Biomedical polymers isomers

Both L- and o-lactic acid stereoisomers are naturally occurring however, most of the lactic acid in nature is L-type or sometimes racemic. The fact that lactic acid that is produced in the human body is in the L-enantiomeric form and the interest in the biomedical applications of this polymer have led both research and production to concentrate on L-lactide or OL-lactide polymers [16-18]. The o-isomer does not have many applications, except for use in particular medicinal chemicals. 

The attachment of functional groups to polymers is frequently the first step towards the preparation of speciality polymers, for example, for biomedical applications or as supported reagents. In the latter category particularly, polymers containing the m- and />-isomers of chloromethylstyrene are widely used and the syntheses of many functionalized polymers based on these starting materials have been described. ... 

Similar to PGA, polymers obtained from the synthesis of lactide have also been widely used in the biomedical field. As lactide is a chiral molecule, polymeric lactide exists as three isomers L-lactide, o-Iactide, and meso-lactide. Therefore, four different types of polylactic acid are available poly(L-lactic acid), poly(D-lactic acid), poly(DL-lactic acid), and mesopolylactic acid. 

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