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THE GENERAL AIM OF ANALYTICAL CHEMISTRY IS TO MAKE. THE INTRINSIC BUT LATENT INFORMATION ON AN OBJECT. EVIDENT, MEASURABLE, TRUTHFUL AND USEFUL. LATENT. CHEMICAL. INTRINSIC. IDENTIFICATION. ORIGIN. INFORMATION. CHARACTERIZATION. TECHNICAL. QUALITY. BASIC. APPLIED. EVIDENT.
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M. Valcárcel Metrology in Chemistry THE GENERAL AIM OF ANALYTICAL CHEMISTRY IS TO MAKE THE INTRINSIC BUT LATENT INFORMATION ON AN OBJECT EVIDENT, MEASURABLE, TRUTHFUL AND USEFUL LATENT CHEMICAL INTRINSIC IDENTIFICATION ORIGIN INFORMATION CHARACTERIZATION TECHNICAL QUALITY BASIC APPLIED EVIDENT MEASURABLE AVAILABLE TRUTHFUL USEFUL
M. Valcárcel Metrology in Chemistry THE MAIN GOAL OF ANALYTICAL CHEMISTRY IS TO MINIMIZE UNCERTAINTY ON THE CHEMICAL INFORMATION OF A OBJECT OR A SYSTEM THREE TYPES OF CHEMICAL INFORMATION IDEAL INTRINSIC TRUENESS QUALITY INFORMATION INFORMATION REFERENTIAL Y CONSIDERED C QUALITY TO BE TRUE A Y R T N U I C A T C R A E ANALYTICAL C REAL N INFORMATION U QUALITY ROUTINELY PRODUCED
M. Valcárcel Metrology in Chemistry IS METROLOGY IN CHEMISTRY UNDER THE RESPONSIBILITY YES OF ANALYTICAL CHEMISTRY? THE EXCLUSIVE GOAL OF NO ANALYTICAL CHEMISTRY? RELATED TO THE FOUNDAMENTALS OF ANALYTICAL CHEMISTRY? YES RELATED TO THE QUALITY YES OF THE ANALYTICAL INFORMATION? NO DIRECTLY RELATED TO FITNESS FOR PURPOSE? INDIRECTLY YES
M. Valcárcel Metrology in Chemistry ANALYTICAL CHEMISTRY, TOMORROW SYSTEMATIC TREATMENT AS INFORMATION SCIENCE EXPLORATION OF ITS C I R METROLOGICAL CHARACTER E N E G DISTINCTION INTRINSIC AND SHARED FOUNDAMENTALS T R E N D S TO PROPITIATE SPECIFIC QUALITY DEVELOPMENTS AUTOMATIZATION, MINIATURIZATION, SIMPLIFICATION RESPONSIVE ANALYTICAL TOOLS P T R O O B O C A L E S S S S E I S EXPANDING BOUNDARIES C MORE EMPHASIS ON THE ANALYTICAL PROBLEM ANALYTICAL QUALITY NEW PEDAGOGICAL APPROACHES
M. Valcárcel Metrology in Chemistry ANALYTICAL CHEMISTRY TRADITIONAL METROLOGICAL APPROACH APPROACH CHANGES POSITIVE EVOLUTION TO BASIC ANALYTICAL QUALITY ANALYTICAL CHEMISTRY IS BOTH TECHNICALLY AND SCIENTIFICALLY ENRICHED (no crucial innovations are really introduced) OLD PRINCIPLES DO NOT DISAPPEAR; RATHER THEY ARE IMPROVED
M. Valcárcel Metrology in Chemistry DIFFERENCES BETWEEN CHEMICAL (CMPs) AND PHYSICAL MEASUREMENT PROCESSES (PMPs) I CMPs ARE STRONGLY SAMPLE-DEPENDENT PMPs ARE VIRTUALLY SAMPLE-INDEPENDENT QUITE SIMILAR PMPs CAN BE APPLIED TO MEASURE THE LENGTH OF A TABLE THE HEIGHT OF A TREE THE DISTANCE BET- WEEN TWO OBJECTS DIFFERENT CMPs (MAINLY THE FIRST STEP) MUST BE APPLIED FOR THE DETERMINATION OF A PESTICIDE IN WATERS (from spring to waste waters) SOILS SEDIMENTS SOILS PLANTS BIOLOGICAL FLUIDS COMMERCIALLY AVAILABLE FORMULATIONS
