title: Interfacial indazolization: novel chemical evidence for remarkably high exo-surface pH of cationic liposomes used in gene transfection.
abstract: Cationic liposomes are used as the carriers of polyanionic genes for combating against hereditary diseases in gene therapy. Studies directed to careful biophysical characterizations of the cationic liposomes commonly used in gene delivery have just begun. Herein, we report on a novel liposomal exo-surface bound indazolization reaction of an amphiphilic arenediazonium salt as evidence for the existence of remarkably alkaline exo-surface of cationic liposomes commonly used in gene transfection. Our results demonstrate that formation of 5-hexadecyl-7-methylindazole in thermal indazolization of 2,6-dimethyl-4-hexadecylbenzenediazonium tetrafluoroborate bound to liposome surface is a strong indication for the existence of significantly high exo-surface pH for cationic liposomes commonly used in gene delivery. The present method can be used in determining the relative exo-surface basicities of various cationic liposomes used in gene transfection and subsequently to find any possible correlation between the transfection efficiencies of these liposomes and their exo-surface basicities.
authors.affiliation: Division of Lipid Science and Technology, Indian Institute of Chemical Technology, Hyderabad 500 007, India.
authors.forename: R
authors.initials: R
authors.lastname: Banerjee
authors.forename: P K
authors.initials: PK
authors.lastname: Das
authors.forename: A
authors.initials: A
authors.lastname: Chaudhuri
mesh_terms: D001391:Azo Compounds / Q000737:chemistry; D002412:Cations / Q000737:chemistry; D002593:Cetrimonium Compounds / Q000737:chemistry; D004075:Diglycerides / Q000138:chemical synthesis; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods; D006863:Hydrogen-Ion Concentration; D007191:Indazoles / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry*; D015394:Molecular Structure; D000644:Quaternary Ammonium Compounds / Q000138:chemical synthesis; D014162:Transfection / Q000379:methods*
chemical_list: D001391:Azo Compounds; D002412:Cations; D002593:Cetrimonium Compounds; D004075:Diglycerides; D007191:Indazoles; D008081:Liposomes; D000644:Quaternary Ammonium Compounds; C054005:N-(1-(2,3-dioleyloxy)propyl)-N,N,N-trimethylammonium