Review Article VALIDATION OF ANALYTICAL METHODS - STRATEGIES & SINGFICANCE

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International Journal of Research and Development in Pharmacy and Life SciencesAvailable online at http//www.ijrdpl.comApril - May, 2015, Vol. 4, No.3, pp 1489-1497ISSN (P): 2393-932X, ISSN (E): 2278-0238Review ArticleVALIDATION OF ANALYTICAL METHODS – STRATEGIES & SINGFICANCEShashi daksh1*, Anju goyal1, Chakshu k. pandiya21. Department of quality assurance, B.N. Institute of pharmaceutiacl sciences, Udaipur, 313001.2. Reliance formulation pvt. Itd. 7/2-A GIDC estate, phase-1, vatva, Ahemdabad.*Corresponding Author: Email dakshshashi84@gmail.com(Received: January 18, 2015; Accepted: March 12, 2015)ABSTRACTThe development of sound Analytical method(s) is of supreme importance during the process of drug discovery, release to market and development,culminating in a marketing approval. The objective of this paper is to review the method development, optimize and validation of the method for the drug productfrom the developmental stage of the formulation to commercial batch of the product. Method development for the interested component in finished product or inprocess tests and the sample preparation of drug product and to provide practical approaches for determining selectivity, specificity, limit of detection, limit ofquantitation, linearity, range accuracy, precision, recovery solution stability, ruggedness, and robustness of liquid chromatographic methods to support the Routine, inprocess and stability analysis.Keywords: Analytical method development, validation parameters, acceptance criteria.INTRODUCTIONinThe reliability of an analytical finding is a matter of greatbatch and accelerated stability testing samples. It is alsoimportanceimportant to emphasize that each analytical technique has itstodrivetheformulation scientist in thethelaboratoriesdevelopmental stage and impurity profile in stability studyownand dissolution data of the stability study as well asanalyte. In these instances, specific validation criteria mayroutine analysis. Theisneed to be developed for each analyte. Moreover, theroutineappropriateness of the technique may also be influencedanal ysis and stability analysis. This is especially true in theby the ulti mate objective of the study. When samplecontext of quality management and accreditation, whichanalysis for a given study is conducted at more than one sitehave become matters of increasing importance in analyticaland commercialin dissolution andrecentnecessary to validate the analytical method(s) as per ICHyears. Therefore, this topic should extensively be discussedguidelines and to provide proper validation information foron an international level to reach an accord on the extentdifferent sites and different parameter and to establishof validation experiments and on acceptance criteria forinter and intra laboratory reliability2.validation parameters of anal ytical methods1.ANALYTICAL METHOD DEVELOPMENT AND VALIDATIONNEED OF ANALYTICAL METHOD VALIDATIONAnalytical method development is the process by which aIt is essential to employ well-characterized and fullyspecific analytical method is to be developed for drugvalidated anal ytical methods to yield reliableproducts from the stage of in process to finished product andimportanceofvalidationproducing reliable and repeatable results forimpurityprofile SRDE Group, All Rights Reserved.intheresultscharacteristics,while anal ysing the registrationwhichbatch forwillvaryfrom analyte topeople consumption, it isInt. J. Res. Dev. Pharm. L. Sci.1489

