User:Allison K. Alix/Notebook/CHEM-581/2013/02/06
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==Calculations== | ==Calculations== | ||
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| + | '''Preparation of 20mM phosphate buffer, pH = 7.4''' | ||
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| + | [Base] = monosodium phosphate, 119.98 g/mol | ||
| + | [Acid] = disodium phosphate, 141.96 g/mol | ||
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| + | pH = pKa + log ([Base]/[Acid]) | ||
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| + | 7.4 = 7.3 + log ([Base]/[Acid]) | ||
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| + | ([Base]/[Acid]) = 1.2589 | ||
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| + | [Acid] + [Base] = 20mM | ||
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| + | [Base] = 20mM - [Acid] | ||
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| + | (20mM - [Acid])/[Acid] = 1.2589 | ||
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| + | [disodium phosphate] = 8.85mM | ||
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| + | [monosodium phosphate] = 11.14mM | ||
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| + | 8.85mmol x 141.96g/mol x 1mol/1000mmol = 1.256g disodium phosphate | ||
==References== | ==References== | ||
Revision as of 10:35, 6 February 2013
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Objective-Begin PVA microsphere preparation ProcedurePreparation of 20mM phosphate buffer, pH = 7.4 [Base] = monosodium phosphate, 119.98 g/mol [Acid] = disodium phosphate, 141.96 g/mol pH = pKa + log ([Base]/[Acid]) 7.4 = 7.3 + log ([Base]/[Acid]) ([Base]/[Acid]) = 1.2589 [Acid] + [Base] = 20mM [Base] = 20mM - [Acid] (20mM - [Acid])/[Acid] = 1.2589 [disodium phosphate] = 8.85mM [monosodium phosphate] = 11.14mM 8.85mmol x 141.96g/mol x 1mol/1000mmol = 1.256g disodium phosphate 11.14mmol x 119.98g/mol x 1mol/1000mmol = 1.337g monosodium phosphate CalculationsPreparation of 20mM phosphate buffer, pH = 7.4 [Base] = monosodium phosphate, 119.98 g/mol [Acid] = disodium phosphate, 141.96 g/mol pH = pKa + log ([Base]/[Acid]) 7.4 = 7.3 + log ([Base]/[Acid]) ([Base]/[Acid]) = 1.2589 [Acid] + [Base] = 20mM [Base] = 20mM - [Acid] (20mM - [Acid])/[Acid] = 1.2589 [disodium phosphate] = 8.85mM [monosodium phosphate] = 11.14mM 8.85mmol x 141.96g/mol x 1mol/1000mmol = 1.256g disodium phosphate Referenceshttp://www.sciencedirect.com/science/article/pii/S0168365998000893
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