M. Valcárcel Metrology in Chemistry DIFFERENCES BETWEEN CHEMICAL (CMPs) AND PHYSICAL MEASUREMENT PROCESSES (PMPs) II CMPs ARE HIGHLY VARIED; BY CONTRAST, THERE ARE LESS PMPs WHICH ARE MORE GENERAL AS A CONSEQUENCE OF PRACTICAL LIMITATION OF METROLOGY IN CHEMISTRY MILLIONS THOUSANDS OF COMBINATION OF CHEMICAL FEW GENERAL CMPs ARE SAMPLE TYPES SPECIES AVAILABLE
M. Valcárcel Metrology in Chemistry DIFFERENCES BETWEEN CHEMICAL (CMPs) AND PHYSICAL MEASUREMENT PROCESSES (PMPs) III GREAT SIGNIFICANCE CMPs PRELIMINARY OPERATIONS OF IN MEASURING PROCESSES PMPs LITTLE IMPORTANCE FROM A PRACTICAL POINT OF VIEW GREAT IMPACT ON THE QUALITY OF RESULTS PMPs DATA HANDLING AND TREATMENT PO MEASURING AND TRANSDUCING THE SIGNAL RESULTS CMPs DATA HANDLING AND TREATMENT MEASURING AND TRANSDUCING THE SIGNAL PRELIMINARY OPERATIONS SAMPLE RESULTS - TEDIOUS - TIME-CONSUMING RANDOM - SOURCE OF ERRORS SYSTEMATIC - HAZARDS FOR ANALYST AND ENVIRONMENT
M. Valcárcel Metrology in Chemistry DIFFERENCES BETWEEN CHEMICAL (CMPs) AND PHYSICAL MEASUREMENT PROCESSES (PMPs) IV PMPs RELY ALMOST EXCLUSIVELY ON DIRECT-USE INSTRUMENTS MEASUREMENT EQUIPMENT ARE NOT THE SOLE FOCUS IN CMPs: MANY OTHER FACTORS AFFECT THE QUALITY OF RESULTS
M. Valcárcel Metrology in Chemistry DIFFERENCES BETWEEN CHEMICAL (CMPs) AND PHYSICAL MEASUREMENT PROCESSES (PMPs) V KEY ASPECT IN CMPs TO ASSURE REPRESENTATIVENESS SAMPLING DOES NOT EXIST OR IN PMPs IS QUITE SIMPLE HETEROGENEITY OF OBJECTS AND SAMPLES INTRODUCES SERIOUS ERRORS IN CMPs THIS PROBLEM IS ALMOST EXCLUSIVE OF METROLOGY IN CHEMISTRY
M. Valcárcel Metrology in Chemistry EXAMPLE TITRIMETRIC DETERMINATION OF CL2 (OXIDANT) Kg / MOLE SI UNITS ATOMIC WEIGHTS (I, O, K, S, Cl CHEMICAL STANDARDS STOICHIOMETRY KIO3 ANALYTICAL STANDARDS S2O32- PRIMARY 1st step IO3- + 5I- + 6H+ 3I2 + 3H2O 2nd step I2 + 2S2O32- S4O62- SECONDARY ANALYTE 1st step Cl2 + 2I- 2Cl- + I2 2nd step I2 + S2O32- S4O62- + 2I- BURETTE IO3- - 3 I2 - 6S2O32- - 6I2 - 6Cl2 ANALYTICAL STANDARDS TITRIMETRY
M. Valcárcel Metrology in Chemistry DIFFERENCES BETWEEN CHEMICAL (CMPs) AND PHYSICAL MEASUREMENT PROCESSES (PMPs) X THE EXISTENCE OF A WELL-ESTABLISHED NATIONAL AND INTERNATIONAL NETWORK OF PHYSICAL LABORATORIES IS A GREAT ADVANTAGE OF METROLOGY IN PHYSICS, THAT IN FACT DOES NOT EXIST IN CHEMISTRY I O G L C O A L R T L E A M B O L A R N A T O O I T R A I E N S BIPM • NON ACCREDITATED LABORATORIES
M. Valcárcel Metrology in Chemistry SAMPLING PRELIMINARY OPERATION OF CMPs THAT CAN SIGNIFICANTLY CONTRIBUTE TO THE UNCERTAINTIES OF RESULTS NEED TO SYSTEMATICALLY CONSIDER SAMPLING IN QUALITY SCHEMES, NORMS, GUIDES CONCERNING METROLOGY IN CHEMISTRY PRACTICAL APPROACHES TO METROLOGY IN CHEMISTRY II
