0000000000010386
AUTHOR
Benjamin B. Breitenbach
Double stimuli-responsive polysaccharide block copolymers as green macrosurfactants for near-infrared photodynamic therapy
The NIR absorbing photosensitizer phthalocyanine zinc (PC(Zn)) was stabilized in aqueous media as water-dispersible nanoparticles with a reduction- and pH-responsive full polysaccharide block copolymer. A cellular uptake and also photo switchable intracellular activity of the cargo upon irradiation at wavelengths in the near infrared region were shown. The block copolymer was synthesized by applying a copper-free click strategy based on a thiol exchange reaction, creating an amphiphilic double-stimuli-responsive mixed disulfide. The dual-sensitive polysaccharide micelles represent a non-toxic and biodegradable green macrosurfactant for the delivery of phthalocyanine zinc. By encapsulation i…
Amphiphilic Polysaccharide Block Copolymers for pH-Responsive Micellar Nanoparticles
A full polysaccharide amphiphilic block copolymer was prepared from end group-functionalized dextrans using copper-mediated azide-alkyne click chemistry. Sufficient modification of the reducing end in both blocks was achieved by microwave-enhanced reductive amination in a borate-buffer/methanol solvent system. The combination of a hydrophilic dextran block with a hydrophobic acetalated dextran block results in an amphiphilic structure that turns water-soluble upon acid treatment. The material has a low critical micelle concentration and self-assembles in water to spherical micellar nanoparticles. The formed nanoparticles have a narrow size distribution below 70 nm in diameter and disassembl…