Dendrimers and their applications.

Dendrimers are symmetric molecules; their size is within the nanoscale. Its structure is usually homogeneous and monodisperse; they are composed of a nucleus and several layers. The number of layers that the dendrimer has defines its generation. There are different types of dendrimers. The synthesis of these macromolecules is carried out following steps of growth and activation, and organic reactions are required to obtain their branched structure. Although size is essential, the determining factor of toxicity in dendrimers is the charge of the surface; it has been found that the higher generation dendrimers and the cationic ones are the most toxic compared to the lower generation anionics that evaluated at low concentrations did not show any toxicity. The dendrimers will favor the pharmacokinetics of a drug through the dendritic structure, the generation of the dendrimer to be used, the intramolecular interaction force between the adjacent functional groups in the dendrimer, the conditions of the environment such as pH, solvent polarity, strength ionic, saline concentration or presence of counterions, among others 4. Due to dendrimers' size and surface composition, the use of dendrimers in drug delivery has been increasingly studied. There are different interaction mechanisms between drugs in dendrimers, and these can be broadly divided into simple encapsulation, electrostatic interaction, and covalent bonds 5. The use of dendrimers in ocular administration has greatly impacted the complexity of this administration route. Gene therapy has also benefited from the emergence of these molecules as it facilitates targeted therapy. [ABSTRACT FROM AUTHOR]