Small bioactive molecules

Recently, the recovery and purification of small bioactive molecules from complex media has gained a new interest. Small bioactive molecules comprise a large variety... 

The chirality of DNA was applied to selective separation. A DNA aptamer as a new target-specific chiral selector for HPLC was investigated by Michaud et al. [119,120]. They showed that a tailor-made chiral stationary phase based on a DNA aptamer with known stereospecific binding for the D-enantiomer of the oligopeptide, arginine-vasopressin, exhibits enantioselectivity between the d- and L-peptides. This DNA-based target-specific aptamer chiral stationary phase provides a powerful tool for the resolution of small (bioactive) molecule enantiomers. 

A new approach termed Biology Oriented Synthesis (BIOS) has been developed recently by Waldmann et alf This approach is based on the structural similarity between small bioactive molecules on the one side and their receptors, that is proteins, on the other side as well as on the complementarity of both. BIOS employs compound classes from biologically relevant regions of chemical space, for example natural product or drug space, to select scaffolds as starting points for the design and synthesis of small focused libraries with limited diversity. In this respect BIOS provides a conceptual alternative to other approaches... 

Ziegler, S., Pries, V, Fledberg, C., and Waldmann, FI. (2013) Xarget identification for small bioactive molecules finding the needle in the haystack. Angew. Chem. Int. Ed., 52, 2744-2792. 

The Biological/Pharmacological Problem Discovering Small Bioactive Molecules... 

Since this pioneering work, so many proteins, peptides, small bioactive molecules. Liposomes, surfaces, etc. have been modified by PEGs of various sizes, types, and linkages that the term pegnology is sometimes used to describe work in this field. Here, two PEG-enzymes will be discussed. The first, PEG-adenosine deaminase (PEG-ADA) is designated as an orphan drug by the Food and Dmg Administration. 

Small bioactive molecules and proteins were loaded into polymeric micelles and released after the enzyme-induced disassembly of the a self-assembled structure (Ge et al, 2011 Wang et al, 2010). Similarly, proteins were entrapped in the hollow centre of polymer capsules from where they could be released after enzymatic degradation of the capsule (Itoh et al, 2006). Proteins have also been encapsulated within a polymer directly. The polymer forms a close shell around each individual protein that shell can be enzymatically degraded to restore the activity of the protein (Gu et al. 

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