Daksh S. et. al., April - May, 2015, 4(3), 1489-1497minivalidation to be done before starting the analyses ofVALIDATION PARAMETERSroutine samples,Linearityinvestigationsamplesandstabilit ysamples. Analytical method development and finalizing theA linear relationship should establish across the range asmethod consists ofper table 3 given below. It may be demonstrated1. Standardizing the working standard from referencedirectly on the active substance by linear dilution andstandard.percentage level of each parameter gi ven below table 3.2. Optimizing the chromatographic condition, concentrationThe linear range of the method must be determinedof standard and sample solution and extraction procedure ofregardless of the all stage of the formulation duringthe sample.drug development. ICH guidelines recommend evaluating a3. Analyticaltominimum of five concentrations to assess linearity and wideranalysing (routine samples) tests likerange of concentration and other approaches should beassay, dissolution and related substance in developmentjustified. The correlation coefficient, Y-intercept, Slope of thelaboratories etc.regression line and residual sum of square shall be submitted4. Prior starting the validation the satisfactory result shouldby appropriate statistical method5.be found in mini validation and formulation should beThefinalized3.performing serial dilutions of a single stock solution, forVALIDATIONrelated substance, residual solvent impurity blend or solventIt is accepted that during the course of a typical drugblend shall be used. The response of the interested llverification or mini validationprogram,undergoadefined analyticalmany modifications on. heoreticalmethod relativecompositionchanges, lower strength may be added orresponse factors and relative retention times for eachpercentageof coating material may change on theimpurity should establish with respect to the activeformulation. Becauseanalyticalcompound. Response factors allow the end user to notmethod may be modified and if modified it should beusing the impurity material for each analysis, and it is usefulverified so it requires different levels of validation.to correcting for response differences and final impurityTwo different levels/types of method validations, completecalculation.validation and partial validation or mini, validation, arelinearity curve method or about 0.2 and 0.4 percent fordefined and characterized as follows.each impurity and the active compoundComplete validationinjected and find the relative response factor from theComplete validation is necessary before executing clinicalslope of the linearity curve or ratio between thebatch or registration batch of drug product. If anyresponse factor of impurity and response factor of activemodification in the formulation or if any impurity found in thecompound6.stabilitySelectivity tobe modifiedTodetermine the relative response factors,shouldbeand validated again, and the parameters are detailedFor clinical and before registration batch of the drugbelow for the complete validation given table 1.product, the analytical method must demonstrate specificityMini validationincluding degradation study. The method must have theMini validations is required for all the test methods likeability to separate each known impurity and degradationAssay, Related substance, UOD and Blend Uniformity forproduct at the Quantitation level and if any blank, placeboanalysing the routine samples prior starting the completepeaks are found it should be properly separated fromvalidation.impurity peak and interested peak.Some parameters to be checked as per ICH GuidelinesFor identification tests, discrimination of the method shoulddetailed below given table 2 and acceptance criteria discussbe demonstrated by obtaining positivelater4.samples containing the analyte and negative results for SRDE Group, All Rights Reserved.Int. J. Res. Dev. Pharm. L. Sci.resultsfor1490

