Gels and jellies are semisolid dosage forms used to deliver drugs. Gels contain a gelling agent that is dispersed in water, producing a jelly-like consistency. Common gelling agents include polymers, natural gums, and cellulose derivatives. Gels are classified as single-phase or two-phase based on distribution of the gelling agent. Jellies are transparent and less greasy than gels. Common gelling agents for jellies include tragacanth, sodium alginate, pectin, and gelatin. Key evaluation tests for gels and jellies include pH, drug content, viscosity, and spreadability.

1. Mr.Ravikumar R Patil
Dr.Shivajirao Kadam College of Pharmacy
Kasabe digraj, Sangli

2. INTRODUCTION
GELS
 Gels are semisolid dosage form.
 In that dispersion of small or large molecules in an aqueous liquid
vehicle.
 They produce jelly like consistency by the addition of a gelling agent.
 Gels are formed by using synthetic polymers such as carbomer 934 &
cellulose such as hydroxypropylcellulose &
hdroxypropylmethylcellulose.
 Tragacnth, pectin, agar natural gums are used in the formulation of gels.

3.  As per NF, six polymers are used for gel formulation.
Those are followings,
 Carbomers 910
 Carbomer 934
 Carbomer 934P
 Carbomer 940
 Carbomer 941
And
 Carbomer 1342
 Carbomer 940 produce highest viscosity betw.
40,000 & 60,000 centipoises in 0.5% aq. Solution.

4.  Gels may thicken on standing, forming a thixotrope and
must be shaken before use to liquefy the gel.
 In the gel contains drug substance with water.
 Also contain solvents such as, alcohol or propylene glycol.
 Antimicrobial preservatives used in gel formulation such
as, methylparaben, propylparaben etc.
 It also contains stabilizers e.g. edetate disodium (EDTA).
 Medicated gels prepared for administration by various
routes for eye, nose, vaginal & rectum.

5. CLASSIFICATION OF GELS
 Single- phase gel
 Two- phase gel
 In single phase gel contains macromolecules are uniformly
distribute throughout the liquid with no apparent
boundaries betw. macromolecules & the liquid.
 In two phase gel contains small separate particles also
called as magma.
 E.g. Milk of magnesia (Magnesia magma) in that
gelatinous precipitate of magnesium hydroxide.

6. TYPES OF GELS
HYDROGELS
XEROGELS
ORGANOGELS

7. HYDROGELS
 A hydrogel is a network of polymer chains that are
hydrophilic, sometimes found as a colloidal gel in which
water is the dispersion medium.
 Hydrogels are highly absorbent(they can contain over
90% water) natural or synthetic polymeric networks.
 Hydrogels also possess a degree of flexibility very similar
to natural tissue, due to their significant water content.
 Common ingredients include polyvinyl alcohol, sodium
polyacrylate, acrylate polymers and copolymers with an
abundance of hydrophilic groups.

8. Uses:
 As scaffolds in tissue engineering.
As environment sensitivity detector.
Sustained release DDS.
Contact lenses.
ECG medical electrode.
Glue

9. XEROGELS
 Open network formed by the removal of all swelling
agents from a gel.
 Xerogels usually retain high porosity (15–50%) and
enormous surface area (150–900 m2/g), along with very
small pore size (1–10 nm).
 When solvent removal occurs under supercritical
conditions, the network does not shrink and a highly
porous, low-density material known as an aerogel is
produced.

10. Uses:
 IN DDS

11. ORGANOGELS
 An organogel is a non-crystalline, non-glassy thermo
reversible (thermoplastic) solid material composed of a
liquid organic phase entrapped in a three-dimensionally
cross-linked network.
 The liquid can be, for example, an organic solvent, mineral
oil, or vegetable oil.
 These systems are based on self-assembly of the structuring
molecules.

12. Uses:
In pharmacy used as drug carrier for TDDS.
In cosmetics for application & stability and
food industry.

13. Commonly Used Gelling Agents
 Acacia
 Pectin
 Starch
 Tragacanth
 Xanthan gum
 Alginic acid (seaweed)
 Animal/vegatable fats: cocoa butter
 Gelatin
 Bentonite, veegum (magnesium aluminum silicate)
 Carboxymethylcellulose (CMC) and other cellulose
derivatives
 Carbomer resins (Carbopols)
 Colloidal silicon dioxide
 Polyvinyl alcohol (PVA)
 Petrolatum, mineral oil/polyethylene gel.

