کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9901447 1545421 2005 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Molecular weights of poly(butyl cyanoacrylate) nanoparticles determined by mass spectrometry and size exclusion chromatography
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی بیوتکنولوژی یا زیست‌فناوری
پیش نمایش صفحه اول مقاله
Molecular weights of poly(butyl cyanoacrylate) nanoparticles determined by mass spectrometry and size exclusion chromatography
چکیده انگلیسی
Matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and size exclusion chromatography (SEC) were employed to elucidate the chemical composition, mean number average molecular weight (Mn), mean weight average molecular weight (Mw), and polydispersity (PD) of poly(butyl cyanoacrylate) (PBCA) manufactured by emulsion polymerisation. Both methods gave similar results for Mn, but substantial differences were observed for Mw and PD, with MALDI producing consistently lower values which could not be improved by off-line coupling of SEC and MALDI. MALDI gave a more detailed view on the chemical composition of the cyanoacrylate and revealed the presence of two additional polymer series with different end groups besides the expected PBCA series, which showed different retention in SEC. Their formation is explained by the secession/addition of formaldehyde from/to the regular polymer via (reverse) Knoevenagel reaction. In additional experiments, the influence of different pH on PBCA-NP during polymerisation was examined by comparison of polymerisation yield and particle diameter to their chemical composition as revealed by the MALDI spectra. The most uniform nanoparticles, with the highest polymerisation yield, narrowest particle size, and mass distribution were produced at pH 1.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: European Journal of Pharmaceutics and Biopharmaceutics - Volume 60, Issue 3, August 2005, Pages 391-399
نویسندگان
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