Daksh S. et. al., April - May, 2015, 4(3), 1489-1497samples not containing the analyte. The method must bespectral evaluation of degradation product peak and eachable to differentiate between the analyte of interest andknown impurity peak should not show any significant changescompounds with a similar chemical structure that may bein the fragmentation pattern from the parent compound9.present. For a high performance liquid chromatographyPrecision(HPLC) identification test, peak purity evaluation should bePrecision reflects the closeness of agreement of a series ofused to assess the homogeneity of the peak corresponding tomeasurements between the series measurement obtainedthe analyte of interest7.from multiple sampling from the same sample under theFor assay/related substances methods, the active peak andsame condition at the same time. Precision may beeach impurity should be adequately resolved from allconsidered in three levels repeatability, intermediateimpurity/degradant peaks, placeboprecision and reproducibility10.peaks,andblankpeaks. Resolution of each impurity peaks and impurity peakRepeatabilityfrom interested peak should complies US Pharmacopeia.Repeatability expresses the precision under the sameBlank, Placebo andsample matrix components should beoperating condition over a short interval of time. It is alsoanalyzed without the active present in order to identifytermed intra-assay precision. A minimum of six replicatepossible interferences.sample preparation of a same sample or homogenousIf filters are to be used to clarify sample solutions, ansample prepared at the 100% test concentration.aliquot of filtered sample diluents should be analyzed forIntermediate precisionpotentialIntermediate precision reflects within-laborator y variationsinterferences and result should compared withcentrifuged sample.If the impurities/degradants aresuch as different days, different analysts, and differentunknown or unavailable, forced degradation studies shouldequipments. Intermediate precision testing can consist of twobe performed. Forced degradation studies of the activedifferentpharmaceutical ingredient (API), placebo and finishedpreparations, as per specified analytical method. Theproduct, using either peak purity analysisanalysts execute their testing on different days usingoramassspectral evaluation, should be performed to identify andseparate the potential pleseparate instruments and analytical columns.ReproducibilityThe forced degradation studies should consist of exposingReproducibility expresses the precision of a method with inthe API, placebo and finished product to acid, base,the laboratory variationperoxide, heat, light conditions and moisture or water untilanalyst and different equipments etc. Each testing site canadequate degradation of the active has been achieved.prepare a total of six sample preparations, as per theAn acceptabl e range of degradation may be 10-30% foranalyticalmethod.assay and about 10% for related substance but maystatisticalequivalencevary based on the active being degraded. OverAcceptance criteria similar to those applied to intermediatedegradation of the active or known impurity should beprecision also apply to reproducibility.avoided to prevent the formation of secondary degradants.AccuracyIf placebo material is available, it should be stressed underAccuracy should be performed at a minimum of fivethe same conditions and for the same duration and as the APIconcentration levels, for LOQ11 and maximum concentrationand finished product. The degraded placebo samples shouldwill be six replicate preparation and median concentrationbe evaluated to ensure that an y generated degradants aremust be three replicate as per specified test method or it canresolved from the analyte and impurity peak of interest.be spiked synthetic mixture of product component and theForced degraded sample should pass the peak purity andacceptancecriteriadoes not show any purity flag by using a photodiodedetail given intable6.arrayNonSolution Stability: The solution stability is stability ofchromophoric compound or GC sample should confirm massstandard and extracted sample solution (ready to inject)detectorforchromophoric SRDE Group, All Rights Reserved.compound.like different days, differentResultsareamongevaluatedvariousto ensuretestingsites.and number sample preparationInt. J. Res. Dev. Pharm. L. Sci.1491

Daksh S. et. al., April - May, 2015, 4(3), 1489-1497from thesampleaspreparation. The low concentration solution gi ves signal tostorednoise ratio is about 10, that could be the LOQ and the lowproperly in room temperature and refrigerated conditionconcentration solution gi ves signal to noise ratio is about 3,depending upon the stability of the sample and standardthat could be the LOD of the particular impurity and itsolution.should be established for each impurities and interestedThe stability of standard and sample solution should bepeak14.established in room temperature and refrigerated, ifDOCUMENTATIONrefrigerated before analysing it should be thawing toThe validity of an analytical method should be establishedroom temperature.and verified by laboratory studies and documentation ofA minimum two preparation of standard and sample solutionsuccessful completion of such studies should be provided inshouldand analysed as per specifiedthe validation report. General and specific SOPs (standardmethod. The analysed solutions stored in necessary conditionoperating procedure) and good record keeping are anand the stability can be established for two days or solutionessential part of a validated analytical method.stability can be established by an hour basis1. Summary ndupon the nature of d development, degradation study data andRuggedness (Robustness)establishmentRobustness12, 13 of an analytical procedure measure of itsRetention Time and LOQ etc.capacity to remain unaffected by smallSummary informationbutdeliberateofRelativeRetention Factor, Relativevariation in method parameters and provides an indicationSummary information should contain detail of certificateof its reliability during normal usage. Robustness must notofnecessarily include in minivalidation or in preclinical stagestandard,validation, but in complete validation and before transferincluding analytical method development report and if anythe analytical method to another laboratories it should beminivalidation reports.established, the procedure and acceptance criteria detailin tableanalysis 8.ofreferencevalidationSummarystandard and/or workingprotocols andtablewithasummarylistreports,contains validityperiod of the certificate of analysis referenceLimit of quantification and detection (LOD and LOQ)standard and/or workingThe LOQ is the lowest amount of an analyte in a sample thatnumber should be allotted for each and ever ycan be quantitatively determined with suitable precisionmethod and the summar y report of the all theand accuracy. There are differentvalidation should be addressed in a proper way.determinationapproachestotheof LOQ. LOQ is a parameter to the quantitation of the sample at low level in the compound andis used particular for the impurities, degradation productsand/orresidualsolvents. descriptionof Aforceddegradationstabilityandresidualsol ventsaandthe incidentreport, original and repeated data detail shouldcan only be applied if there is no much baseline noise, LOQderived from the computer aided soft ware’s. For relatedstudiesA description of experiments conducted and if anyerror occurs during a validation,LOQ based on signal to noise ratio (SIN): This approachcan be calculated as per US Pharmacopoeia or it can bethe analyticalsupporting data.curve method.substanceoperationalprotocolmethod.LOD and LOQ can beestablished from signal to noise ratio method and linearityAnstandard,be covered. Documentation of intra and inter-assay precisionand accuracy.leastconcentration of impurities can be spiked in to the testsolution (if no impurities present in the test solution) or Legibleannotatedchromatogramsor massspectrograms, if applicable.synthetic mixture of product component of placebo SRDE Group, All Rights Reserved.Int. J. Res. Dev. Pharm. L. Sci.1492

