Question

32. Compare and contrast dendrimers with block copolymer micelles, globular proteins, inorganic nanoparticles in terms of attributes and likely utility in the following applications: (a) drug delivery; (b) homogenous catalysis; and (c) solubilization..

Answer 1

Dendrimers are synthetic macromolecules which is composed of repetitive layers of branching units. These branching units emerges from central core.

Dendrimers are characterised by two Types,

1) By tunable size,

2) By the number of peripheral groups.

Peripheral groups determines the physiochemical properties and functions of dendrimers.

Dendrimers have high multivalency, functional surface and globular architecture with nanometer scale diameter. Due to this property dendrimers have wide range of applications.

The first application of dendrimers is In drug delivery. One of the famous dendrimer is GATG dendrimer. The presence of terminal azide groups In GATG dendrimer makes it efficient to attach with variety of ligands for biomedical relevance. And this dendrimer have an application In drug and gene delivery as an antiviral agent . This is also used for the treatment of neurodegenerative diseases and In diagnosis.

Dendrimers have another application In homogeneous catalysis. In homogeneous catalysis, Non - chiral dendritic transition metal complexes is used. For example, kharasch addition of CCl4 to methacrylate is catalysed by Ni(II); CO/Alkene polymerisation is catalysed by Pd(II) and rhodium catalyzed hydroformylation etc.

The third application of dendrimers is solublization. Dendrimers have potential application In enhancing the solubility of poorly soluble drugs. Because dendrimers have hydrophilic exteriors and interiors also and these both are responsible for its micelle nature and increases the solubility for drug delivery system.