1. INTRODUCTION
Controlled release dosage form are designed to release drug in-vivo
according to predictable rate that can be verified by in-vitro measurement
Potential development and new approaches to oral controlled release dosage
form includes,
1. Hydrodynamic pressure controlled system
2. Intragastric floating tablet
3. Transmucosal tablet
4. Microporous membrane coated tablet.
Plasma
Concentration
Time
Osmotic drug delivery has come a long way since Australian physiologists
Rose and Nelson developed an implantable pump in 1955. Osmotic drug delivery uses
the osmotic pressure for controlled delivery of drugs by using osmogens (for upto 10 –
16 hrs).
A) WHAT IS OSMOTIC PRESSURE
Osmotic pressure is a most important colligative property according to
pharma point of view. Colligative property is the concentration of solution independent
of solute property.
Osmotic pressure of a solution is the external pressure that must be applied
to the solution in order to prevent it being diluted by the entry of solvent via a process
known as Osmosis.
Such membrane is only permeable to solvent molecule. Because only solvent
can pass through the semi permeable membrane, the driving force for the osmosis arises
from the inequity of the chemical potentials of the solvent on opposing side of the
membrane.
PHARM AQUEST
,B) WHERE IT IS USE IN PHARMA
For adjustment For developing Osmotic For Oral use inof
tonicity in drug delivery system treatment of
Parentral Constipation
Ophthalmic Hypertension
2. DEFINITION
Osmolality is the number of osmoles per Kg of water.
Osmolarity is the number of osmoles per liter of solution.
Iso-osmotic solution is one where two solution are separated by a perfect
semi permeable membrane (SPM is membrane which is permeable only to solvent
molecule and no net movement of solute occur across the membrane.
In Isotonic solution biological membrane do not always function as perfect
SPM and some solute molecule as well as water are able to pass through them.
3. ADVANTAGE OF OSMOTIC DDS
PHARM AQUEST
, 4. DISADVANTAGE OF OSMOTIC DDS
Osmotic system
5. NEED FOR DEVELOPING DOSAGE FORM
1. In order to reduce the dose
2. To decreases dose related side effect
3. To minimizes rate of administration
4. To provide controlled release and
5. To increase patient compliance.
6. MECHANISM OF OSMOSIS
Core contain water soluble osmotically active agent and blended with water
soluble or insoluble drug, additives and coating has been carried out which functions as
semi permeable membrane.
Since barrier is only permeable to water, initial penetration of water dissolves
the critical part of the core, resulting in development of an osmotic pressure difference
across the membrane.
PHARM AQUEST
Controlled release dosage form are designed to release drug in-vivo
according to predictable rate that can be verified by in-vitro measurement
Potential development and new approaches to oral controlled release dosage
form includes,
1. Hydrodynamic pressure controlled system
2. Intragastric floating tablet
3. Transmucosal tablet
4. Microporous membrane coated tablet.
Plasma
Concentration
Time
Osmotic drug delivery has come a long way since Australian physiologists
Rose and Nelson developed an implantable pump in 1955. Osmotic drug delivery uses
the osmotic pressure for controlled delivery of drugs by using osmogens (for upto 10 –
16 hrs).
A) WHAT IS OSMOTIC PRESSURE
Osmotic pressure is a most important colligative property according to
pharma point of view. Colligative property is the concentration of solution independent
of solute property.
Osmotic pressure of a solution is the external pressure that must be applied
to the solution in order to prevent it being diluted by the entry of solvent via a process
known as Osmosis.
Such membrane is only permeable to solvent molecule. Because only solvent
can pass through the semi permeable membrane, the driving force for the osmosis arises
from the inequity of the chemical potentials of the solvent on opposing side of the
membrane.
PHARM AQUEST
,B) WHERE IT IS USE IN PHARMA
For adjustment For developing Osmotic For Oral use inof
tonicity in drug delivery system treatment of
Parentral Constipation
Ophthalmic Hypertension
2. DEFINITION
Osmolality is the number of osmoles per Kg of water.
Osmolarity is the number of osmoles per liter of solution.
Iso-osmotic solution is one where two solution are separated by a perfect
semi permeable membrane (SPM is membrane which is permeable only to solvent
molecule and no net movement of solute occur across the membrane.
In Isotonic solution biological membrane do not always function as perfect
SPM and some solute molecule as well as water are able to pass through them.
3. ADVANTAGE OF OSMOTIC DDS
PHARM AQUEST
, 4. DISADVANTAGE OF OSMOTIC DDS
Osmotic system
5. NEED FOR DEVELOPING DOSAGE FORM
1. In order to reduce the dose
2. To decreases dose related side effect
3. To minimizes rate of administration
4. To provide controlled release and
5. To increase patient compliance.
6. MECHANISM OF OSMOSIS
Core contain water soluble osmotically active agent and blended with water
soluble or insoluble drug, additives and coating has been carried out which functions as
semi permeable membrane.
Since barrier is only permeable to water, initial penetration of water dissolves
the critical part of the core, resulting in development of an osmotic pressure difference
across the membrane.
PHARM AQUEST
