title: [Studies on design, synthesis and biodegradation of carrier for colon-site specific, drug delivery system].
abstract: OBJECTIVE
  To design and synthesize a novel vector for colon-site specific drug delivery system and investigate the relationship between the biodegradation properties and composition of materials in the simulated colon fluid.
  
  
  METHODS
  The azocopolymer P (HEMA-MMA-MAA) was synthesized using 2-hydroxyethylmethacrylate (HEMA), methyl methacrylate (MMA) and methacrylic acid (MAA) as comonmer, azobisisobutyronitrilel (AIBN) as initiator, cross-linked with divinylazobezene (DVAB). The chemical structure of the synthesized series of azocopolymer is examined by UV, FTIR spectroscopy and nuclear magnetic resonance data. Their swelling behavior is evaluated by the swelling equilibrium parameter Q, the biodegradation tests of the materials were carried out at physiologically relevant buffer designed to mimic the colon environment. The biodegradation properties were assessed using the differential scanning calorimeters (DSC) and gel permeation chromatography (GPC) and the morphology on the surface of materials before and after degradation was observed by scanning electron microscopy (SEM).
  
  
  RESULTS
  The swelling equilibrium parameter Q increased with increasing the contents of HEMA and MAA in the materials. The degradation behavior was relevant to the ratio of three components in the copolymers.
  
  
  CONCLUSIONS
  This materials may become a good carrier for the colon-site specific drug delivery system if the contents of commoners HEMA, MMA and MAA are adjusted reasonably.
authors.affiliation: Department of Pharmaceutical Science, Nanfang Hospital, First Medical University of PIA, Guangzhou 510S15, China. jhchen@fimmu.com
authors.forename: Jian-hai
authors.initials: JH
authors.lastname: Chen
authors.forename: Qing-yuan
authors.initials: QY
authors.lastname: Chen
authors.forename: Jia-rui
authors.initials: JR
authors.lastname: Sheng
authors.forename: Qi-zhi
authors.initials: QZ
authors.lastname: Luo
mesh_terms: D001391:Azo Compounds / Q000008:administration & dosage* / Q000378:metabolism; D001673:Biodegradation, Environmental; D003106:Colon / Q000378:metabolism*; D004337:Drug Carriers / Q000138:chemical synthesis / Q000378:metabolism; D016503:Drug Delivery Systems; D005243:Feces / Q000382:microbiology; D006801:Humans; D008689:Methacrylates; D020366:Methylmethacrylate; D011108:Polymers / Q000008:administration & dosage / Q000378:metabolism; D013678:Technology, Pharmaceutical / Q000379:methods
chemical_list: D001391:Azo Compounds; D004337:Drug Carriers; D008689:Methacrylates; D011108:Polymers; D020366:Methylmethacrylate; C008384:methacrylic acid; C005044:hydroxyethyl methacrylate