14. Method of Formulation
There are 3 methods:
Fusion Method
Cold Method
Dispersion Method

15. Fusion Method
 In this method various waxy materials employed
as gellant in non polar media.
 Drug was added when waxy materials melted by
fusion.
 stirred slowly until uniform gel formed.

16. Cold Method
 Water was cooled to 4-100c and placed it in
mixing container.
 Gelling agent was slowly added and agitating
until solution is complete.
 Maintained temperature below 100c .
 Drug was added in solution form slowly with
gentle mixing.
 Immediately transfer to container & allow to
warm to R.T where upon liquid becomes clear
gel.

17. Dispersion Method
 Gelling agent was dispersed in water with stirring
at 1200 rpm for 30 min .
 Drug was dissolved in non-aqueous solvent with
preservative.
 This solution was added in above gel with
continuous stirring.

18. JELLIES
INTRODUCTION
 Jellies are transparent or translucent non-greasy
semisolid dosage form.
 They are less greasy compare gel.
 They are mainly used for mucous membrane for
lubricating, antiseptic purpose.
 Jellies are also used for lubricating surgical gloves,
catheters & rectal thermometers.
 Vaginal jellies & contraceptive jellies are also commonly
used.

19.  Medicated jellies contains a considerable amount of water
therefore those are suitable for water soluble medicaments.
 Such as, anaesthetics, antiseptics and spermicides.
 They are unsuitable for insoluble medicaments.
 They are easy to apply.
 After evaporation of water they produce cooling sensation to the
skin.
 When treatment is over, they can be easily removed by washing
with water.

20. Preparation of Jellies
 Pharmaceutical jellies are usually prepared by adding a
thickening agents.
 Such as tragacanth or carboxymethyl cellulose.
 Thickening agents is transferred into aqueous solution in
which drug has been dissolved.
 The mass is triturated in mortar until a uniform product
is obtained.

21. Following jelling agents are used…
 Tragacanth
 Sodium alginate
 Pectin
 Starch
 Gelatin
 Cellulose derivatives

22. Tragacanth
 It is commonly used for the
preparation of lubricating,
medicated & contraceptive jellies.
 For lubricating jellies 2 to 3 %
 For dermatological vehicle about 5%
 For medicated jellies 5%

23. Cont…
 Tragacanth jellies are also called bassorin
paste.
 When tragacanth added in water it
produce lumpy product.
 So, dispersing agents like alcohol,
glycerin or a volatile oil is used to get a
homogeneous preparation.

24. Sodium Alginate
 Those jellies are used as lubricants &
for dermatological vehicles.
 In lubricants 1.5 to 2% & for
dermatological vehicle 5 to 10%
sodium alginate used.
 In that type of jellies alcohol,
propylene glycol or glycerin used as
dispersing agents.

25. Pectin
 Pectin is a very good gelling agent.
 Pectin used in various preparation of jellies including
edible jellies.
 It is mainly used in dermatological jellies.
 Glycerin is used as humectant & dispersing agent.
 Pectin jellies prepared with suitable preservatives.

26. Starch
 Starch jellies prepared with combination of gelatin &
glycerin.
 Starch glycerin jellies prepared by heating method or
fusion method.
 Glycerin in large amounts i.e 50% may be act as
preservative & humectant.

27. Gelatin
 Gelatin soluble in hot water.
 2% gelatin produce jelly in a hot solution.
 Very stiff medicated jellies can be prepared by
incorporating with 15% gelatin.
 Such jellies melted before use & after cooling to desired
temperature it can be applied with brush on affected area.
 Those applied areas are cover with bandage.
 The dressing may be left in place after several weeks.
 Zinc gelatin jellies is also known as Unna’s paste.

28. Cellulose derivatives
 Methyl cellulose & sodium carboxy methyl cellulose
are widely used for preparation of jellies.
 Those substances produce natural & stable jellies.
 Those afford good resistance against bacterial growth.
 Those produce strong film on the skin after drying on
skin.

29. Evaluation test for Gels & Jellies
 pH determination
 Drug content
 Viscosity
 Spreadability

30. Spreadability
S = M. L/M
M = wt. tied to upper slide
L = Length of glass slide
T = Time taken to separate the slides