https://eln.excellgen.com/index.php?action=history&feed=atom&title=N-acetylated_Chitosan 2026-10-18T05:46:23Z Revision history for this page on the wiki MediaWiki 1.44.0 https://eln.excellgen.com/index.php?title=N-acetylated_Chitosan&diff=12489&oldid=prev 2014-07-23T15:22:42Z

<p>Created page with &quot;&lt;br&gt; Chitosan 10B (0.6 g) was suspended&lt;br&gt;in distilled water (0.05 dm 3 ) and 20% aqueous acetic acid&lt;br&gt;(0.05 dm 3 ) was added gradually to the suspension with vig-&lt;br&gt;orous m...&quot;</p> <p><b>New page</b></p><div>&lt;br&gt;<br /> <br /> Chitosan 10B (0.6 g) was suspended&lt;br&gt;in distilled water (0.05 dm 3 ) and 20% aqueous acetic acid&lt;br&gt;(0.05 dm 3 ) was added gradually to the suspension with vig-&lt;br&gt;orous mixing. The suspension was mixed with magnetic&lt;br&gt;stirrer for over 1 day until it became a viscous, transpar-&lt;br&gt;ent and homogeneous solution. Subsequently, the required&lt;br&gt;amount of acetic anhydride (0.38–9.50 g) was poured gen-&lt;br&gt;tly into the solution with mixing at ambient temperature.&lt;br&gt;After stirring for 5 h, the reaction mixture was adjusted to&lt;br&gt;pH 9 with 5 mol dm −3 aqueous KOH solution and poured&lt;br&gt;into acetone (0.3 dm 3 ) in order to obtain the resulting NAC&lt;br&gt;as precipitate. The precipitate was filtered and suspended&lt;br&gt;in 1 mol dm −3 methanolic KOH solution. After stirring for&lt;br&gt;6 h, the resulting precipitate was filtered and rinsed with&lt;br&gt;methanol until the filtrate became neutral. Finally, the pre-&lt;br&gt;cipitate was lyophilized.&lt;br&gt;<br /> <br /> &lt;br&gt;<br /> <br /> &lt;br&gt;<br /> <br /> mixture of chitosan (5 g) and aqueous acetic&lt;br&gt;acid (600 ml, 0.12 M) was stirred for 24 h to ensure&lt;br&gt;total solubility. The pH was adjusted to 7.2 by slow&lt;br&gt;addition of 0.1 M NaOH with strong agitation,&lt;br&gt;yielding a gel slurry, the volume of which was&lt;br&gt;adjusted to about 900 ml. Palmitoyl chloride (20&lt;br&gt;ml,&lt;br&gt;d&lt;br&gt;=0.907 g/ml) was then added and the reaction&lt;br&gt;volume diluted to 1 l with distilled water. Similarly,&lt;br&gt;different volumes (10–60 ml) of palmitoyl chloride&lt;br&gt;were used to obtain various degrees of substitution.&lt;br&gt;Other derivatives were obtained using the same&lt;br&gt;conditions, substituting 20 ml of caproyl, octanoyl,&lt;br&gt;or myristoyl chloride. After 4–6 h, each preparation&lt;br&gt;was neutralized (pH 6.8–7.0) and precipitated with&lt;br&gt;acetone. The precipitate, collected by filtration, was&lt;br&gt;washed at 50–60 C with an excess of methanol and&lt;br&gt;decanted. The washing was repeated three times to&lt;br&gt;eliminate free fatty acids&lt;br&gt;<br /> <br /> <br /> <br /> <br /> <br /> [[Category:Paul]][[Category:Transfection]]</div>

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