SAS 2 Flashcards
It determine the mass of the analyte or some compound chemically relate to it.
Gravimetric Method
It is a substance to be determined is converted to an insoluble precipitate which is collected and weighed.
Precipitation
Analyte or its decomposing products are volatized at a suitable temperature, then collected and weighed.
Volatilization
It measure the volume of the solution containing sufficient reagent to react completely with the analyte (e.g. Acid-Base and Redox).
Volumetric/Tritimetric Method
It involves the measurement of such electrical properties as potential, current, resistance and
quantity of electrical charge.
Electroanalytical Method
Measurement of current as a function of the applied voltage and reveals the reduction potential of an analyte.
Voltammetry
Measurement of current and time needed to complete an electrochemical reaction and reveals concentration
of an analyte.
Coulometry
Measurement of potential of an ion electrode in equilibrium with an ion to be determined and reveals concentration of an analyte.
Potentiometry
It is based on the measurement of the interaction between electromagnetic radiation and analyte atoms or molecules or on the production of such radiation by analytes.
Spectroscopic Methods
Ionization of molecules introduced into a Mass Spectrometry (MS) involves ionization of
molecule in the gas phase according to their mass to charge ration (m/z). This assay is commonly used to test for electrolytes.
Ion-selective Electrodes (ISE)
It is use to identify and quantify volatile substances such as alcohols. For toxicological
screening of organic acids, and drugs (e.g. steroids, benzodiazepines and tricyclic antidepressant). Has similar principle with
thin layer chromatography but instead of solvent, GC utilizes an inert gas (e.g. helium, nitrogen) as a carrier for the volatile
substance.
Gas Chromatography (GC)
It is widely used, especially in forensic laboratories, for
toxicological screening , amino acids and drugs (e.g. indomethacin, anabolic steroids, cyclosporine). It has similar principle with GC but it is useful in non-volatile or heat sensitive substance but instead of gas, HPLC utilizes a liquid solvent (mobile phase) and a column packed with a stationary phase (e.g. silica base).
High Performance Liquid Chromatography (HPLC)
It is a heterogeneous Enzyme Immunoassay (EIA) which employs the
same basic principles as Radioimmunoassay (RIA) except that enzyme activity rather than radioactivity is measured. This assay is commonly used in serologic tests to determine antibodies directed against a wide range of antigens such as rheumatoid factor, hepatitis B antigen, other bacterial and viral antigen (e.g. cytomegalovirus, HIV) in the serum.
Enzyme-linked Immunosorbent Assay (ELISA)
It is a homogeneous EIA in which the enzyme is used as a label for a specific analyte especially in testing general chemistries (e.g. albumin, BUN, creatinine, glucose, cholesterol, bilirubin, total protein), enzymes (e.g. acid and alkaline phosphatase, amylase, creatinine kinase), coagulation factors (e.g. antithrombin III,
fibrinogen, degradation products, heparin, plasminogen) and some drugs for therapeutic drug monitoring (e.g.
aminoglycosides, vancomycin, digoxin, antiepileptics, antiarrhythmics, theophylline) and for drug level toxicology (e.g.
acetaminophen, salicylate, barbiturates, TCAs, amphetamines, cocaine, opiates).
Enzyme Multiplied Immunoassay (EMIT)
The most common form of immunoassay, is used to measure
concentrations of many serum analytes such as BUN and creatinine. This assay is commonly used for therapeutical drug
monitoring of some drugs (e.g aminoglycosides, vancomycin, antiepileptics, antiarrhythmics, theophylline, methotrexate,
digoxin, cyclosporine), general chemistries and enzyme (e.g., thyroxine, triiodothyronine, cortisol, amylase, BUN, lactate
dehydrogenase, creatinine, glucose, cholesterol and iron).
Fluorescent Polarization Immunoassay (FPIA)
