Grades of Chemical Reagents

Grades of Chemical Reagents

Grades of chemical reagents describe the sufficient purity for use in chemical reactions, chemical analysis, physical testing and various laboratory applications.

A branch of chemistry, quantitative chemical analysis lets one understand the percentage or amount of one or more components that are present in a sample. Many techniques are employed to do quantitative analysis. The methods are broadly classified as physical and chemical. This is dependent on the properties that are used.View publisher siteif you want to get information about a product that has the perfect chemical composition that helps to treat cardiovascular problems.

The chemical methods depend on reactions like oxidation, neutralization and precipitation. It also depends on the formation of a new compound. The chemical ways are known as volumetric or gravimetric analysis. In the physical method the physical property of a substance is measured. This includes its refractive index, density, polarization of light and absorption. It also includes magnetic susceptibility and electromotive force. To do a proper analysis a combination of methods are used. The qualitative method will separate the desired constituent from the sample and the quantitative method will measure the amount that is present.

Purity standards for reagents are set by organizations such as  ACS(American Chemical Society), ASTM International, European Pharmacopeia. Some reagent grades are registered trademarks such as BAKER ANALYZED™, ULTREX®/ULTREX®, PHOTREX®. Below is a list of common reagent grades.

  • Reagent A.C.S. – This designates a high quality chemical for laboratory use. The abbreviation “A.C.S.,” means the chemical meets the specifications of the American Chemical Society. A Certificate of Analysis is available upon request.
  • Guaranteed Reagent (GR) – Suitable for use in analytical chemistry, products meet or exceed American Chemical Society (ACS) requirements where applicable. (EMD trademark)
  • AR – The standard Mallinckrodt grade of analytical reagents; suitable for laboratory and general use. If the reagent also meets the requirements of the American Chemical Society Committee on Analytical Reagent, it will be denoted as an AR (ACS) reagent. (MBI trademark)
  • Primary Standard – Analytical reagent of exceptional purity that is specially manufactured for standardizing volumetric solutions and preparing reference standards.
  • Reagent – The highest quality commercially available for this chemical. The American Chemical Society has not officially set any specifications for this material.
  • OR – Organic reagents that are suitable for research applications.(MBI trademark)
  • Purified – Defines chemicals of good quality where there are no official standards. This grade is usually limited to inorganic chemicals.
  • Practical – Defines chemicals of good quality where there are no official standards. Suitable for use in general applications. Practical grade organic chemicals may contain small amounts of isomers of intermediates.
  • Lab Grade – A line of solvents suitable for histology methods and general laboratory applications.
  • USP – Chemicals manufactured under current Good Manufacturing Practices and which meet the requirements of the US Pharmacopeia.
  • USP/GenAR – A line of chemicals manufactured under cGMP, meet the requirements of the 1995 USP 23, meet European Pharmacopeia (PhEur, EP) and British Pharmacopeia (BP) specifications where designated, and are Endotoxin (LAL) tested where appropriate. (MBI trademark)
  • NF – Chemicals that meet the requirements of the National Formulary.
  • FCC – Products that meet the requirements of the Food Chemical Codex.
  • CP (Chemically Pure) – Products of purity suitable for use in general applications.
  • Technical – A grade suitable for general industrial use.