Extraction.ppt

Extraction refers to processes for the isolation of the active ingredients from drug material. This may be by physical means or by dissolving in a suitable menstruum (liquid solvent eg. water or alcohol). Expression is the physical act of applying pressure to squeeze out oils or juices from plants.

1. Extraction
SANJAY S. PATEL
Professor –Pharmaceutics Department
BMCPER, Modasa.
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2. Topics
•Definition
•Terminology
•Type of extraction
•Theory of extraction
•Solvent use in extraction
•Method of extraction
•Factor affecting choice of extraction process
•Application of extraction in pharmacy
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3. Definition
•Extractioncanbedefinedastheremovalof
solublematerialfromaninsolubleresidue,
eitherliquidorsolid,bytreatmentwitha
liquidsolvent.
•Thisismasstransferphenomena.
•Rateofextractionisnormallytherateof
diffusionofthesolutethroughtheliquid
boundary.
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4. Terminology
•Menstruum:solventusedforextractionpurpose
isknowasmenstruum
•Marc:Residualleftafterextractingthedesired
constituentsisknowasmarc.
•Macerate:Itisthesolutionofsoluble
constituentofdruginamenstruum.
•Galenicals:Thecruddrugextractisimpure.It
includeinfusion,decoctions,etcusedfororalor
externaluseknownasgalenical.
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5. Type of extraction
•Two types of extraction
1.Liquid –Liquid Extraction
2.Solid –Liquid extraction
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6. Liquid –Liquid Extraction
•Contactwithtwoimmisciblesolvent.
•Aconc.gradientissetupbetweenthephaseand
masstransferwilloccuruntilanequilibriumis
achieve.
•Highermasstransferrequirelargesurfacearea
forcontact,sufficienttimemustbeallowedin
thedispersedphasetoequilibriumandfinallythe
liquidareseparated.
•Inlargescaleequipmentrequirestirredintank.
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7. Solid –Liquid extraction
•Theextractionofsolublesubstancefrom
solidbymeanofasolventiscommonly
referredtoasleaching.
•Variousfactoraffectingtoremovalof
solublesubstanceininsolublematerial.
•Solidliquidextractionisimportantfor
medicinalplantmaterialwhichisgood
pharmacologicalactivity.
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8. Theory of extraction
1.Suitable size reduction of the drug:
2.Penetration of the solvent into the drug:
3.Solution of constituent:
4.Escape of the solution from the cells:
5.Separation of solution and exhausted drug:
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9. Suitable size reduction of the drug
Masstransfertheory-maximumsurfacearea
Toseparateindividualcellindrug–butitisnot
possible.
Prolongsizereduction–decompositionofconstituent
(volatileoil).
Degreeofsizereductiondependonbotanicalstructure
ofdrug.
Example-belladonnamoderatecoarsepowdercontain
higheralkaloidsthanfinepowder.
Thecellofdrugtobebrokenitexistpenetrationof
solventandescapeofsolublematter.
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10. Penetration of the solvent into the drug
Drugindrystateisporousduetoshrinkageandpores
containmustbedisplacedasthesolvententersinto
theporesandpenetrateintothecell.
Infreshmaterialcontainwaterfilmwhendriedshrinkage
occur.
Whendriedmaterialmoistenedreverseoccur,micellae
takeupaliquidoncemoreandtissueswell.
Insolventcontainhigherhydroxylgroupthanhigher
swellingisoccur.
Swellingcontinuesuntilthepressurecausedbytheliquid
layerisequaltothecohesiveforcebetweenmicellae.
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11. Solution of constituent:
•Solventpenetrateintocellandformation
ofsolutionofconstituenttakeplace.
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12. Escape of the solution from the cells
Brokencellescapeofsolutionisnotempeded.
Unbrokencellsolutionescapedependondiffusion
mechanism.
Rateofdiffusionwilldependupononpresenceof
suitableconcentrationgradient,boundarylayer
thickness,diffusioncoefficientofsoluteinsolvent.
1.Agitation
2.Solventflowrate.
3.Temperate.
Increasetemp.decreaseViscosityreduceboundarylayer.
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13. Separation of solution and exhausted drug
Immersiondruginbulksolvent.
Drugabsorbbysolventanddrugissubjected
topressuretoexpelasmuchassolution
possible.
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14. Solvent use in extraction
•Therearelargenumberofsolventusefor
extractionofdrugs.
•Theidealsolventshouldbeselectiveindissolving
onlythewantedconstitutes.
•Idealqualityofsolvent
•Cheap,Nontoxic
•Stable,Selective
•Plentiful,Lowviscosity
•Lowspecificheat
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15. I. Water as solvent
•Waterissolventforproteins,coloringmatter,
gum,sugars,enzymes,glycosides,tannins,
alkaloidssaltsetc.
•Waterisnotsolventforwaxes,fats,fixedoils,
alkaloids.
•Advantages:cheap,widesolventaction,non
toxic,noninflammable.
•Disadvantages:Nonselective,leadsto
hydrolysis,bacterialgrowinaq.Medium,
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16. II. Alcohol (Ethanol)
•Alcoholissolventforglycosides,tannins,
alkaloidssalts,Resins,volatileoilsetc.
•AlcoholisnotsolventforAlbumin,waxes,fats,
fixedoils,sucroseetc.
•Advantages:nontoxic,misciblewithwater,
bacterialcannotgrow,higherabsorptionofdrug
