1. Appearance

• The medicated Gels can be examined physically for appearance like clarity, colour and presence of any particle.

2. Skin irritation

• Skin Irritation is determined by applying the gel on the skin of healthy volunteers.
  • No irritation: 0
  • Slight irritation: 1
  • Irritation: 2

3. pH

• pH of Gels can be measured using digital pH meter.
• Standard pH of gel is 5 to 5.5.

4. Viscosity

• Viscosity was determined using Brookefield viscometer.

5. Drug content

• Determined by appropriate spectrophotometrically like uvspectrophotometer.

6. Spreadability

• Spreadability is measured by spreading 0.5 g Gel on a circle of 2 cm diameter on a glass plate. Then a second glass plate is placed. 1/2 kg weight placed on the upper glass plate for 5 minutes.
• Finally diameter of circle spreading is measured.

S = ML/T

SPREADIBILITY

M= weight of an upper side
L= length of circle/ diameter
T= time in minutes

S=Spreadibility

7. Stability

• Also known as shipping test.
• It is performed to determine stability of Gel at various temperatures and RH (Relative humidity). Read more – stability Test

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Pharmaceutical Jellies