Daksh S. et. al., April - May, 2015, 4(3), 1489-1497 Any deviations from SOPs, protocols, or (GoodFor this reason and the need to satisfy regulatoryLaboratory Practice) GLPs (if applicable), andauthority requirements, all analytical methods should bejustifications for deviations and the incident reportproperly validated and documented. The ai m of this articleto be captured.is to provide simple to use approaches with a correctscientific background to improve the quality of the od development and validation process. This articlemethod transfergivesin eparation, procedure and acceptance criteria for allthe commercial batch and longterm stability data therefore,ananal yticalbemethodvalidation parameters inwiderrange.produced to acceptable scientific standards.Table 1Type of analytical procedureIdentificationTest for ImpuritiesCharacteristicsQuantitationAssay DissolutionContent/potencylimitAccuracy- - Precision Repeatability I. Precisioni- - Specificity (2)- - Detection Limit- (1)- (1)Quantitation limit Linearity-- (3) -Range- ---signifies that this characteristics is not normally evaluated. signifies that this characteristics is normally evaluate d.(1) in case where reproducibility has been performed, intermediate precision is not needed.(2) Lack of spe c if ic ity of one a nalytica l procedure could be c ompensated by othe r support ing ana lyt ic al proce dure (s).(3) May be ne eded in some cases. SRDE Group, All Rights Reserved.Int. J. Res. Dev. Pharm. L. Sci.1493

Daksh S. et. al., April - May, 2015, 4(3), 1489-1497Table 2Analytical methodsParametersAssay Content Unifomity or Blend UniformityUniformity of Dosage UnitsDissolutionRelated substanceResidual solventsPrecision, Accuracy, specificity only blank and placebo interference,Linearity and solution stability.Precision, Accuracy, specificity includes forced degradation study,LO D and LOQ, Linearity and solution stability.Precision, Accuracy, specificity only blank and placebo interference,LOD and LO Q, and Linearity.Table 3: US FDA guidelines for analytical method validationS. No.Test MethodsParameter : Linearity ii1Assay2Content Uniformityor Blend Uniformity50 to 150 % of t he test concentration and correlation coefficient should obtain 0.99950% to 150 % of the test c concentration from the lower strength and correlationcoefficient should obtain 0.9993Uniformity of Dosage Units50% for m the lower strength and to 150 % of t he test concentrationfrom the higher strength (if different strengths are available) and correlationcoefficient should obtain 0.9994Dissolution50 to 150 % of the test concentration. If sustained product 10% to 150 % ofthe test c concentration and correlation coefficient should obtain 0.9995Related Substance andresidual solventsL OQ t o 300% of each known impurity and correlation coefficientshould obtain 0.95Table 4Test MethodsParameter : SpecificityAssayN o interference from blank iii, Placebo iv and degraded impurityContent Uniformity or Blend UniformityN o interference from blank and Placebo.Uniformity of Dosage UnitsN o interference from blank and Placebo.DissolutionN o interference from blank and Placebo.Related SubstanceN o interference from blank, Placebo and any degraded or any impurity.Residual solventsPercentage interference can be considered for t he final calculation if not more than2.0% for blank as well as placebo v. Above table, wider range has been selected because we could avoid reva lidation due to strength c hange or while a dding any lower strength. Diluents used for standard and test preparation. Synthetic mixture of product component except active ingredient. Synthetic mixture of product component including active ingredient. SRDE Group, All Rights Reserved.Int. J. Res. Dev. Pharm. L. Sci.1494

