A new pH-responsive and glutathione-reactive, endosomal membrane-disruptive polymeric carrier for intracellular delivery of biomolecular drugs

• Published in: Journal of controlled release 2003-12, Vol.93 (2), p.105-120
• Main Authors: Bulmus, Volga, Woodward, Monica, Lin, Lianne, Murthy, Niren, Stayton, Patrick, Hoffman, Allan
• Format: Article
• Language: English
• Subjects: 3T3 Cells; Acrylates - adverse effects; Acrylates - chemical synthesis; Acrylates - metabolism; Acrylates - pharmacokinetics; Animals; Biological and medical sciences; Carbon Radioisotopes; Cell Survival - drug effects; Cytoplasmic delivery; Disulfides - adverse effects; Disulfides - chemical synthesis; Drug Carriers - adverse effects; Drug Carriers - chemistry; Drug Carriers - pharmacokinetics; Drug Delivery Systems - methods; Endosomal membrane disruption; Endosomes - drug effects; Erythrocytes - drug effects; Fluorescein-5-isothiocyanate - chemistry; General pharmacology; Glutathione; Glutathione - chemistry; Glutathione - metabolism; Glutathione - pharmacology; Hemolysis; Humans; Hydrogen-Ion Concentration; Intracellular Membranes - drug effects; Intracellular Space - drug effects; Intracellular Space - metabolism; Macrophages - drug effects; Macrophages - metabolism; Medical sciences; Methacrylates - chemical synthesis; Methacrylates - metabolism; Methacrylates - pharmacokinetics; Mice; Oligonucleotides, Antisense - metabolism; Oligopeptides - metabolism; Peptides - administration & dosage; Peptides - chemical synthesis; Peptides - pharmacokinetics; pH-sensitive polymer; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Polymer conjugates; Polymers - adverse effects; Polymers - chemical synthesis; Polymers - pharmacokinetics; Sulfhydryl Compounds - administration & dosage; Sulfhydryl Compounds - chemical synthesis; Sulfhydryl Compounds - pharmacokinetics
• ISSN: 0168-3659; 1873-4995
• DOI: 10.1016/j.jconrel.2003.06.001

In this study, we have designed, synthesized and characterized a novel pH-responsive polymeric carrier for the enhanced cytoplasmic delivery of enzyme susceptible drugs, such as antisense oligonucleotides, proteins and peptides. A novel functionalized monomer, pyridyl disulfide acrylate, was synthesized and incorporated into an amphiphilic copolymer consisting of methacrylic acid and butyl acrylate, which resulted in a glutathione- and pH-sensitive, membrane-disruptive terpolymer with functional groups, that allow thiol-containing molecules to be readily conjugated. Conjugation and/or ionic complexation with oligopeptides or antisense oligonucleotides were performed and characterized. Hemolytic activity at low pHs remained high even after the conjugation/complexation with oligopeptides and asODNs. This polymer showed no toxicity, as determined with mouse 3T3 fibroblasts and human THP-1 macrophage-like cells. Uptake of the radiolabeled polymer and enhanced cytoplasmic delivery of FITC-ODN was also studied in THP-1 macrophage-like cells.