Content	approx. 19%	approx. 16%	approx. 10%	approx. 7%	approx. 5%