BASIC PRINCIPLES AND PRACTICES OF CLINICAL CHEMISTRY

Systeme International d’unites (SI)

System of units adopted internationally and preferred in scientific literature and clinical laboratories and is the only system employed in many countries

Metric system

SI system units are based on what?

Meter (m)

Basic unit for length

Kilogram (kg)

Basic unit for mass

Mole (mol)

Basic unit for quantity of a substance

Derived unit

Derivative or a mathematical function describing one of the basic units

Second (s)

Basic unit for time

Ampere (A)

Basic unit for eletric current

Kelvin (K)

Basic unit for thermodynamic temperature

Candela (cd)

Basic unit for luminous intensity

Hertz (Hz)

Selected derived unit of frequency

Newton (N)

Selected derived unit of force

Degree celsius

Selected derived unit of celsius temperature

Katal (kat)

Selected derived unit of catalytic activity

60 s (min)

Selected accepted non-SI unit of minute

3,600 s (h)

Selected accepted non-SI unit of hour

86,400 s (d)

Selected accepted non-SI unit of day

Atto (a)

Prefix of 10 (^-18)

femto (f)

Prefix of 10 (^-15)

Pico (p)

Prefix of 10 (^-12)

Nano (n)

Prefix of 10 (^-9)

Micro

Prefix of 10 (^-6)

Milli (m)

Prefix of 10 (^-3)

Centi ( c )

Prefix of 10 (^-2)

Deci (d)

Prefix of 10 (^-1)

Deka (da)

Prefix of 10 (^1)

Hecto (h)

Prefix of 10²

Kilo (k)

Prefix of 10³

Mega (M)

Prefix of 10 (^4)

Giga (G)

Prefix of 10 (^9)

Tera (T)

Prefix of 10 (^12)

Peta (P)

Prefix of 10 (^15)

Exa (E)

Prefix of 10 (^18)

0.000001

Select decimals of micro

0.001

Select decimals of milli

0.01

Select decimals of centi

0.1

Select decimals of deci

1.0

Select decimals of liter, meter, gram

10.0

Select decimals of deka

100.0

Select decimals of hecto

1000.0

Select decimals of kilo

Analytes

Specific chemical substance, ion, or component that you want to measure or study in a laboratory test

Analytic reagent

High-purity chemical substance with tightly controlled impurity limits typically exceeding 99% purity

Reagent

Substance or compound added to a system to cause a chemical reaction, test if on occurs or detect the presence of other substances

Ultrapure chemicals

Been put through additional purification steps for use in specific procedures such as chromatography, atomic absorption, immunoassays, molecular diagnostics, standardization, or other techniques that require extremely pure chemicals

Ultrapure chemicals

These reagents may carry designations of HPLC or chromatographic on their labels and are highly refined substances with impurity levels in the parts-per-billion (ppb) or parts-per-trillion (ppt) range

United states pharmacopeia (USP) and National Formulary (NF)

Used to manufacture drugs, the limitations established for this group of chemicals are based only on the criterion of not being injurious to individuals

United states pharmacopeia (USP) and National Formulary (NF)

Chemicals in this group may be pure enough for use in most chemical procedures; however, it should be recognized that the purity standards are not based on the needs of the laboratory and, therefore, may or may not meet all assay requirements

Chemically pure

Indicate the impurity limitations are not stated and that preparation of these chemicals is not uniform

Melting point analysis

Often used to ascertian the acceptable purity range

Spectroscopic reagents

Spectrally pure reagent whose purity levels are attained by their respective procedures

Chemically pure reagent

Reagents which approaches the purity level of reagent grade chemicals

Chromatographic reagent

Minimum purity of 99% determined by gas chromatography reagent

Reagent grade

Which is certified to contain impurities below certain levels established by ACS (american chemical society)

Material safety data sheet

Document that the manufacturer is required to provide technical data sheets for each chemical manufactured on a document

