PREPARATION OF CALAMINE LOTION
AIM:
To prepare and submit 20 ml of Calamine lotion I.P.
MATERIALS REQUIRED:
Calamine, Zinc oxide, Bentonite, Sodium citrate, Liquefied Phenol, Glycerine, Rose
water.
PRINCIPLE:
Lotions are usually liquid preparations or dispersions meant for application to the
skin without friction. Calamine is composed of zinc oxide with small amount of ferric
oxide which imparts characteristic pink colour and is used topically as protective.The
powder is used as an astringent and have weak antimicrobial action due to release of zinc
from zinc oxide which is formed by hydrolysis of acidic skin moisture. Bentonite is a
natural colloidal hydrated aluminium silicate. It is a pale buff coloured powder and is
insoluble in water, swells nearly 12 times of its bulk which imparts desirable rheological
characteristics. Hence it is used as a suspending agent. Sodium citrate acts as a buffering
agent and maintains pH appropriate for skin.It also imparts better consistency to the
product and prevents excessive frothing on shaking.It also prevents discoloration of the
product which occurs due to oxidation of ferric to ferrous oxide. Liquified phenol acts as
an antiseptic, preservative and local anaesthetic. Glycerine is used for its soothing action
and makes the preparation more viscous where as rose water gives pleasant smell to the
product.
PROCEDURE:
1. Triturate Calamine, Zinc oxide and Bentonite in a solution of sodium citrate in about
¾ th quantity of rose water.
2. Add Liquefied Phenol and glycerine to above mixture and mix well.
3. Add sufficient rose water to produce the required volume.
4. Preparation is shaken to ensure uniform distribution. Finally the transfer the
preparation into a bottle, capped, properly labeled and submitted.
Formula:
Ingredients Quantity
Calamine 15 g
Zinc oxide 5.0 g
Bentonite 3.0 g
Sod. Citrate 0.5 g
Liquefied Phenol 0.5 g
Glycerine 5.0 ml
Rose water q.s. 100 ml
REPORT
EVALUATION OF CALAMINE LOTION
AIM:
To evaluate the physical stability of suspensions prepared using different suspending
agents.
PRINCIPLE:
Physical stability of suspension is evaluated by measuring the sedimentation volume and
redispersibility studies.Sedimentation Volume (F) is the ratio of ultimate volume of
sediment to the total volume of the suspension.
F=Vu/Vo
Sedimentation volume is normally less than 1.when F=1 then such suspensions are
pharmaceutically acceptable.When F>1,it indicates that the network of flocs formed in
the suspension is loose and fluffy that it encompasses a volume greater than the original
volume of the suspension.Redispersibility is one of the major considerations in assessing
the acceptability of the suspension.Since the sediment formed should be easily dispersed
by moderate shaking,measurement of sedimentation volume and its ease of redispersion
are common procedures for evaluation.
PROCEDURE:
1. Prepare four different formulations of suspension using Bentonite,Guar
gum,Hydroxy Propyl methyl cellulose and Ethyl cellulose.
2. Pour the formulation into measuring cylinder and keep aside undisturbed.
3. Calculate the F value for all the formulations for one hour(every 10 mins) and 24 th
hour
4. Carry out redispersibility studies after 24hours
5. Conclude the most stable suspension based on F value and its ease of redispersion.
REPORT