M. Valcárcel Metrology in Chemistry UNCERTAINTY IS A KEY ASPECT OF TRACEABILITY: IT IS NECESSARY TO IDENTIFY ALL SOURCES OF UNCERTAINTY MAIN APPROACHES TO QUANTIFYING UNCERTAINTY IN CHEMICAL ANALYSIS FAR FROM THE REALITY IN CHEMICAL BOTTOM-UP APPROACH MEASUREMENTS - Guide to the Expression of Uncertainty in Measurements (1995) ISO - Quantifying Uncertainty in Analytical Measurement (1995) EURACHEM GLOBAL APPROACH see next transparency OTHERS PRACTICAL APPROACHES TO METROLOGY IN CHEMISTRY III UNCERTAINTY CALCULATIONS
M. Valcárcel Metrology in Chemistry PRACTICAL APPROACHES TO METROLOGY IN CHEMISTRY IV SUBSTANTIAL ESSENTIAL Y ELEMENT T ASPECT OF N OF METHOD I ANALYTICAL A VALIDATION T QUALITY R E C N U N O CALIBRATION E C N E U L ALLOWS THE F CLASSIFICATION N I OF CMPs T C E R KEY ELEMENT I D DISTINCT OF THE UNBROKEN FEATURES CHAIN OF COMPARISONS IN CMPs (TRACEABILITY) MEASUREMENT STANDARDS TWO TYPES OF PLAY AN CALIBRATION IMPORTANT PROCEDURES ROLE
M. Valcárcel Metrology in Chemistry EQUIPMENT ANALYTICAL CALIBRATION CALIBRATION CHECKING THE CORRECT CHARACTERIZING THE DEFINITION OPERATIONS OF AN INSTRUMENTAL RESPONSE INSTRUMENT OR APPARATUS IN TERMS OF ANALYTE PROPERTIES AIM EQUIPMENT TO CORRECT THE TO ESTABLISH AN UNEQUIVOCAL INSTRUMENT RESPONSE RELATIONSHIP BETWEEN SIGNALS OF THE PARAMETRIC AND ANALYTE CHARACTERISTICS REACTING OF AN FOR BOTH QUALITATIVE AND APPARATUS QUANTITATIVE PURPOSES DO NOT CONTAIN CONTAIN THE ANALYTE MEASUREMENT THE ANALYTE EXCEPT IN FACTORING STANDARDS (TITRIMETRY) P M P s C M P s
M. Valcárcel Metrology in Chemistry FIRST VALIDATION OF LEVEL METHODOLOGIES VALIDATION VALIDATION SECOND DATA OF OF ANALYTICAL LEVEL VALIDATION SAMPLING TOOLS VALIDATION VALIDATION VALIDATION THIRD OF REAGENTS, OF OF LEVEL RMs, etc. EQUIPMENTS COMPUTERS FOURTH INSTRUMENTS APPARATUS MECHANISM HARDWARE SOFTWARE LEVEL VALIDATION VALIDATION VALIDATION VALIDATION VALIDATION PRACTICAL APPROACHES TO METROLOGY IN CHEMISTRY V V A L I D A T I O N METROLOGICAL THE TWO FACETS QUALITY OF ANALYTICAL TO ASSURE QUALITY ARE FITNESS FOR INVOLVED PURPOSE ALTHOUGH METHOD VALIDATION IS THE MOST PROMINENT ACTION IN THIS CONTEXT; THERE ARE OTHER APPLICATIONS SUCH AS "DATA VALIDATION", "SOFTWARE VALIDATION", etc. THERE IS A NEED TO ESTABLISH A HIERARCHY IN THIS CONTEXT.
M. Valcárcel Metrology in Chemistry TRENDS IN METROLOGY IN CHEMISTRY SPECIFIC NORMS, GUIDES, PROTOCOLS AND DICTIONARIES ARE NEEDED IN METROLOGY IN CHEMISTRY INCREMENT OF THE LOOKING FOR AVAILABILITY OF ALTERNATIVES TO ASSURE THE REFERENCE MATRIX-TYPE METROLOGICAL CERTIFIED SUBSTANCES QUALITY OF REFERENCE ANALYTICAL RESULTS MATERIALS ESTABLISHMENT OF THE TRACEABILITY CHAIN FOR THE MOST COMMON CMPs METROLOGY OF THE DEVELOPMENT BINARY OF MORE RATIONAL RESPONSE PROCEDURES TO ESTIMATE CONSIDERATION UNCERTAINTIES IN OF SAMPLING CHEMICAL MEASUREMENTS AS A DECISIVE ACTIVITY IN METROLOGY IN CHEMISTRY PROMOTION OF CENTRES OF METHOD VALIDATION REFERENCES IN SPECIFIC AREAS OF CHEMICAL ANALYSIS INTERLABORATORY SHOULD BE ESTABLISHED EXCERCISES AND RECOGNIZED PROFICIENCY TESTING
