Presumptive Drug TestsScreening for drugs orWhat could that white powder be?Retrieved from: http://www.whrhs.org/site/handlers/filedownload.ashx?moduleinstanceid=1289&dataid=1245&FileName=Presumptive_Drug_Tests.ppt

Presumptive TestsProsQuick, inexpensive, on the sceneCan be used for elimination purposesConsCannot be used in courtDo not definitively identify a drugDo not quantify amount

Controlled Substance AnalysisUnknown SubstancePlant?ConfirmationTestsMicro CrystalGC/MSIRMicroscopic ExaminationMacroscopicExaminationScreening TestsChemical ColorMicro CrystalTLCGC/FIDUV/VisChemical ExamDuquenoisTLCGC/FIDGC/MSNoYesYesYesYes

MarijuanaCannabis sativaMacroscopic TestsPalmate leaf with serrated edgesFluted stemsRed thread in budMicroscopic TestsBear claw shaped hairs on top surface of leafSmall crystals at base of leafhttp://www.dps.state.ia.us/DCI/Crime_Lab/Controlled_Substance/marij.shtml

HashishResin from marijuana that has been isolatedCake is smokedOil is added to other substances and smokedContains concentrated cannabinoidshttp://www.dea.gov/photos/hash/hash2.jpg

Duquesnois-Levine TestTest for presence of cannabinols, the active agent in marijuanaDuquenois agent is 2% vanillin, 1% acetaldehyde in ethanolPurple color denotes a positive testhttp://www.dea.gov/photo_library4.html

Thin Layer ChromatographyEstablishes the presence of specific cannabinoidsProvides a color testPositive if patterns match those of a known reference run at the same time

http://www.dps.state.ia.us/DCI/Crime_Lab/Controlled_Substance/add_tests.shtml

Proving Its PotThree tests must be positive!Microscopic botanical characteristics present?Positive Duquenois Levine Test?Positive TLC?

PeyoteMacroscopicButtons 1 in diameter5-10 orange like segmentsWhite tuft in each segmentChemical TestChromatography to identify characteristic pattern of alkaloidsMescaline is active ingredient

Magic MushroomsPsilocybe cubensis Off white stems with blue-gray stainingOff white to tan capsActive ingredientspsilocin psilocybin

Magic MushroomsCharacteristic UV spectraSeparate Using TLC then use UV light to image spotsColor TestsPurple with pDMBA (Van Urks)Red with fast blue B that then turns blue when HCl is added

Magic MushroomsPossession of mushrooms is not illegalProof of presence of psilocin or psilocybin is necessary to convictPsilocybin is fragile and easily converts to psilocin, so you have to prove the psilocin was there initially

psilocybinpsilocinseratonin(neurotransmitter)

Magic MushroomsPsilocybin will break down during gas chromatographyPre-react molecule to stabilize itUse Mass Spectroscopy to identify the reaction productChemical extraction with methanol prior to IR can break it downCant separate psilocin from psilocybin

Chemical Color TestsUse reagents that produce specific colors when reacting with certain classes of compoundsTarget the functional groupsPhenolsAromatic ringsPrimary, secondary and tertiary aminesChemically adding an auxochrome to drug molecule that shifts the optical absorption into the visible

Chemical Color TestsDetection limits of 1 to 50 gCan be used as developers for TLC plates

Chemical Color TestsNeed positive and negative controls to ensure reagents are reliableColors are influenced byExaminers subjectivityConcentrationDiluentsAdulterantsAge of reagentLength of time reaction is observed

Color TestsMethamphetamine/Marquis Reagent2% formaldehyde inSulfuric acidMethamphetamine/Sodium NitroprussideHeroin/Marquis ReagentHeroin/Mecke Reagenthttp://www.dps.state.ia.us/DCI/Crime_Lab/Controlled_Substance/cct.shtml#photo8

Color Test KitsAdd suspected substance to the pouch.SealBreak ampoules in orderCheck for color changehttp://www.crime-scene.com/ecpi/A-800-60XX.shtmlhttp://shop.armorforensics.com/mm5/merchant.mvc?Screen=PROD&Store_Code=Redwop&Product_Code=7624&Category_Code=narcotest

Color Test SequencesMayers Narcotics orAmphetaminesWhite precipBarbituatesNo precipMarquisDillye-KoppanyiOpiatespurpleAmphetaminesOrange to red tobrownDemerolbrownMescalineredEcstasyblackNitric AcidHeroinyellowMorphineRed to orange to yellowBarbituatesblueMandelins AmphetaminesOlive green confirmsMethadoneDark bluehttp://www.bvda.com/EN/prdctinf/pf_en_np.html16 different tests areavailable

Microcrystal TestsSample is dissolved in solutionReagent is added generating a precipitatePrecipitate has uniquely shaped crystalsMust have a reference standard using same reagentPotential problemsImpurities can distort crystal shapesHigh concentration leads to small crystalsReagent age effects

GHB date-rape drugCrystals following addition Of silver nitratehttp://www.lincoln.ac.uk/fabs/Research/Date%20rape%20research.htm

Microcrystalline Testshttp://www.dps.state.ia.us/DCI/Crime_Lab/images/blue42.jpgCocaineMethamphetamine

Thin Layer ChromatographyThe trick is getting the compounds out of the solid sample and on the plateChemical ExtractionsPhysical extractionDry wash and dry extractionLiquid/liquid extractions

Types of DrugsBasic drugs have an acid (HCl, etc.) as part of their salt formAcidic drugs have a base (Na, K) as part of their salt formNeutral drugs dont have an associated salt form

Solubility Guidelines

Acidic DrugsBasic DrugsNeutral DrugsAcidic Water SolutionsInsolubleSolubleSolubleBasic Water SolutionsSolubleInsolubleSolubleNeutral Water SolutionsFree acid is InsolubleFree base is InsolubleSolubleOrganicsFree acid is SolubleFree base is SolubleSoluble

Liquid/Liquid ExtractionDissolve in acidic aqueous solutionBasic drugs dissolveAdd organic solvent and shake Acid and neutral drugs go into organicRemove organic solvent after separationMake aqueous solution basicBasic drugs become insolubleAdd second organic and agitateBasic drugs dissolve in organicSeparate solventsUse organic fraction for IR or GC/MS