title: In vitro photo-controlled drug release system based on amphiphilic linear-dendritic diblock copolymers; self-assembly behavior and application as nanocarrier.
abstract: OBJECTIVE
  A simple type of photoresponsive amphiphilic linear-dendritic diblock copolymer has been synthesized and investigated for its ability to act as a drug carrier. These structures contain hydrophilic polyethylene oxide monomethyl ether (PEOM) as hydrophilic block and carbosiloxane dendritic branches as hydrophobic block grafted by two and six Magneson II as azo chromophore, PEOM-Azo, 2 and PEOM-Azo, 6 respectively. Self-assembling of the amphiphilic macromolecules of PEOM-Azo, 2 and PEOM-Azo, 6, briefly were represented as PEOM-Azo [2, 6], leads to the formation of their micellar aggregates in aqueous media.
  
  
  METHODS
  Their micellar properties such as critical micelle concentration (CMC), aggregation number and thereby total numbers of azo-groups in each micellar aggregates were determined. Also, they were characterized by TEM, SEM and DLS.
  
  
  RESULTS
  The unloaded aggregates examined under UV light (366 nm), which were observed to be smaller than 300 nm. The release patterns of the encapsulated drug molecule from these aggregates were investigated as regulated by the PEOM-Azo [2, 6] systems in trans and cis forms.
  
  
  CONCLUSIONS
  A comparison of the release behavior of the loaded PEOM-Azo [2, 6] systems indicated that the release rate of the encapsulated active molecules from the carriers was slower when the azo moieties were in trans form as compared to that the azo in the cis form. The in vitro release behavior of drug from these polymeric systems represents potential of the carriers for controlled drug delivery.
authors: Research Laboratory of Carbohydrates and Biopolymers, Faculty of Chemistry, University of Tabriz, Tabriz, Iran. namazi@tabrizu.ac.ir
authors: Hassan
authors: H
authors: Namazi
authors: Saeed
authors: S
authors: Jafarirad
mesh_terms: D001391:Azo Compounds / Q000737:chemistry; D001682:Biological Availability; D002850:Chromatography, Gel; D003692:Delayed-Action Preparations / Q000138:chemical synthesis / Q000737:chemistry; D004337:Drug Carriers / Q000138:chemical synthesis / Q000737:chemistry*; D000069347:Erlotinib Hydrochloride; D007536:Isomerism; D008027:Light; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D008854:Microscopy, Electron; D010316:Particle Size; D055668:Photochemical Processes; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry* / Q000528:radiation effects; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D011721:Pyrenes / Q000737:chemistry; D011799:Quinazolines / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D012542:Scattering, Radiation; D012833:Siloxanes / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013501:Surface-Active Agents / Q000138:chemical synthesis / Q000737:chemistry; D014466:Ultraviolet Rays
chemical_list: D001391:Azo Compounds; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D008823:Micelles; D011108:Polymers; D047428:Protein Kinase Inhibitors; D011721:Pyrenes; D011799:Quinazolines; D012833:Siloxanes; D013501:Surface-Active Agents; D011092:Polyethylene Glycols; C030984:pyrene; D000069347:Erlotinib Hydrochloride