第二章 药物溶液的配制理论-2013VIP免费

药学院药剂学教研室2学习要求（learningobjectives）•Identifytheconceptofsolution，saturatedsolution，unsaturatedsolution，supersaturatedsolution(掌握溶液、饱和溶液、不饱和溶液、超饱和溶液的概念)•掌握药物溶解度与溶出速度的概念与表示方法，影响药物溶解度与溶出速度的因素及增加药物溶解度与溶出速度的方法。•熟悉药用溶剂的种类及性质；溶解度的测定方法；理解药物在油水两相中分配的含义。3药物溶液的形成—基本理论知识4SomeDefinitions5PartsofaSolutionSOLUTE(溶质)–thepartofasolutionthatisbeingdissolved(usuallythelesseramount)SOLVENT（溶剂）–thepartofasolutionthatdissolvesthesolute(usuallythegreateramount)Solute+Solvent=Solution（溶液）6DefinitionsSolutionscanbeclassifiedassaturatedorunsaturated（不饱和的）.Asaturatedsolutioncontainsthemaximumquantityofsolutethatdissolvesatthattemperature.Anunsaturatedsolutioncontainslessthanthemaximumamountofsolutethatcandissolveataparticulartemperature7Definitions《中国药典》关于溶解度的描述方法《中国药典》关于溶解度的描述方法solubilitysolubility（溶解度）（溶解度）：在一定温度一定温度下，在一定量溶剂一定量溶剂中达饱和时饱和时溶解的最大药量。是反映药物溶解性的重要指标。solubilitysolubility（溶解度）（溶解度）：在一定温度一定温度下，在一定量溶剂一定量溶剂中达饱和时饱和时溶解的最大药量。是反映药物溶解性的重要指标。溶解度术语溶解限度极易溶解易溶溶解略溶微溶极微溶几乎不溶或不溶系指溶质1g（ml）能在溶剂不到1ml中溶解系指溶质1g（ml）能在溶剂1~不到10ml中溶解系指溶质1g（ml）能在溶剂10~不到30ml中溶解系指溶质1g（ml）能在溶剂30~不到100ml中溶解系指溶质1g（ml）能在溶剂100~不到1000ml中溶解系指溶质1g（ml）能在溶剂1000~不到10000ml中溶解系指溶质1g（ml）在溶剂10000ml中不能完全溶解8DefinitionsSUPERSATURATEDSOLUTIONScontainmoresolutethanispossibletobedissolved一定温度、压力下，当溶液中溶质的浓度已超过该温度、压力下的溶质的溶解度，而溶质仍不析出的现象叫过饱和现象，此时的溶液称为过饱和溶液9Supersaturatedsolutionsareunstable.Thesupersaturationisonlytemporary,andusuallyaccomplishedinoneoftwoways:1.Warmthesolventsothatitwilldissolvemore,thencoolthesolution2.Evaporatesomeofthesolventcarefullysothatthesolutedoesnotsolidifyandcomeoutofsolution过饱和溶液是不稳定的，当往溶液中加入一小块溶质晶体，即能引起过饱和溶液中溶质的结晶。10SupersaturatedSodiumAcetate(醋酸钠)Oneapplicationofasupersaturatedsolutionisthesodiumacetate“heatpack.”11醋酸钠溶解和结晶的反应式为：当醋酸钠过饱和溶液结晶时，反应向左边进行，放出大量的热结晶后的溶液可以重新加热使用，循环利用12IONICCOMPOUNDSCompoundsinAqueousSolutionManyreactionsinvolveioniccompounds,especiallyreactionsinwater—aqueoussolutions.13AqueousSolutionHowdoweknowionsarepresentinaqueoussolutions?Thesolutions_______________TheyarecalledELECTROLYTESHCl,MgCl2,andNaClarestrongelectrolytes.Theydissociatecompletely(ornearlyso)intoions.14AqueousSolutionsSomecompoundsdissolveinwaterbutdonotconductelectricity.Theyarecallednonelectrolytes.Examplesinclude:sugarethanolethyleneglycol(乙二醇)1516摩尔浓度/物质的量浓度由于溶液的体积随温度而变，物质的量浓度也随温度而变。171.0Lofwaterwasusedtomake1.0Lofsolution.Noticethewaterleftover.18PROBLEM:Dissolve5.00gofNiCl2•6H2Oinenoughwatertomake250mLofsolution.CalculatetheMolarity.Step1:calculatemolesofNiCl2•6H2OStep2:calculatemolarity[NiCl2•6H2O]=0.0841M19USINGMOLARITYWhatmassofoxalicacid,H2C2O4,isrequiredtomake250.mLofa0.0500Msolution?Moles=M·VStep1:ChangemLtoL.250mL*1L/1000mL=0.250LStep2:Calculate.Moles=(0.0500mo...