Synthesis and micellization properties of triblock copolymers PDMAEMA-b-PCL-b-PDMAEMA and their applications in the fabrication of amphotericin B-loaded nanocontainers

Abstract

In this study, we report the synthesis of PDMAEMA-b-PCL-b-PDMAEMA via ATRP starting from two dibromide-end polycaprolactone (PCL) of 2 and 10 kDa. The copolymerization was confirmed by nuclear magnetic resonance and gel permeation chromatography. The micellar properties of copolymers with different compositions were studied at pH 5.0, 6.0, 7.0, and 7.5. According to results, properties such as critical micellar concentration (CMC), hydrophobicity of micelle cores, and particle size strongly depend on the length of PCL. The pH shows an important effect on the size of the colloidal aggregates. Micelles obtained from copolymers with the lowest polymerization degree of both segments showed to be more appropriate for the encapsulation of amphotericin B (AmB).

A pH-responsive drug delivery matrix from an interpolyelectrolyte complex: preparation and pharmacotechnical properties

“…In Figure 6A, EUE presents the lowest moisture absorption because DMAEMA units with low protonation degree present a hydrophobic character, as observed from the insolubility of PDMAEMA in alkaline aqueous solutions (Diaz, Perez, 2015). This behavior agrees with the early reported application of EUE as a protective agent of water-sensitive substances (Bley, Siepmann, Bodmeier, 2009).…”

“…Not all amine groups on EUE are ionized and interacting electrostatically with carboxylate groups owing to their weak basic characteristic (Moustafine, Zaharov, Kemenova, 2006;Diaz, Perez, 2015) and their trapping into hydrophobic polymer domains that further decrease their basicity (Moustafine, Kemenova, Van den Mooter, 2005). Hence, a marked reduction of signals at 2776 cm −1 to 2884 cm −1 in comparison with those of the physical blend and EUE indicates that non-charged amine groups on SIPEC are almost extinguished.…”

Hydrophobic cellulose fibers via ATRP and their performance in the removal of pyrene from water

“…Two surface initiators with different grafting density were synthesized based on protocols previously published . Paper filters were cut into square pieces of approximately 0.5 cm × 0.5 cm, and thoroughly washed with distilled water, ethanol, and acetone to remove any interfering compounds.…”

“…Atom transfer radical polymerization (ATRP) is one of the most versatile and powerful techniques that allows obtaining polymers with controlled composition, molecular weight, and dispersity. The essential feature of ATRP is the equilibrium between a low concentration of active propagating species, and a larger number of dormant chain ends, via an inner sphere electron transfer process promoted by a transition metal complex . In fact, surface initiated (SI) ATRP has shown to be an efficient technique to graft cellulose materials with different polymers, to give some examples: polystyrene and poly( N , N ‐dimethylamino‐2‐ethyl methacrylate) have been grafted to cellulose nanocrystals, whilst poly (methyl methacrylate)‐ block −2‐hydroxyethyl methacrylate has been grafted to cellulose fibers in paper sheets …”

α-Tocopherol loaded thermosensitive polymer nanoparticles: preparation, in vitro release and antioxidant properties

“…Synthesis of dibromide ended PCL: Br-PCL-Br was synthesized using a protocol previously published [19] . In a typical procedure for PCL Mn=10 KDa, 5 g of diol-ended PCL (0.35 mmol) was dissolved in 50 mL of anhydrous dichloromethane with 500 μL of triethylamine (3.5 mmol) whereas stirring under argon atmosphere.…”