ASTM_E_2125_-_11.pdf

Designation:E212511Standard Guide forMicrocrystal Testing in Forensic Analysis of Phencyclidineand Its Analogues1This standard is issued under the fixed designation E2125;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.INTRODUCTIONMicrocrystal tests are primarily chemical-precipitation tests in which a light microscope is used toobserve and distinguish the different types of crystals formed.These tests require skill and expertiseon the part of the analyst that can be adequately gained only through appropriate training andexperience in their use.These tests should not be attempted by those who are unfamiliar with themfor use in the analysis of phencyclidine and its analogues.1.Scope1.1 This guide describes some standard procedures appli-cable to the analysis of phencyclidine and its analogues usingmicrocrystal tests(1-8).21.2 These procedures are applicable to phencyclidme and itsanalogues which are present in solid dosage form or in a liquidform.They are not typically applicable to the analysis ofphencyclidine and its analogues in biological samples.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 This standard cannot replace knowledge,skill,or abilityacquired through appropriate education,training,and experi-ence and should be used in conjunction with sound profes-sional judgment.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3E1459 Guide for Physical Evidence Labeling and RelatedDocumentationE1492 Practice for Receiving,Documenting,Storing,andRetrieving Evidence in a Forensic Science LaboratoryE1732 Terminology Relating to Forensic ScienceE2329 Practice for Identification of Seized DrugsE2548 Guide for Sampling Seized Drugs for Qualitative andQuantitative Analysis3.Terminology3.1 For definitions of terms used in this standard,refer toTerminology E1732.3.2 Definitions:3.2.1 aggregationthe collecting of units or parts into amass or whole.3.2.2 birefringenceproperty of some crystals having morethan one refractive index;this will result in interference colorswhich are viewed through a polarized light microscope.3.2.3 grainsthick tablets having nearly equal width,breadth,and thickness.3.2.4 habitthe external morphology of the crystal.3.2.5 microdropa small drop of liquid that would fit on theend of a standard size,flattened toothpick;the approximatevolume of this drop would be 10 to 25 L.3.2.6 nailsa skeleton of some kinds of triangles,elon-gated,usually pointed with a short head usually thicker orbroader.3.2.7 needles(acicular)long,thin crystals with pointedends.3.2.8 nuggetsirregularly formed grains without sharpfaces or edges.1This guide is under the jurisdiction of ASTM Committee E30 on ForensicSciences and is the direct responsibility of Subcommittee E30.01 on Criminalistics.Current edition approved March 1,2011.Published April 2011.Originallyapproved in 2001.Last previous edition approved in 2007 as E2125 07.DOI:10.1520/E2125-11.2The boldface numbers in parentheses refer to a list of references at the end ofthis standard.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.9 plierscrystalsresemblingpliers,generallyX-shaped.3.2.10 razor bladesthin oblong crystals with length abouttwice the width,resembling a safety razor blade.3.2.11 sheaveselongated crystals form two opposite fansfrom the same joining point.3.2.12 skeletal crystala crystal in which all of the spacesin the crystal lattice are not occupied.3.2.13 spindlesshorter than course needles,but more sub-stantial cross-section.4.Summary of the Technique4.1 A small sample of the material containing the suspectedphencyclidine or its analogues is dissolved in a dilute acid andthe appropriate precipitating reagent is added.The crystals thatare formed are observed and distinguished utilizing a lightmicroscope.5.Significance and Use5.1 The technique produces a chemical-precipitation reac-tion between the phencyclidine or its analogues and theprecipitating reagent.The habit and the aggregation of thecrystals formed may be used to distinguish phencyclidine or itsanalogues from other drugs.5.2 The technique can be utilized on phencyclidine or itsanalogues present in either the salt