In this presentation viewers will able to learn about various types of mixtures, methods of preparation of mixtures and their formulation.

1. MONOPHASIC LIQUID
DOSAGE FORM
Part-2
Mrs. Sandhya R. Lanke (Lecturer)
SJVPM’S Rasiklal. M. Dhariwal
College of Pharmacy,
Chinchwad, Pune

2. Learning Outcomes
After watching this presentation, you will be able to;
1. Define Mixtures
2. Discuss Methods of preparation of Mixtures
3. Compare Diffusible and In diffusible solids
4. Discuss formulation of Mixtures

3. MIXTURES
 A mixture is a liquid
preparation meant for oral
administration in which
medicament or medicaments
are dissolved, suspended or
dispersed in a suitable vehicle.

4. CLASSIFICATION OF MIXTURES
1. Simple mixture containing soluble substances
2. Mixture containing diffusible solids
3. Mixture containing indiffusible solids
4. Mixture containing Precipitate forming liquids
5. Mixture containing Slightly soluble liquid

5. SIMPLE MIXTURE CONTAINING
SOLUBLE SUBSTANCES
 It contains only soluble ingredients.
 It is represented by true solution .
 It is a clear homogenous mixture.
E.g. Carminative mixture, Expectorant mixture etc.

6. Method of dispensing:
1. Dissolve Solid in 3/4th Vehicle.
2. Examine the solution by holding against light .
3. Filter if any foreign particles find, Add other ingredients
5. Add more vehicle to produce final volume
6. Fill in bottle, Cork it and Clean the bottle.
8. Attach label wrap bottle and dispense.
SIMPLE MIXTURE CONTAINING
SOLUBLE SUBSTANCES

7. Rx
Ferric ammonium chloride ---- 2 drachms
Chloroform Water ----------- 1 fluid ounce
Direction: One tablespoonful to be taken three times
after meals
Method of dispensing: Simple mixture method.
SIMPLE MIXTURE CONTAINING
SOLUBLE SUBSTANCES

8. MIXTURE CONTAINING DIFFUSIBLE
SOLIDS
 Diffusible solids are insoluble in water.
 Uniformly dispersed in the vehicle on shaking.
 No need of suspending agent.
Ex. Bismuth carbonate, Bismuth subnitrate,
Magnesium carbonate.

9. MIXTURE CONTAINING DIFFUSIBLE
SOLIDS
Method of Dispensing:
1. Powder drug in mortar, add soluble drug and mix.
2. Measure 3/4th of vehicle. Make smooth cream by portion
of vehicle.
3. Transfer content from mortar into a measuring vessel, Add
any liquid ingredient.
4. Add more vehicle to produce final volume.
5. Fill in bottle, Cork it.
6. Attach label with direction“ Shake well before use” wrap
bottle and dispense.

10. MIXTURE CONTAINING DIFFUSIBLE
SOLIDS
Drug+ soluble material + Vehicle a part from 3/4th
↓ Smooth cream
Add remaining vehicle from 3/4th
↓
Add to measure
↓
Add other liquid ingredient
↓
Strain through muslin cloth for removal of foreign particles
↓
Make up the volume with remaining vehicle

11. MIXTURE CONTAINING DIFFUSIBLE
SOLIDS
Rx
Magnesium sulphate 15.0 g
Magnesium carbonate 2.0 g
Peppermint water 90.0 ml
Prepare a mixture.
Direction : One teaspoonful to be taken two hours before
breakfast.
Method of Dispensing: Diffusible mixture

12. MIXTURE CONTAINING INDIFFUSIBLE
SOLIDS
 Indiffusible solids are insoluble in vehicle.
 Not evenly distribute throughout the vehicle on shaking
or not distribute in vehicle for sufficiently long time.
 So suspending agents are added in formulation..
Ex. Acetyl salicylic acid, Phenacetin, chalk powder.

13. MIXTURE CONTAINING INDIFFUSIBLE
SOLIDS
Selection of Suspending Agents:
Compound Tragacanth Powder(CPT) :
It content 20% acacia, 15% tragacanth, 20% starch and
45% sucrose.
It is used in the proportion of 2g/100 ml of the mixture.
It is used when the vehicle is other than water or
chloroform

14. Tragacanth mucilage:
It is used in the proportion of 1/4th of the volume of the
mixture.
It is used when the vehicle is water or chloroform water.
MIXTURE CONTAINING INDIFFUSIBLE
SOLIDS

15. Tragacanth mucilage:
It is used in the proportion of 1/4th of the volume of the
mixture.
It is used when the vehicle is water or chloroform water.
MIXTURE CONTAINING INDIFFUSIBLE
SOLIDS

16. 1st Method:- When Tragacanth Powder is used
1. Finely powder diffusible, indiffusible solid and soluble
solids mixed them with tragacanth powder
2. Measure 3/4th of the vehicle triturate it with a portion of it
till there is formation of cream. Then add remaining
vehicle.
3. Examine the contents for foreign particles, if present filter
through muslin cloth.
MIXTURE CONTAINING INDIFFUSIBLE
SOLIDS

17. 4. Add any liquid ingredients if present.
5. Transfer the mixture to a measuring cylinder and make up
the volume.
6. Transfer to suitable container, cork and label with “Shake
well before use “ direction.
MIXTURE CONTAINING INDIFFUSIBLE
SOLIDS

18. 2nd Method:- When Tragacanth mucilage is used
1) Finely powder diffusible, indiffusible solid and soluble
solids mixed them
2) Triturate the material with tragacanth mucilage (1/4th of
the volume) to form smooth cream. Then gradually dilute
with ½ of the vehicle.
3) Examine the contents for foreign particles, if present filter
through muslin cloth.
MIXTURE CONTAINING INDIFFUSIBLE
SOLIDS

