MODULE 1 - INTRODUCTION TO CLINICAL CHEMISTRY

It is the amount of light that is absorbed by analyte in a solution; it is directly proportional to the concentration of analyte

Absorbance

State of decrease of basic compounds and an accumulation of acid compounds in the blood causing a decrease in pH

Acidosis

Ability of a test to obtain the known target value for a sample; this helps exhibit minimal bias and imprecision

Accuracy

Attractive force between substances or particles that causes them to enter into and remain in chemical combination

Affinity

A measured portion of a sample

Aliquot

State of excess of basic compounds or loss of acidic compounds in the blood causing an increase in pH

Alkalosis

Organic acid that is the building block for proteins

Amino acid

Substance that is being measured

Analyte

All procedures related to the testing of a sample for an analyte

Analytical phase

A spectrophotometric method in which the analyte is an element, and it absorbs light at a specific wavelength. Decreases in light intensity hitting a photodetector corresponds to increased analyte concentrations

Atomic absorption

Average affinity of a mixture of antibody to their corresponding antigen

Avidity

A laboratory grade water and other reagents are set up and tested as though it was another sample. This checks for background interference from reagents and allows for correction

Blank

A liquid that resists change in pH when an acid or base is added. It consists of a weak acid and it conjugate base.

Buffer

The process of using calibrators to construct a curve used to quantitate analyte concentration in unknown specimens

Calibration

Substance that accelerates a chemical reaction, such as enzyme in the body

Catalyst

An ion carrying a positive charge

Cation

Electrode which gains electrons or is reduced. It is where reduction occurs in an electrochemical cell

Cathode

A process used to separate or concentrate material suspended in a liquid medium by use of the centrifugal force

Centrifugation

Amount of analyte measured in a sample expressed quantitatively

Concentration

A serum based material with assigned target values and acceptable range to evaluate the accuracy and reproducibility of a diagnostic assay

Control

A reaction vessel used in photometric analyzers

Cuvette

A drying agent or substance capable of absorbing moisture

Dessicant

A sealed chamber in which samples can be dried in the presence of a dessicant

Dessicator

Is the movement of particles from an area of higher concentration to one of lower concentration

Diffusion

When a solvent is added to a solution, making it less concentrated.

Dilution

It is when a chemical reaction breaks a compound into two or more parts.

Dissociation

Is when a gas moves through an opening into a low-pressure container. It occurs more quickly that diffusion because additional molecules aren’t in the way

Effusion

An ionic compound that dissolves in water to produce ions, which can conduct electricity.

Electrolyte

Protein in the body that acts as a catalyst and converts substrate to product

Enzyme

A measure of the amount of enzyme catalytic activity found in a sample

Enzyme Activity

Occurs in reversible reactions when the forward rate of the reaction is the same as the reverse rate of the reaction

Equilibrium

Fluid which has leaked out of a tissue or capillary, usually in response to inflammation of injury

Exudate

A lipoprotein particle found in blood that is composed of a high proportion of protein with little triglycerides and cholesterol, and is associated with reduced risk of atherosclerosis

High Density Lipoprotein

Hemolysis, icterus and lipemia; the most common interferents found in blood specimens

HIL

A chemical substance or compound having a physical property that changes abruptly, usually color, near the endpoint or equivalence point of a chemical reaction

Indicator

Assay that relies on an antigen-antibody reaction. Intracellular: component found inside the cell

Immunoassay

A potentiometric device used to selectively measure individual electrolytes such as Na, K, and Cl

Ion-Selective Electrode (ISE)

Lipoprotein particle found in the blood composed of protein, with little triglycerides and high proportion of cholesterol, and is associated with increased risk of developing atherosclerosis

LDL (Low Density Lipoprotein)

Milky coloration of plasma caused by increased lipid accumulation, usually triglycerides.

Lipemia

The common analytes of cholesterol and triglycerides and related compounds such as free fatty acids and lipoproteins

Lipids

The curved surface of a liquid

Meniscus

Products of anabolism and catabolism; analytes created by synthesis in the body or breakdown

Metabolites

The basic measurement principle or technique that is used in an analytical system to perform a test

Method/methodology

A force that moves water or another solvent across a membrane separating a solution. Usually, the movement is from the low to the higher concentration

Osmotic Pressure

Measuring light intensity at various wavelengths

Photometry

Lipid deposits in arteries causing stenosis and leading to cardiovascular disease

Plaque

The clear, yellow fluid obtained when blood is drawn into a tube containing anticoagulant; the clotting factors have not been activated and a clot is not formed

Plasma

All procedures related to specimen handling and result reporting after the analytical (testing) phase

Postanalytical phase

All procedures related to specimen collection and handling that precede the analytical (testing) phase

Preanalytical phase

The reproducibility of a test; the ability to obtain very similar quantitative values on repeat testing of a sample.

Precision

Use of scientific method to maintain the most accurate data possible. Procedure performed to check against a standard, such as blanks, duplicates, and spikes

Quality control

A chemical mixture to which a sample is added to conduct a test

Reagent

The expected normal concentration range for an analyte in a patient population; often varies with age, gender or other partitioning factors

Reference interval

The specimen after preparation for analysis

Sample

Liquid portion of plasma that remains after clot is removed

Serum

The ability to detect small quantities of a measured component

Sensitivity

The substance that gets dissolved in a solvent. Usually, it refers to a solid that is dissolved in a liquid. If you are mixing two liquids, the solute is the one that is present in a smaller amount

Solute

Is the liquid that dissolves a solute in solution. Technically, you can dissolve gases into liquids or into other gases, too. When making a solution where both substances are in the same phase, the solvent is the largest component of the solution

Solvent

The type of biologic fluid in which the analyte is found or the form in which the fluid is tested

Specimen

Measuring light intensity at various wavelengths

Spectrophotometry

Are samples for which the analyst knows the true value before running the test. This can be made in-house or purchased from laboratory supply companies. They are often used to calibrate instruments and to evaluate the accuracy of an analysis

Standard

The amount of antibody found in a specimen as a result of exposure to an antigen; a high ___ typically occurs after an immune response and the ----- decreases over time after exposure to the antigen

Titer

Analysis of therapeutic drugs or drugs of abuse

Toxicology

Anchoring the calibrators of a test method to recognized reference materials and/or reference methods to ensure accuracy of results

Traceability

The aqueous waste fluid produced by the kidneys

Urine

The next most common body fluid after blood used for testing

Urine

The light-scattering property associated with suspended particles in a liquid.

Turbidity

A turbid solution appears what?

Cloudy