Clinical chemistry

Involved in the analysis of biochemical by-products found in biological fluids, such as serum, plasma, or urine, making purification and a known exact composition of the material almost impossible

Primary standard

Highly purified chemical that can be measured directly to produce a substance of exact known concentration and purity

100 + 0.02%

ACS purity tolerances for primary standards

Standard reference materials

Specialized, highly homogenous and stable substance or artifact with certified property values

Secondary standard

Substance of lower purity with its concentration determined by comparison with a primary standard

Secondary standard

Depends not only on its composition, which cannot be directly determined, but also on the analytic reference method

Water

Most frequently used reagent in the laboratory

Distilled water

Water solely purified by distillation results in what?

Deionized water

Water purified by ion exchange produces what?

RO water

Reverse osmosis, which pumps water across a semipermeable membrane, produces what?

Ultrafiltration

Pressure-driven treatment process using a semi-permeable membrane with pore sizes of 0.01 to 0.1 microns

Reagent grade water

Classified into one of six categories based on the specifications needed for its use rather than the method of purification or preparation

Clinical laboratory reagent water

Special reagent water

Instrument feed water

Water supplied by method and manufacturer

Autoclave and wash water

Commercially bottled purified water

Reagent grade water categories:

Resistivity

Measure of resistance in ohms and influenced by the number of ions present

Type i water

Water that has the most stringent requirements and generally suitable for routine laboratory use

Prefiltration

Remove particulate matter form municipal water supplies before nay additional treatments

Filtration catridges

Composed of glass; cotton; activated charcoal, which removes organic materials and chlorinel and submicron filters, which remove any substances larger than the filter’s pores, including bacteria

Glass or cotton filter

Hard water require prefiltration with what filter/s?

Condensation

In distillation, what water is collected from the process?

No

Is deionized water pure or sterile?

Present organic material

Why is deionized water neither pure nor sterile?

Deionized water

Produced using either an anion or a cation exchange resin, followed by replacement of the removed ions with hydroxyl or hydrogen ions

Reverse osmosis

Process that uses pressure to force water through a semipermeable membrane, producing water that reflects a filtered product of the original water

Reagent grade water

Obtained by initially filtering it to remove particulate matter, followed by reverse osmosis, deionization and a 0.2 mm filter or more restrictive filtration process

Type III (autoclave wash water)

Acceptable for glassware washing but not for analysis or reagent preparation

Type II water

Acceptable for most analytic requirements, including reagents, quality control and standard preparation

Type I water

Used for test methods requiring minimum interference, such as trace metal, iron, and enzyme analyses

Linear

Relationshop of water purity to resistance is what?

Increases

If purity increases, resistance increases or decreases?

solute

Substance that is dissolved in a liquid

Analytes

Biological solutes are also known as what?

Solvent

Liquid in which the solute is dissolved

Solution

Solute and solution together creates what?

Percent solution

Expressed as equal parts per hundred or the amount of solute per 100 total unit of solution

Molarity (M)

Expressed as the number of moles per 1 L of solution

Moles/liter (mol/L)

SI unit of molarity

Molality (m)

Represents the amount of solue per 1 kg of solvent

Moles/kilogram (mol/kg)

SI unit of molality

Normality

Least likely of the four concentrations expressions to be encountered in clinical laboratories but it is often used in chemical titrations and chemical reagent classification

Normality

Defined as the number of grams equivalent weights per 1 L of solution

Equivalent weight

Equal to the gmw (gram-molecular weight) of a substance divided by its valence

Valence

Number of units that can combine with or replace 1 mole of hydrogen ions for acids and hydroxyl ions for bases and the number of electrons exchanged in oxidation-reduction reactions

Valence

Number of atoms/elements that can combine for a particular compound; therefore, the equivalent weight is the gram combining weight of a material

Equal or greater than

Normality is what than the molarity?

Dilute solution

There is relatively little solute or one which has been made to a lover solute concentration per volume of solvent as when making a dilution