19. 4) Add any liquid ingredients if present.
5) Transfer mixture to a measuring cylinder & make the
volume.
6) Transfer to suitable container, cork it and label and
label with “Shake well before use “ direction.
MIXTURE CONTAINING INDIFFUSIBLE
SOLIDS

20. Rx
Chalk powder -----------30 grain
Catechu tincture ------------ 20 minim
Cinnamon water ------------ 1 fl.oz.
Direction: Secundis hora sumenda
Method of Preparation: Method of dispensing using
tragacanth powder
MIXTURE CONTAINING INDIFFUSIBLE
SOLIDS

21. DIFFUSIBLE AND INDIFFUSIBLE SOLIDS
INDIFFUSIBLE SOLIDS
1. In Diffusible solids are
insoluble substances which are
not evenly distributed in
vehicle for sufficient long time
on shaking .
2. Dose accuracy is less
3. Suspending agent is not
required
4. Substance does not penetrates
within solution
5. Substance does not float on
surface of water
6. Calamine , Zinc Oxide
DIFFUSIBLE SOLIDS
1. Diffusible solids are insoluble
substances which are light in
weight and are uniformly
dispersed in the vehicle on
shaking.
2. Dose accuracy is more
3. Suspending agent is not
required
4. Substance penetrates within
solution
5. Substance does not float on
surface of water
6. Calcium carbonate, Kaolin

22. These liquids are not only insoluble in water but they
form indiffusible precipitates particularly when salts are
present.
They contain resinous matter and when it is mixed with
water it leads to precipitation of resin and may stick to
the sides of the bottle which will be difficult to rediffuse
by shaking.
To prevent this, a protective colloid is dispersed in the
vehicle before tincture is added.
MIXTURE CONTAINING PRECIPITATE
FORMING LIQUIDS

23. A) Using compound tragacanth powder:
1. Finely powder the indiffusible solid and diffusible solid in the
mortar. Mix them with compound tragacanth powder in a mortar.
2. Measure half of the vehicle and incorporate a small amount of it to
the powders with trituration until a smooth cream is formed.
3. Then add the remaining part of the vehicle. Measure the precipitate
forming liquid in a dry measure and add it in a slow stream in the
centre of the cream with rapid stirring.
MIXTURE CONTAINING PRECIPITATE
FORMING LIQUIDS

24. 4. Dissolve the soluble ingredient (if present) in sufficient amount of
vehicle out of the remaining half of the vehicle.
5. Add it slowly with constant stirring to the cream to avoid local high
concentrations that may neutralize the effect of suspending agent.
6. Examine the contents of the mortar for foreign particles. If these are
present, strain the suspension through muslin piece into a bottle.
MIXTURE CONTAINING PRECIPITATE
FORMING LIQUIDS

25. 7. Add any liquid ingredients if present.
8. Transfer mixture to a measuring cylinder & make the volume.
9. Transfer to suitable container, cork it and label and label with
“Shake well before use “ direction.
MIXTURE CONTAINING PRECIPITATE
FORMING LIQUIDS

26. Rx
Potassium iodide 2.0ml
Tincture lobelia ether 4.0 ml
Tincture stramonium 16.0 ml
Chloroform water add up to 90.0 ml
DIRECTION: One dessertspoonful to be taken four times a day.
METHOD OF DISPENSING: Using Precipitate forming mixture
method
MIXTURE CONTAINING PRECIPITATE
FORMING LIQUIDS

27. The insoluble portion of slightly soluble liquids is not
readily diffusible.
So a suspending agent such as tragacanth powder or
tragacanth mucilage are needed to dispense such
mixtures.
Ex. Paraldehyde liquid
MIXTURE CONTAINING SLIGHTLY
SOLUBLE LIQUIDS

28. Rx
Paraldehyde 4.0 ml
Syrup 8.0 ml
Liquid extract of glycerrhiza 2.0 ml
Water add up to 30.0 ml
Direction: Take as directed.
MIXTURE CONTAINING PRECIPITATE
FORMING LIQUIDS

29. Vehicles:
Water: purified water
Aromatic water: Multiple use, e.g. chloroform water,
Cinnamon water, etc.
Medicated vehicle: Infusions, ex. Senegal infusion as
expectorant.
FORMULATION OF MIXTURE

30. Adjuncts: Adjuncts are used to improve the Safety,
efficacy and palatability.
Chemical Stabilizers: e.g. Antioxidant: Ascorbic acid
(0.1%), Sodium metabisulphite (0.1%) etc.
Preservatives: Chloroform (0.25%), Benzoic acid (0.1%)
Methyl paraben, Propyl paraben, etc.
Colouring Agents: E.g. Coal tar dyes.
FORMULATION OF MIXTURE

31. Sweeteners: sodium saccharin, sucrose, syrups etc.
Flavouring Agents: The following flavouring agents are
commonly used in mixtures.
a. Aromatic water
b. Syrup and Glycerol.
c. Spirit lemon to cover the taste of alkaline citrates.
d. Orange syrup and compound orange spirit.
FORMULATION OF MIXTURE

32.  Mixtures are dispensed in plain glass bottles with
uniform internal diameter.
 The mixture should be dispensed and supplied to the
patient for not more than 3 days to prevent deterioration.
 The bottle should be fitted with a suitable cork which
ensures its easy removal and to prevent spilling of
Mixture.
STORAGE OF MIXTURES