Reversed-phase monoliths prepared by UV polymerization of divinylbenzene.

Many different techniques have been developed to prepare monolithic materials specifically for chromatographic techniques. The two most popular polymerization techniques being thermal or via ultra violet (UV) light. Whereas thermal polymerization is easily employed for a whole variety of monomer and porogen systems, UV polymerization has been limited to methacrylate-based systems, and styrenic systems have been avoided due to their strong absorbance at low wavelengths.

New monolith technology for automated anion-exchange purification of nucleic acids.

Synthetic nucleic acid analysis often employs pellicular anion-exchange (AE) chromatography because it supports very high efficiency separations while offering means to control secondary structure, retention and resolution by readily modifiable chromatographic conditions. However, these pellicular anion-exchange (pAE) phases do not offer capacity sufficient for lab-scale oligonucleotide (ON) purification. In contrast, monolithic phases produce fast separations at capacities exceeding their pellicular counterparts, but do not exhibit capacities typical of fully porous, bead-based, anion-exchangers.

Separation of inorganic anions on a high capacity porous polymeric monolithic column and application to direct determination of anions in seawater.

A commercially available 4.6 mm id x 50 mm polymethacrylate-based monolithic strong anion exchange column (ProSwift SAX-1S) designed for the separation of proteins has been successfully used to separate small inorganic anions in the presence of a seawater sample matrix. Using a hydroxide eluent with suppressed conductivity detection the ion exchange capacity of this column declined over time; however, using KCl as the eluent, the column performance was stable with a capacity of 530 microequiv.

Polymerised bicontinuous microemulsions as stationary phases for capillary electrochromatography. Effect of pore size on chromatographic performance.

Monolithic columns for capillary electrochromatography (CEC) were prepared by in situ polymerisation of bicontinuous microemulsions containing butyl methacrylate. The resulting monoliths were found to be permeable to mobile phase flow and their behaviour as CEC stationary phases was investigated. It was found that the monoliths were able to separate a simple test mixture of phthalates, but that efficiencies were low.