Properties and Bioapplications of Amphiphilic Janus Dendrimers: A Review

Abstract

Amphiphilic Janus dendrimers are arrangements containing both hydrophilic and hydrophobic units, capable of forming ordered aggregates by intermolecular noncovalent interactions between the dendrimer units. Compared to conventional dendrimers, these molecular self-assemblies possess particular and effective attributes i.e., the presence of different terminal groups, essential to design new elaborated materials. The present review will focus on the pharmaceutical and biomedical application of amphiphilic Janus dendrimers. Important information for the development of novel optimized pharmaceutical formulations, such as structural classification, synthetic pathways, properties and applications, will offer the complete characterization of this type of Janus dendrimers. This work will constitute an up-to-date background for dendrimer specialists involved in designing amphiphilic Janus dendrimer-based nanomaterials for future innovations in this promising field.

Keywords: amphiphilic Janus dendrimers; biomedical applications; dendrimers; dendrimersomes; glycodendrimersomes.

Figure 3

Examples of particular Janus dendrimers (a) fluorinated JDs [77]; (b) Janus metallodendrimers [93]; (c) sequence-defined JGDs [92].

Figure 1

Schematic representation of an amphiphilic Janus dendrimer.

Figure 2

A dipolar dendritic molecule designed by Fréchet group [65] The broken symmetry structure of Janus dendrimers and their self-assembly ability to form various complex molecular architectures give them the flexibility and versatility to be applied in different fields such as biomedicine (especially as nanocarriers) [63], molecular imaging, especially MRI (magnetic resonance imaging) [74,75,76,77], optoelectronics [78,79,80,81,82], catalysis [83], ionic liquids [84,85], and thermal actuators [86].

Figure 4

Synthesis of amphiphilic Janus dendrimers (a) chemoselective coupling; (b) heterogeneous double exponential growth; (c) mixed modular approach; (d) secondary growth of the dendron from the broken structure of a conventional dendrimer.

Figure 5

Biomedical applications of amphiphilic Janus dendrimers.

Figure 6

G4 JDs as stabilizers in media milling and dry-state processing of pharmaceuticals [106].

Figure 7

Light-responsive dendrimersome vesicle platform. (a) Example of photocleavable Janus dendrimer; (b) Representation of light-induced release of attached protein cargo of the outer JD vesicle layer [153].