Instability Troubleshooting Guide- Part II

This informative summary is the second part for “Full Stability Study & Troubleshooting Guide”, serving as a practical handbook for formulators, R&D professionals, and anyone passionate about the technical foundation of cosmetics, focusing on different forms of instability with corrective & preventive actions.

·      Chapter (1) non-conforming stability results:

• Out of Specification (OOS) results.
• Considerations for preventing OOS results.
• Obvious errors in pH & Viscosity measurements.

·       Chapter (2) pH Changes:

• Optimum pH ranges for different cosmetic products.
• pH-dependent active ingredients.
• pH-sensitive preservatives.
• pH-sensitive thickeners & surfactants.
• pH-sensitive functional ingredients.
• Causes & consequences of pH changes.
• pH-related emulsion failure.

·      Chapter (3) Viscosity Changes:

• “Viscosity increases” Vs “Viscosity decreases”.
• How to minimize viscosity changes over time.

·      Chapter (4) Sedimentation problem:

• Anti-settling agents & preventing sedimentation.

·      Chapter (5) Color Changes & Discoloration Problem:

• Main causes of color changes.
• Most problematic products susceptible to color change.
• How to prevent color changes in different cosmetic products.

·      Chapter (6) Microbial Failure:

• Most common causes of microbial failure.
• How to prevent microbial failure.

·      Chapter (7) Water Quality affecting product’s stability:

• How water quality affects product’s stability & efficacy.
• Water treatment processes.
• Key considerations for choosing appropriate water specifications.

·      Chapter (8) Packaging instability:

• Stability testing for packs.
• Why packaging materials must be included in stability study.
• 7 rules for packaging material selection.
• Forms of packaging instability (& how to prevent).