Stock solution

Overview :

  • Stock solution can be defined as a highly concentrated solution, mostly prepared as 10X concentrated, which can be diluted to prepare working solution.
  • Stock solution is also used as a component to prepare complex solution containing many ingredients. For example, stock solution of EDTA (0.5 M EDTA solution) can be used to prepare many solutions including TAE, TBE, Tris-EDTA, Trypsin-EDTA etc.

Advantages :

  • Since stock solution is highly concentrated, its storage requires less space.
  • It is also convenient to transport stock solution due to its small volume.
  • The concentration of various component of working solution is more accurate when it is made from stock solution rather than individual component from its original form.
  • Stock solutions which contains any active biological substances (e.g., enzymes, inhibitors, DNA, RNA etc.) are more stable in highly concentrated form.

Disadvantages :

  • Since stock solution is highly concentrated, often to dissolve them requires more time and effort. Sometime, heating of solution is required to dissolve the substance completely.
  • Long term storage of stock solution (especially salt solution, at cold room) may leads to precipitation of solute.