Daksh S. et. al., April - May, 2015, 4(3), 1489-1497Table 5Test MethodsParameter : Precision1AssaySix sample preparation to prepare as per specified method. The mean assay value andindividual assay value should obtain 95.0% to 105.0 % and percent RSD should obtain 2. 0%of six assay value and confidence intervals also can be calculated.Content UniformityBlend UniformityUniformityUnitsoforDosageTen sample preparations to prepare as per specified method and sample collected in triplicate,three different places and one pooled sample. The mean assay value and individual assayvalue should obtain 90.0% to 110.0 % and percent RSD should obtained 2.0% for ten assayvalues.Ten dosage units should prepare as per specified method. The mean assay value and individualassay value should obtain 90.0% to 110.0 % and percent RS D should obtained 2.0% for tenassay values.DissolutionSix dosage unit s should prepare as per specified method. The mean assay value and individualassay value should obtain 95.0% to 105.0vi % and percent RSD should obtained 5.0%.Related SubstanceSix sample preparation to prepare as per specified method or known impurity can be spiked.The mean and individual percentage impurity spiked ma y be 85.0% to 115.0 % and thepercent RSDResidual solventsSix sample preparation to prepare as per specified method or known solvent can be spiked. Theme an and individual percentage sol vent spiked ma y be 85.0% t o 115.0 % and the percentRSD should obtain 15.0% of individual solvents.Table: 6Test MethodsAssa y Content Uniformityor Blend UniformityUniformity of DosageUnits DissolutionParameter : AccuracyA minimum six sample preparation to prepare at lower and higher concentration, threepreparations i n the middle concentration as per specified method or active can bespiked with synthetic mixture of product component. The mean recovery value andindividual recovery value should obtain 97.0% to 103.0 % and percent RSD shouldobtain 2.0%Related SubstanceA minimum six sample preparation to prepare at LOQ level and 200% from of it andthree preparations in t he middle concentration as per specified method or impurity blendcan be spiked. The mean recovery value and individual recovery value should obtain85.0% t o 115.0 % and percent RS D should obtain 15.0%.Residual solvent sA mini mum six sample preparation to prepare at LOQ level and 300 % from of it andthree preparations in t he middle concentration as per specified method or solvent can bespiked. The mean recovery value and individual recovery value should obtain 85.0% to115.0 % and percent RSD should obtain 15.0%. SRDE Group, All Rights Reserved.Int. J. Res. Dev. Pharm. L. Sci.1495

