کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2505941 1557504 2007 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Analysis of Quil A–phospholipid mixtures using drift spectroscopy
موضوعات مرتبط
علوم پزشکی و سلامت داروسازی، سم شناسی و علوم دارویی علوم دارویی
پیش نمایش صفحه اول مقاله
Analysis of Quil A–phospholipid mixtures using drift spectroscopy
چکیده انگلیسی

The aim of this study was to investigate molecular interactions between Quil A and phosphatidylcholine in the solid state using diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS). Analysis of the interactions was characterized on the different regions of phosphatidylcholine: hydrophobic chain, interfacial and headgroup regions. The spectra of the hydrocarbon region of phosphatidylcholine alone compared to that for the binary mixture of Quil A and phosphatidylcholine were similar. These findings suggest that Quil A did not cause conformational disorder of the fatty acyl chains of the phospholipid. In contrast, a shift in the wavenumber of the choline group and a broad band in this moiety indicate a modification of the phospholipid in the headgroup region due to interaction between Quil A and phosphatidylcholine. These results suggest possibly ionic interactions between the negatively charged glucuronic acid moiety of the Quil A molecule with the positively charged choline group. The findings could also be the result of conformational changes in the choline group because of the intercalation of sugar moieties in Quil A between the choline and phosphate groups due to hydrogen bonding. Shift of wavenumbers to lower values on the carbonyl group was observed suggesting hydrogen bonding between Quil A and phosphatidylcholine. The difference in degrees of wavenumber shift (choline > phosphate > carbonyl group) and observed broad bands indicated that Quil A preferentially interacted with phosphatidylcholine on the hydrophilic headgroup. Cholesterol influenced such interactions at relatively high concentration (60%, w/w).

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Pharmaceutics - Volume 342, Issues 1–2, 5 September 2007, Pages 49–61
نویسندگان
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