Laboratory reagents

QUALITY OF REAGENTS

A same product comes in many different forms and quantities depending on the manufacturer. Quality standards, corresponding to various degrees of purity, and therefore to different purposes, allow to differentiate them:

  • No specification
  • Pure, ultra pure, very pure
  • For analysis or PA
  • According to pharmacopoeia
  • For synthesis, chromatography, etc.

According to their use on the field (See Updated laboratory procedures, MSF, 2022), MSF selected products which are meeting the following criteria:

  • Quality ensuring a very good result
  • Best price
  • Available in small packaging

3 quality standards have been selected:

  • No specification (general use)
  • Pure, ultra pure, very pure (specific pharmacopoeia use)
  • For analysis (organic analyses and syntheses)

Concerning staining products, the quality standards "for bacteriology" or "for microscopy" correspond exactly to the specifications of solutions and reagents prepared in laboratories equipped by MSF.

Quality standards "for synthesis" or "for chromatography" are indicating a very high degree of purity, with the level of residues following analysis on the label. They are more expensive and should not be ordered.

USE OF POWDERS

The decision to use powders for the preparation of reagents should only be taken until a careful study of the laboratory to be equipped has been made.

It is recommended to use ready to use reagents in liquid form if available, because the preparation of reagents or staining products from powder requires additional equipment (test tubes, flasks, scales etc.), complementary reagents (alcohol, phenol, etc.)and well-trained laboratory personnel.

PACKAGING OF REAGENTS

Powders

It is recommended to always select the smallest possible packaging, since powders are used only in very small quantities (especially staining products).

A 100 g bottle can last for several years.

Liquids

In 500 ml or 1 l bottle, but there are exceptions.

Bottles are designed to preserve the product as best as possible (e. g.: Lugol in brown glass bottle for protecting it from light).

Always screw the bottle caps tightly.

EXPIRATION OF REAGENTS

  • Reagents should not be used beyond the expiry date indicated on the package.
  • Reagents with no expiry date should be regularly controlled for their quality, e.g. by staining a known sample.
  • If no expiry date is indicated, the reagents can be used until empty but a quality check is required for these reagents. Indicators for expiration can be (but don't have to be):
    • Change of colour
    • Precipitation in a liquid reagent

STORAGE CONDITIONS

  • Follow the manufacturer's instructions
  • Always protect reagents from heat, light and humidity
  • For safety reasons, bottles should be stored in the lower shelves
  • If possible, store toxic reagents in a laboratory cabinet with a lock.

TRANSPORT OF REAGENTS

International transport

Chemical dangerous products must be labelled, wrapped, packaged and labelled in accordance with the IATA (International Air Transport Association) standards.

The technical sheets of the concerned products mention the air freight code (UNxxxx) as well as the hazard symbol(s).

This information should appear on the packaging, necessarily in English and in well defined dimensions.

National transport

For any transport, the reagents must be packaged and labelled in accordance with the instructions given on their technical sheet. It is recommended to keep them in their original packaging until final destination.

Follow IATA regulations for any shipment by air.

HAZARD IDENTIFICATION

New CLP classification (Classification - Packaging - Labelling) according the EC Regulation N°1272/2008 (GHS/SGH):

  • Classification categories
  • Hazard pictograms
  • Signal word
  • Hazard and precautionary statements

HAZARD PICTOGRAMMES

Image

MANAGEMENT OF LABORATORY WASTE

Management of laboratory waste should be planned on a case-by-case basis according to the specific activities of the laboratory. Treatment and/or final disposal of (hazardous) laboratory waste will depend on local conditions, availability of treatment options and the waste’s characteristics, packaging, volume and recurrence. Safety, environmental and cost factors also need to be considered.

Existing applicable national, regional or local regulations for treatment and disposal of hazardous waste should always be adhered to. It is recommended to investigate if there are specialized institutions for waste elimination and/or recycling facilities available. If facilities are substandard, the MSF alternatives can be proposed and/or lobbying by WHO or MSF can be done to improve the elimination procedures within the legislation. When legislation is non-existent, the MSF strategy will most probably have to be implemented.

Please contact your laboratory and/or WatSan advisor for support on the management of waste in your laboratory.