title: Quantitative determination of carboxymethyl chitin in polymer-coated liposomes.
abstract: A simple turbidity method for the quantitative determination of carboxymethyl chitin (CM-chitin) in coated liposomes has been developed. Isopropanol:buffer (1:1 v/v) was selected as a good solvent system for dimyristoyl-, dipalmitoyl-, or egg phosphatidylcholines but not CM-chitin. The turbidity of CM-chitin in this solvent system was spectrophotometrically determined at 400 nm without significant interference by these phosphatidylcholines. The dependence of turbidity on the CM-chitin concentration, pH, and ionic strength were determined. It was found that analyses of the coating efficiency of dipalmitoylphosphatidylcholine liposomes by CM-chitin were reproducible within the specified ranges of formulation conditions and enabled differentiation of the effect of order of CM-chitin addition on the coating efficiency.
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Dong
authors.forename: J A
authors.initials: JA
authors.lastname: Rogers
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000032:analysis; D002686:Chitin / Q000031:analogs & derivatives* / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D008081:Liposomes / Q000032:analysis*; D009391:Nephelometry and Turbidimetry; D011108:Polymers / Q000737:chemistry; D012015:Reference Standards; D012997:Solvents
chemical_list: D008081:Liposomes; D011108:Polymers; D012997:Solvents; D002686:Chitin; D015060:1,2-Dipalmitoylphosphatidylcholine; C044872:O-(carboxymethyl)chitin