Daksh S. et. al., April - May, 2015, 4(3), 1489-1497Table: 7Test MethodsAssay Content UniformityorBlendUniformityUniformity of DosageUnits DissolutionParameter : Solution Stability viiThe percent assay value should obtain with in 2.0% from t he initial assay value forsample preparation and 2.0% difference from the response from the initialstandard preparation.Related SubstanceThe percent total impurity value should obtain with in 0. 04% and individualimpurity within 0.02% from the initial assay value for sample preparation and 2.0% difference from t he response from t he initial standard preparation.Residual solvent sUsually organic solvents are stable there will be no significant change instability study.Table: 8Parameter : RobustnessviiiTest MethodsAssay Content Uniformityor Blend UniformityUniformity of DosageUnits Dissolution Relatedsubstance Residualsolvents ixSystemsuitabilitywithintheacceptance criteria.Table: 9Parameter : LOD and LOQxTest MethodsRelated substanceA minimum six sample preparation to prepare at Quantitation level and Detectionlevel shall be just established. The impurity blend solution can be spiked as per specifiedtest method. The mean recovery value should obtain 85.0% to 115.0 % and percent RSDshould obtain 15.0%.Residual solventsA minimum six sample preparation to prepare at Quantitation level and Detectionlevel shall be just established. The solvent blend solution can be spiked as per specifiedtest method. The mean recovery value recovery value should obtain 85.0% to 115.0 %and percent RSD should obtain 15.0%. SRDE Group, All Rights Reserved.Int. J. Res. Dev. Pharm. L. Sci.1496

Daksh S. et. al., April - May, 2015, 4(3), 1489-1497Applicationsofanalytical method and method transferare also taken into considerationvarious oncharacteristics for analytical methodology have beendiscussed with a view to improving the standardacceptance in thisareaandof 13.14.15.16.Thompson M, Ellison SLR and Wood R. HarmonisedGuidelines for single Laboratory Validation of Methodof Analysis. Pure Appl Chem. 2008;74:835-55.Wood R. How to Validate Analytical Methods. TrendsAnalyt Chem. 2005;54:149-58.Mc DowallR D. TheRole of Laboratoryinformation Management systems LIMS in AnalyticalMethod Validation. Anal Chim Acta. 2077; 54:14958.Puluido A, Ruusanches I, Boquc R and Rius FX.Uncertainty ofresultsIDroutine QualitativeAnalysis in Analytical Chemistry. J Pharm Biomed Anal.2005;22:647-54.Kallner A. Quality specification based on theuncertainty of measurement. Se and J Lab Invest.2005;59:513-6.Trullols E, Ruisanchez 1, Rius FX. Trends in AnalyticalChemistry. J Lab Invest2003;23:137-45.Valcarcel M, Cardenas S Gallego M. SampleScreening system in analytical chemistry.TrendsAnalytChem. 1999;23:137-45.Ye C, Liu J, Ren F, Okafo N. Design of tical Method Validation. J Pharm BiomedAnal. 2000;23:581-9.Bressolle F, Bromet PM, Audran M, Validation ofliquid chromatographic and gas chromatographicmethod Applications topharmacokinetics.JChromatogr2000;686: 3-10.Lindner W, Wainer IW. Requirements for initial assayvalidation and publication in J ChromatltographyB.J Chromatogr. 2006;707:1.2.11. Rodbord D, Feldrnan Y Jaffe M. Kinetics of TwoSite Immuno radiometric (Sandwich)Assay-lI.Immunochem.1995;15: 77 82.Vander HY, Nijhuis A, Verbeke JS, Vandegtnste BG,Massart DL. Guidance for roubustness/ruggedness testin method validation, J Pharm Biomed Anal.2009; 24:723-53.Validation of analytical procedure: methodologyQ2B, ICH Harmonized Tripartite Guidelines, 1996:1-8.US Pharmacopeia. 2007; 1:582-583.US Pharmacopeia. 2007; 1:680-681.GauravTiwari,RuchiTiwari.Bio analyticalmethod an updated review. Pharmaceutical Methods.2010;1:25-38. SRDE Group, All Rights Reserved.Int. J. Res. Dev. Pharm. L. Sci.1497

3. Analytical method verification or mini validation to be done before analysing (routine samples) tests like assay, dissolution and related substance in development laboratories etc. 4. Prior starting the validation the satisfactory result should be found in mini validation and formulation should be finalized3. VALIDATION

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