Introduction

On this page we describe the results for determining the solubility of HDM extracts. We have dissolved the Dermatophagoides pteronyssinus extract FD (freeze-dried) and whole culture D. farinae extract FD (freeze-dried) in 70% DMSO. We have compared this with demineralized water (demi water) and a borate buffer.

DMSO (dimethyl sulfoxide) is a organic compound which is already widely used as a polar aprotic solvent. DMSO is therefore very suitable as a solvent in chemical reactions and a large number of organic compounds dissolve well in DMSO. By using DMSO, the mass percentage of solubility of a substance can be increased for the benefit of chemical reactions. Because DMSO is low toxic ( LD50, oral, rat, 14,500 mg/kg) and increases the absorption rate of some compounds through the skin, and other organic tissues, it is also used in the medical and cosmetic industry.

Material used

  • 02.01.85, D. pteronyssinus whole culture extract FD (batch 15G10)
  • 02.02.85, D. farinae whole culture extract FD (batch 15G06)
  • DMSO (release number 13171)
  • Demineralized water
  • Borate buffer, freshly prepared

Methods

  • Make a 10%, a 5% and a 2% HDM-extract solution in demi-water, 70% DMSO and borate buffer
  • We have used the following material to create the solutions: 50 mg/ 0,5 ml = 10%, 25 mg/ 0,5 ml = 5%, 10 mg/ 0,5 ml = 2%
  • At start, Vortex and incubate at room temperature
  • Vortex before making a photo
  • Make a photo of the solutions after 5 minutes, 15 minutes and 2 ½ hour.

For comparison we have made a total picture of each batch. The tests are performed at room temperature (19- 20°C). On the next pages you can see the pictures of the solubility of the D. farinae and D. pteronyssinus extracts.

Results

Solubility of the D. farinae extract 15G06
Solubility of the D. pteronyssinus extract 15G10

Conclusion

The extracts with different concentrations is soluble in the following liquids and timeframes:

  • Demi water: the extracts are all completely dissolved within 5 minutes.
  • Borate buffer: the extracts are all completely dissolved within 15 minutes.
  • 70% DMSO: the extracts are all completely dissolved within 2 ½ hours.