Tosoh, 0021999, TSKgel NH2-100 DC

The TSKgel NH2-100 DC column is packed with 3 μm silica particles containing 10 nm pores and connects directly to TSKgel reversed phase columns. The DC in TSKgel NH2-100 DC emphasizes this Direct Connect aspect. This column has the same packing material as the TSKgel NH2-100 columns, so therefore shows high retention for hydrophilic compounds/ions. A male-type outlet endfitting enables the direct connection to the screw-type endfitting of a TSKgel reversed phase column. This allows for the simultaneous separation using a linear gradient of an active pharmaceutical ingredient (API) and its counterion without the loss of column efficiency normally experienced when connecting two columns with capillary tubing. The TSKgel NH2-100 DC amino-bonded column stands out by providing much improved chemical stability, a prerequisite for achieving reproducible and reliable results. A novel bonding strategy was adopted to improve chemical stability of the bonded phase. First, the silica is reacted with a trimethylsilane endcapping reagent at a low stoichiometric ratio before reacting residual and accessible silanol groups with trifunctional alkylaminosilane reagent. The resulting bonded phase provides a better safeguard against hydrolysis of the underlying silica.