etc.
•Disadvantages:costly,hardensthetissuesand
thereforedelaysextraction
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17. III. Water alcohol mixture
IV. Acidifier water
V. Alkalized water
VI. Organic solvent: chloroform, ether,
benzene, etc.
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18. Method of extraction
I.Infusion
II.Decoction
III.Digestion
IV.Maceration
V.Percolation
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19. Infusion
•Vegetable drug containing water soluble & easily extractable
principle.
Drug + water (50ml + 50ml)
Stand for 15 min.
Add 900ml hot water.
Macerate during 30 min.
Separate solvent to marc.
•Use within 12 hrs because microbial attack is there.
•Examples: Infusion of senna
–Infusion of quassia
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20. Decoction
•Vegetable drug containing water soluble & heat stable
constitutes.
Drug + water (50ml + 1000ml)
Boil it for 15 min.
Cool it and liquid strained the marc passed.
•Use within 12 hrs because microbial attack is there.
•Examples: Decoction of irish moss BPC
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21. Digestion
•Itismodificationofmacerationanddrug
menstruummixtureiskepthot,between40to
60
o
C.
•inthismethodvolatilemenstruumisused,the
vesselisconnectedtoarefluxcondenser.
•Astemp.islowerthanthatusedforinfusionand
decoction,alongertimeisrequiredfor
extraction
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22. Maceration
•Maceration method based on the
immersion of drug in a bulk of solvent,
with modification to multiple stage
extraction.
•Three types :
1.Simple maceration
2.Modification maceration
3.Multiple maceration
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23. Simple maceration
•Process for organize drug (barks, root)
•Drug + whole of menstruum.
•Shake occasionally during 7 days.
•Strain of liquid and press the mark.
•Mix the liquid clarify.
•Filtrate is not adjusted to volume.
•Examples :
–Tincture of orange.
–Tincture of capsicum.
–Tincture of squill.
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24. Modification maceration
•Processforunorganizeddrug(gum,gum-resin)
•Drug+80%menstruum.
•Shakeoccasionallyduring2-7days.
•Decanttheliquidanddonotpressthemark.
•FiltertheliquidandpassmoreMestruumthroughmarcto
volumeandwashwithmarkwithfreshmenstruum(20%).
•Theconc.Andvolumeobtainissame,souponadjustingto
finalvolumedonotvarythestrengthfromworkertoworker.
•Examples:
–Tinctureofmyrrh.
–Tinctureoftolu.
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25. Multiple maceration
(multistage extractor.)
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26. Process:
1.Fillextractorwithdrug,addsolventandcirculaterunofftoreceiver1.
2.Fillextractorwithdrug,addsolventandcirculaterunofftoreceiver2.
3.Fillextractorwithdrug,addsolventandcirculaterunofftoreceiver3.
4.Removethedrugfromextractorandrecharge.Retunesolutionfrom1
toextractor.Evaporatesolvent.
5.Returnsolutionfrom2toextractorandcirculate.Runofftoreceiver
1.
6.Returnsolutionfrom3toextractorandcirculate.Runofftoreceiver
2.
7.Addfreshsolventtoextractorandcirculate.Runofftoreceiver3.
8.Removedrugfromextractorandrechange.Repeatcycle.
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27. Percolation
•Percolation is defined as short successive
maceration or extraction by the method of
displacement.
1.Simple percolation
2.Reserved percolation
3.Continuous hot percolation (soxhlet
extraction)
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28. Simple percolation
1.Size reduction
2.Imbibitions
3.Packing
4.Maceration
5.Percolation
6.Pressing the marc
7.Adjustment to volume
8.clarification
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29. Reserved percolation
•Itismodificationofsimplepercolation
•Drugpercolationrationis1:1or2:1.
Process:
Imbibefor4hoursmaceratefor24hrs.
Percolate
Reservedthe¾percolateoffinishedpreparationwhich
containmajoractiveconstitute.Themarcispressedand
mixedwithfurtherspecifiedvolumeofpercolate
separately.
Mixtheevaporatedpercolatewiththatreservedandadjust
tovolumewithmoremenstruum.
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30. Continuous hot percolation
(soxhlet extraction)
•It is modification of simple percolation
•It is used for those drug where:
–Penetration of Menstruum is slow in cellular
tissue.
–menstruum is vary less
–Active constitute are not readily soluble into
the menstruum.
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31. 31

32. Apparatus:
1.The flask holding menstruum.
2.The Extractor
3.The reflux condenser fitted top of the
soxhlet.
Process:
Advantages:
Disadvantages:
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33. Factor affecting choice of extraction process
•Nature of drug :
Hard and tough use percolation.
Soft, parenchymatous and unorganized, use maceration
method.
•Cost of drug
•Therapeutically value of drug
•Stability of drug : Drug is Thermostable.
•Time taken for drug
•Whether drug to be extracted completely or not
•solvent
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34. Application of extraction in
pharmacy
•Extraction is applicable for various analytical
method. (SCF, HPLC, GC, HPTLC. TLC)
•Extraction is use for various preparation.
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