K. Teja kumar Reddy
Chilkur balaji college Of Pharmacy,
A more recent technique, “powdered solution
technology” or “Liquisolid technology”, has
been applied to prepare water-insoluble drugs
into rapid-release solid dosage forms.
The term “ liquisolid compacts technique ”
refers to process of preparation of immediate or
sustained release tablets or capsules using the
“liquisolid systems” combined with the
inclusion of appropriate excipients required for
tabletting or encapsulation.
Nearly one-third of drugs in development are water
insoluble and one-half fail in trials because of under
The dissolution rate is the rate limiting factor in drug
absorption for class II (low solubility and high
permeability) and class IV (low solubility and low
permeability) drugs as defined in the
Biopharmaceutics Classification System.
More effective than Various techniques which have
been employed to enhance the dissolution profile and,
in turn, the absorption efficiency and bioavailability
of water insoluble drugs.
Micronization, adsorption on the high surface area
carriers, lyophilization, co-precipitation, micro-
encapsulation, solubilization by surfactants, solid
dispersions, solid solutions.
Micronization is the most common method to increase
the drug surface area.
But this becomes less effective when they are
formulated as tablets or encapsulations.
The most promising method for promoting dissolution
is the formation of liquisolid tablets.
A liquisolid system refers to formulations formed
by conversion of liquid drugs, drug suspensions or
drug solution in non-volatile solvents, into dry,
non-adherent, free flowing and compressible
powder mixtures by blending the suspension or
solution with selected carriers and coating
These techniques are carefully selected on the
basis of properties of drug, excipients and dosage
Liquid load factor (Lf)
Coating Material Ratio (R)
For poorly soluble, insoluble, liquid drugs or
lipophilic drug .
For poorly flowable powder admixtures.
To aid direct compression.
To improve efficiency of tablet manufacturing.
Large number of Bio-Pharmaceutical classification
class II and class IV.
Improvement of Bio-availability of an orally
administered water insoluble drugs is achieved.
Drug is formulated in a tablet form or encapsulated
dosage form and is held in solubilized liquid state,
which confers developed or improved drug wetting
pro-perties thereby improving drug dissolution
production cost is low as compared to soft gelatin
This liquisolid system is specifically for powdered liquid
Greater drug surface area is exposed to the dissolution
These Liquisolid systems formulate into immediate
release or sustained release dosage forms.
Capability of industrial production is also possible.
Optimized sustained release Liquisolid tablets or capsules
of water insoluble drugs demonstrate constant dissolution
rates (Zero Order Release).
Excellent flowability and compressibility.
Drug release can be modified using suitable formulation
Liquisolid technology as described by “Spireas” a
liquid may be transformed into a free flowing, readily
compressible and apparently dry powder by simple
physical blending with selected excipients named the
carrier and coating material.
The liquid portion, which can be a liquid drug, a drug
suspension or a drug solution in suitable non-volatile
liquid vehicles is incorporated into the porous carrier
Schematic representation of liquisolid systems.
A. Based on the type of liquid medication contained.
1. Powdered drug solutions.
2. Powdered drug suspensions.
3. Powdered liquid drugs.
B. Based on the formulation technique used.
1. Liquisolid compacts.
2. Liquisolid Microsystems.
A. Increased drug surface area
B. Increased aqueous solubility of the drug
C. Improved wetting properties
1. Determination solubility of drug in different non-
2. Determination of angle of repose.
3. Determination of flowable liquid retention
potential (Φ value).
4. Calculation of liquid load factor (Lf).
5. Liquisolid compressibility test.
Solubility and dissolution enhancement.
Used efficiently for water insoluble solid drug
or liquid lipophilic drug.
Rapid release rates.
Designed for control release tablet.
Designed for sustained release of water soluble
drug such as propranolol hydrochloride.
Application in probiotics.
The Liquisolid technique is a promising alternative to
enhance the absorption as well as dissolution rate their by
it may enhance the bio-availability of a poorly soluble,
liquid drugs, insoluble or lipophilic drugs.
Liquisolid tablets prepared were found in terms of faster
disintegration time, dissolution profile, acceptable tablet
properties and stability.
The technique is also used to design immediate release or
sustained release systems.
Therefore, this technique has the potential as safer and
efficacious method, hence should considered to be
manufactured on a large scale.
1. Spiras S., Bolton S., “Liquisolid systems and methods
for preparing same”,(2000), United States patent:
2. Shashidher B., Madhusudhanrao Y., “The Liquisolid
Technique: An Overview”, Brazilian Journal of
Pharmaceutical Sciences, vol-47, (2011), p. n. 3.
3. Gavali S. M., Pacharane S. S., Sankpal S. V.,
“Liquisolid Compact: A New Technique for
Enhancement of Drug Dissolution”, IJRPC, (2011),
Department of Pharmaceutics, p.n. 705-710.
4. Dr. Leopold C. S., Dr. Geffken D., “Optimization of the
Liquisolid Technology”, (2011), p.n. 2-27.