title: Polymeric phosphorylcholine-camptothecin conjugates prepared by controlled free radical polymerization and click chemistry.
abstract: Novel polymer-drug conjugates, consisting of zwitterionic poly(methacryloyloxyethyl phosphorylcholine) (polyMPC) as the polymer component, and camptothecin (CPT) as the drug, were prepared by two methods. In one case, CPT was transformed by acylation into a functional initiator for copper catalyzed atom transfer radical polymerization (ATRP), and polyMPC was grown from this therapeutic initiator. In the other case, a one-pot ATRP-"click" conjugation strategy was employed to synthesize novel polyMPC structures containing multiple copies of the drug pendant to the zwitterionic polymer chain. The latter method allows polyMPC-graft-CPT conjugates to be prepared with a high weight percent drug loading (up to 14% CPT) with excellent solubility in pure water (>250 mg/mL). The linkage chemistry chosen between the polyMPC backbone and the pendant drugs proved critically important for assuring drug release within a time frame reasonable to consider these structures as a platform for injectable cancer therapeutics. Liberation of the drug from the polymer backbone was monitored by high-performance liquid chromatography, using size-exclusion and reverse-phase columns, and the toxicity of the polymer-drug conjugates was examined in cell culture against breast (MCF7), ovarian (OVCAR-3), and colorectal (COLO 205) cancer cell lines.
authors.affiliation: Polymer Science & Engineering Department, 120 Governors Drive, University of Massachusetts, Amherst, Massachusetts 01003, USA.
authors.forename: Xiangji
authors.initials: X
authors.lastname: Chen
authors.forename: Samantha
authors.initials: S
authors.lastname: McRae
authors.forename: Sangram
authors.initials: S
authors.lastname: Parelkar
authors.forename: Todd
authors.initials: T
authors.lastname: Emrick
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D002166:Camptothecin / Q000737:chemistry* / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003432:Cross-Linking Reagents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D005609:Free Radicals / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D008689:Methacrylates / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D015394:Molecular Structure; D010316:Particle Size; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D011109:Polymethacrylic Acids; D012995:Solubility; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D003432:Cross-Linking Reagents; D005609:Free Radicals; D008689:Methacrylates; D011109:Polymethacrylic Acids; C115766:poly(2-methacryloyloxyethyl-phosphorylcholine); D010767:Phosphorylcholine; D002166:Camptothecin