Controlled Pore Glass (CPG) has been widely used as a solid support for oligo synthesis for several decades. LGC, Biosearch Technologies’ has perfected CPG manufacture for maximum oligo purity and yield. Our advanced CPG production techniques improve control of particle size and shape, pore size, pore volume, and specific surface area. These physical parameters influence solution exchange behaviour, ligand loading and distribution, and reaction kinetics to increase the efficiency, purity, and reproducibility of syntheses.

We have developed proprietary chemical attachment procedures to further optimise ligand distributions, providing increased accessibility to synthesis reagents and washing solutions and facilitating even better oligo yields and purities. Furthermore, process refinements and proprietary assays have been developed to minimise the troublesome “N-1” impurity levels in an oligo synthesis.

LGC, Biosearch Technologies’ Prime CPG is considered to be the gold-standard solid support used in all sectors of the market. Our collaborative process has resulted in solid supports that are optimised for the synthesis of the latest therapeutic oligo classes including LNA, delivery enhancing lipid ligands, siRNA and Spiegelmers.

Our CPG RNA solid supports are available in a variety of pore sizes and functionalised nucleoside loadings. Which pore size and loading required is dependent on the length, complexity and application of the oligo.

In general, large scale oligo synthesis for therapeutic applications requires high loaded 500-600 Å and small to medium scale synthesis for diagnostic or research use require higher pores sizes.

Aside from Prime CPG, many research-use CPG products are also available which originated from the legacy portfolios, including SynBase™ CPGs. These CPGs are manufactured from the same glass as the Prime products, using similar processes, but generally offered in smaller pack sizes for research purposes.

SynBase RNA CPG loading options

Linkers

In our RNA CPG products, the long-chain alkyl amino succinyl linker (CNA) is the most common (denoted by “CNA” in Prime CPG product names and also used in SynBase products), although the aminopropyl (AMP)-succinyl combination allows for smaller pore sizes (denoted by “AMP” in Prime CPG product names and is the standard linker combination in the non-Prime/SynBase products).

Protection strategies

Nucleobase protection options are similar to those of the RNA Phosphoramidites, i.e. classic (Bz-A, Bz-C and iBu-dG), UltraMILD (phenoxyacetyl (Pac)-A, acetyl (Ac)-C, and iso-propylphenoxyacetyl (iPr-Pac)-G), or Fast utilising Ac-C, Bz-A and dimethylformamidine (dmf)-G.

There are some differences in 2’-OH protection options:

Isomers

The standard stereochemistry is the D-diastereoisomer.