Experimental and theoretical investigations in stimuli responsive dendrimer-based assemblies

Abstract

Stimuli-responsive macromolecular assemblies are of great interest in drug delivery applications, as it holds the promise to keep the drug molecules sequestered under one set of conditions and release them under another. The former set of conditions could represent circulation, while the latter could represent a disease location. Over the past two decades, sizeable contributions to this field have come from dendrimers, which along with their monodispersity, provide great scope for structural modifications at the molecular level. In this paper, we briefly discuss the various synthetic strategies that have been developed so far to obtain a range of functional dendrimers. We then discuss the design strategies utilized to introduce stimuli responsive elements within the dendritic architecture. The stimuli itself are broadly classified into two categories, viz. extrinsic and intrinsic. Extrinsic stimuli are externally induced such as temperature and light variations, while intrinsic stimuli involve physiological aberrations such as variations in pH, redox conditions, proteins and enzyme concentrations in pathological tissues. Furthermore, the unique support from molecular dynamics (MD) simulations has been highlighted. MD simulations have helped back many of the observations made from assembly formation properties to rationalized the mechanism of drug release and this has been illustrated with discussions on G4 PPI (Poly propylene imine) dendrimers and biaryl facially amphiphilic dendrimers. The synergy that exists between experimental and theoretical studies open new avenues for the use of dendrimers as versatile drug delivery systems.

Electrogenerated chemiluminescence reactions between the [Ru(bpy)3]2+ complex and PAMAM GX.0 dendrimers in an aqueous medium

“…Special expectations are associated with the use of these polymers as carriers of biologically and medically important molecules [1][2][3][4][5][11][12][13][14][15][16][17][18], above all of oncologic drugs [11][12][13][14][15][16][17]. In addition, it has been recently shown that these globular branched polymers have a great potential as anti-amiloydogenic agents [19,20], and as interferents in the formation of prion materials [21].…”

Multi-Stimuli-Responsive Polymer Materials: Particles, Films, and Bulk Gels

“…Stimuli‐responsive particles that exhibit changes in dimension, structure, or aggregation state in response to an internal or external stimulus have become a rapidly developing category of stimuli‐responsive materials due to their diverse range of applications, particularly in drug delivery 91–102. Multi‐stimuli‐responsive particles that respond to a combination of three or more signals represent particularly promising candidates, as demonstrated by scientists and engineers in various fields of physics, chemistry, biology, and medicine.…”

Sharp‐pH‐Sensitive Amphiphilic Polypeptide Micelles with Adjustable Triggered pHs by Salts via the Hofmeister Effect

“…Stimuli‐responsive polymers, especially pH‐responsive nanoparticles, are intelligent system that can be widely applied in different areas . Most stimuli‐responsive polymers are based on the self‐assembly of polymeric molecules for various nanostructures such as liposomes, dendrimers, and micelles . The observed response shown in macroscale is a consequence of the conformational change of polymer molecules within the polymer system.…”