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	<title>Synthesis of Tosyl-Chitosan - Revision history</title>
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	<updated>2026-10-18T04:24:33Z</updated>
	<subtitle>Revision history for this page on the wiki</subtitle>
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	<entry>
		<id>https://eln.excellgen.com/index.php?title=Synthesis_of_Tosyl-Chitosan&amp;diff=12702&amp;oldid=prev</id>
		<title>Paul.xu: Created page with &quot;Chitin powder isolated from crab shells (Sigma, Lot. C7170) was&lt;br&gt;purified by stirring in a 5% NaOH aqueous solution for 3 days, recovered with&lt;br&gt;deionized water to pH 7 and dr...&quot;</title>
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		<updated>2014-08-01T22:43:17Z</updated>

		<summary type="html">&lt;p&gt;Created page with &amp;quot;Chitin powder isolated from crab shells (Sigma, Lot. C7170) was&amp;lt;br&amp;gt;purified by stirring in a 5% NaOH aqueous solution for 3 days, recovered with&amp;lt;br&amp;gt;deionized water to pH 7 and dr...&amp;quot;&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;Chitin powder isolated from crab shells (Sigma, Lot. C7170) was&amp;lt;br&amp;gt;purified by stirring in a 5% NaOH aqueous solution for 3 days, recovered with&amp;lt;br&amp;gt;deionized water to pH 7 and dried at 50 o C.&lt;br /&gt;
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&amp;lt;br&amp;gt;Preparation of chitin solution (1) and tosyl-chitin (2)&amp;lt;br&amp;gt;0.5g of Chitin (equiv. to 2.5 mmol of pyranose unit) and 1.3g of lithium chloride&amp;lt;br&amp;gt;(LiCl) dried respectively at 50 o C overnight and at 130 o C for 4h and cooled, and were&amp;lt;br&amp;gt;placed in a 100 ml three-necked flask fitted with rubber septa.&amp;lt;br&amp;gt;The flask was purged&amp;lt;br&amp;gt;with dry oxygen free nitrogen (OFN) and 26 ml of anhydrous DMAc was added via a&amp;lt;br&amp;gt;syringe.&amp;lt;br&amp;gt;The mixture was stirred at room temperature using a magnetic stirrer bar&amp;lt;br&amp;gt;until all solids were dissolved.&amp;lt;br&amp;gt;To the resultant chitin solution, was added Et 3 N (7.2&amp;lt;br&amp;gt;ml, 52mmol) followed by a solution of tosyl chloride (9.53g, 50mmol) in 12 ml&amp;lt;br&amp;gt;DMAc.&amp;lt;br&amp;gt;The reaction flask was transferred to the cold incubator and the reaction was&amp;lt;br&amp;gt;allowed to proceed at 8 o C for 24h at stirring speed of 250 rpm.&amp;lt;br&amp;gt;At the end of the&amp;lt;br&amp;gt;reaction, the mixture was filtered and the filtrate precipitated into 200 ml acetone,&amp;lt;br&amp;gt;washed with 300 ml methanol (100 ml × 3), 100 ml water (25 ml × 4) and 100ml&amp;lt;br&amp;gt;acetone.&amp;lt;br&amp;gt;The resulting product was freeze-dried to give 0.65g white color solid of&amp;lt;br&amp;gt;tosyl-chitin. The yield was 86.6%.&amp;lt;br&amp;gt;&amp;lt;br&amp;gt;&lt;br /&gt;
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[[Category:Paul]][[Category:Transfection]]&lt;/div&gt;</summary>
		<author><name>Paul.xu</name></author>
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