Silica compounds polypeptides

It is notable that small peptides were retained on a cross-linked PEI column [37] but polypeptides over 20 residues were weakly retained or not at all. Possibly, small peptides were able to penetrate into the depth of the bonded phase while larger peptides could not. These packings were more useful for the separation of oligonucleotides, i.e. more acidic compounds. Lawson et al. [39] have shown the applicability of PEI-silicas for assessing the purity of precursor blocks, monitoring the chemical synthesis and isolating reaction products after synthesis. 

Silica gel Alcohols, aldehydes, alkaloids, amines, amino acids, amphetamines, antibiotics, antioxidants, barbiturates, carbohydrates, flavonoids, herbicides, heterocyclic compounds, hydrocarbons, indoles, insecticides, ketones, lipids, nitro compounds, organic acids, peroxides, pesticides, phenols, plasticizers, polypeptides, steroids, terpenes, unsaturated compounds, vitamins. 

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