Abstract: Increased stability of derivitization agents on the surfaces of packing material used in choromatography is described. In particular, the stability of the organosilanes on silicia surfaces used in chromatography is increased, thereby creating a more durable coating of organosilanes. By increasing its stability, the organosilane entity becomes more resistant to de-bonding and the durability of the underlying surface is enhanced against dissolution. Thus, chromatographic separations are able to be performed at higher and lower pH ranges and higher temperatures. The stability can be increased through attachment of polydentate silanes which are either pre-polymerized and then surface bonded or can be bonded first and then cross-polymerized afterward, yielding a polymerized polycarbosilane backbone that is very stable against hydrolytic cleavage conditions.

Abstract: A fitting provides a means of making a union between a tube and a female fitting with low dead volume and without the use of tools. The fitting is comprised of a tube member that is pressed into the female fitting to automatically remove dead volume. The tube member is pressed into the fitting by a spring with the appropriate tension to hold the tube member against the expected pressure. The fitting also is comprised of a two piece nut assembly. The forward nut compresses a ferrule to create the high-pressure seal. The rearward nut is attached to the forward nut and provides compression and a holding means for the spring.