1. DRUG RELEASE PROFILE IN CDDS
2. Drug release profile graph
3. CLASSIFICATION OF CONTROLLED RELEASE SYSTEMS
4. DIFFERENCES BETWEEN MATRIX & RESERVOIR SYSTEM
5. RETARDANTS USED IN MATRIX TABLET FORMULATION
6. CLASSIFICATION OF NOVEL DRUG DELIVERY SYSTEMS
7. FORMULATION OF TRANSDERMAL DRUG DELIVERY SYSTEMS
8. CLINICALLY APPROVED LIPOSOMAL FORMULATIONS
2. DRUG
RELEASE
PROFILE IN
CDDS
ZERO ORDER
RELEASE
The delivery rate remains
constant until the device is
exhausted of the active agent
FIRST ORDER
RELEASE
The release rate is directly
proportion to the amount of
active ingredient loaded in the
device
SQUARE
ROOT OF
TIME
RELEASE
Release of drug is linear with the
reciprocal of the square root of
times. Release rate remains finite
even after the device approaches
exhaustion
5. CLASSIFICATION OF CONTROLLED RELEASE
SYSTEMS
CONTOLLED RELEASE SYSTEMS EXAMPLES
Diffusion controlled systems Matrix systems, reservoir systems
Dissolution controlled systems Matrix systems, reservoir systems
Water penetration controlled systems Swelling controlled systems, osmotically
regulated systems
Chemically controlled water systems Biodegradable/ bio-erodible system, ion
exchange resins, pendant systems
Regulated systems Magnetic, ultrasound, chemical release
systems
6. DIFFERENCES BETWEEN MATRIX &
RESERVOIR SYSTEM
MATRIX SYSTEM RESERVOIR SYSTEM
Achievement of zero order is difficult Achievement of zero order is easy
Suitable for both degradable & non- degradable
systems
Degradable reservoir systems may be difficult to
design
No danger of dose dumping Rupture can cause high risk of dose dumping
Not all drugs can be blended with a given
polymeric matrix
Drug inactivation by contact with the polymeric
matrix can be avoided
Can deliver high molecular wt. components Difficult to deliver high molecular wt.
components
8. CLASSIFICATION OF NOVEL DRUG DELIVERY
SYSTEMS
DRUG DELIVERY
SYSTEM
DEFINITION
LIPOSOMES Liposomes are small vesicles in bilayer form composed of phospholipids
(phosphatidylcholine) but may also include other lipids like egg
phosphatidylethanolamine, as long as they are compatible with lipid bilayer structure.
NIOSOMES They are a promising vehicle for drug delivery & being non-ionic. Have a better stability
than liposome & have physical properties similar to liposomes
NANOPARTICLES They are defined as particulate dispersion or solid nanoparticles of the size 10-1000nm.
Nanoparticles are used to target drugs to spleen & tumor cells also by I.V. route.
MICROSPHERES/
MICROPARTICLES
They are small spherical particles with diameters in the micrometer range (typical 1um to
1000um or 1mm). Drugs are dispersed in polymeric matrix
TRANSDERMAL DRUG
DELIVERY SYSTEMS
These are formulations that are applied to the body surface & are designed to deliver the
active drugs across the skin, into the systemic circulation.
9. CLASSIFICATION OF NOVEL DRUG DELIVERY SYSTEMS
contd...
DRUG
DELIVERY
SYSTEMS
DESCRIPTION
RESEALED
ERYTHROCYTES
Prepared by dipping RBCs in hypotonic media which leads to rupturing of cell membrane & formation
of small pores. When RBCs are again placed in an isotonic membrane @ 37C resealing of membrane
takes place with the drugs.
DENDRIMERS It is typically symmetric around the core and often adopts a spherical 3D morphology
ZYDIS SYSTEMS Drug dissolved/ suspended in an aq. Matrix is filled into preformed cavities in a blister pack, after that
the solution is frozen and water is removed by lyophilization mechanism
ANTIBODY
TARGETED
SYSTEMS
It consists of either a drug molecule linked covalently to the antibody/ vesicles (liposomes) containing
drug attached to antibody. Monoclonal antibody species for antigen or tumor cells can be used for
targeting of cytotoxic drugs
IONOPHORETIC
SYSTEM
In this a small electrical charge facilitates & controls drug movement from the anode to the cathode
and also through the biological membrane
10. FORMULATION OF TRANSDERMAL DRUG DELIVERY SYSTEMS
FORMULATION FUNCTION
Backing films Protects the active layer & safeguard the stability of the system. It is applied
to affect skin permeation & tolerance, depending on occlusion/
breathability
Release liners Used to protect the system as long as it is in the package. It also plays a
crucial role in the stability of the product
Pressure sensitive
adhesives
It has a critical effect on the stability of the system. Role is to release the
API and accurate administration of the drug
Active ingredients The drug should have M.W. < 1000 Da, it should have or affinity for both
lipophilic & hydrophilic phases, drug should have low M.P.
Permeation enhancers Increase the penetrability of the formulation by 3 mechanisms- LIPID
ACTION, PROTEIN MODIFICATION & PARTITIONING PROMOTION
Microporous Limit the flow of the semisolid content from the liquid reservoir, and to act
as a rate limiting membrane.
Pouching materials Increases the stability & integrity of the product
11. CLINICALLY APPROVED
LIPOSOMAL FORMULATIONS
ACTIVE INGREDIENT TRADE NAME
Amphotericin B Ambisome, Ambelcet, Amphotec
Cytarabine DepoCyt
Daunorubicin DaunoXome
Doxorubicin Myocet, Doxil/ Caelex
Morphine DepoDur
Verteporfin Visudyne
Vincristine sulfate Marqibo
Epaxal Inactivated hepatitis A viral strain RG-SB