Poly(dl-lactide)-b-poly(N,N-dimethylamino-2-ethyl methacrylate): Synthesis, Characterization, Micellization Behavior in Aqueous Solutions, and Encapsulation of the Hydrophobic Drug Dipyridamole

Abstract

We synthesized a series of well-defined poly(dl-lactide)-b-poly(N,N-dimethylamino-2-ethyl methacrylate) (PDLLA-b-PDMAEMA) amphiphilic diblock copolymers by employing a three-step procedure: (a) ring-opening polymerization (ROP) of dl-lactide using n-decanol and stannous octoate, Sn(Oct)(2), as the initiating system, (b) reaction of the PDLLA hydroxyl end groups with bromoisobutyryl bromide, and (c) atom transfer radical polymerization, ATRP, of DMAEMA with the newly created bromoisobutyryl initiating site. The aggregation behavior of the prepared block copolymers was investigated by dynamic light scattering and zeta potential measurements at 25 degrees C in aqueous solutions of different pH values. The hydrophobic drug dipyridamole was efficiently incorporated into the copolymer aggregates in aqueous solutions of pH 7.40. High partition coefficient values were determined by fluorescence spectroscopy.

Recombinant Amphiphilic Protein Micelles for Drug Delivery

“…28,31,32 As anticipated, the partition coefficients of 1,8-ANS (4.0 × 10 2 ) and thioflavin-T (1 × 10 3 ), which are hydrophobic small molecules that carry a charged group were lower than that of DIP (Figure 3D). …”

“…Similar fluorescence spectral behavior for DIP at pH 7.4 has been noted for PDLLA- b -PDMAEMA diblock copolymers. 31 …”

Modified native cellulose fibers—A novel efficient adsorbent for both fluoride and arsenic

“…On this adsorbent surface, it is the tertiary amine group (-NR 1 R 2 ) on the PDMAEMA chains that is responsible for the binding of anions. The solubility and the charged properties of the grafted PDMAEMA polymer chains are both pHresponsive [36,37]. At lower pH, the tertiary amine group -NR 1 R 2 can be protonated to -NR 1 R 2 H + , and the electric repulsion between -NR 1 R 2 H + can overcome the tendency of the chains to collapse or aggregate in water.…”

Poly(ethylene glycol) Conjugated Poly(lactide)-Based Polyelectrolytes: Synthesis and Formation of Stable Self-Assemblies Induced by Stereocomplexation

“…5,[14][15][16][17][18][19] Among these, the self-assembly of amphiphilic copolymers in a selective solvent above a threshold concentration, referred to as the critical aggregation concentration(CAC), to form polymeric micelles have been investigated extensively for numerous applications, mainly in the biomedical field. [20][21][22] However, polymeric micelles are susceptible to infinite dilution, a condition arising from their administration.…”