Download Medical Application of Membrane in Drug Delivery Syestem

NUR HIDAYAH OMAR
SITI HAJAR ABU BAKAR
ALIA ZULAIKHA MOHD HANIF
INTRODUCTION
• Membrane technology is of major importance in
medical applications
• Used in drug delivery, artificial organs, tissue
regeneration, diagnostic devices, as coatings for
medical devices, bioseparations, etc.
• Delivery system is to deliver a drug to a specific
site, in specific time and release pattern.
Membrane –based system
• Membrane-based systems basically a drug
reservoir is contained in a membrane device.
Two types of systems can be distinguished:
• Osmotic membrane systems.
• Diffusion controlled membrane systems.
Osmotic Membrane System
• Consists of a reservoir made of a polymeric
membrane permeable to water but not to the
drug (semi-permeable membrane).
• The reservoir contains a concentrated drug
solution. As water crosses the membrane due
to osmotic pressure, the drug solution is
released through the orifice.
Diffusion Controlled Membrane
System
• The drug release is controlled by transport of
the drug across a membrane.
• The transport is dependent on the drug
diffusivity through the membrane and the
thickness of the membrane
• The membrane can be porous or non-porous
and biodegradable or not.
LIPOSOME
• An artificially-prepared vesicles
composed of a lipid bilayer.
• Used as a vehicle
for administration of
nutrients and pharmaceutical
drugs.
• Composed of
natural phospholipids, and
contain mixed lipid chains
with surfactant properties
• Liposomes vary in size due to
their medication type like DNA,
enzyme, drugs, and
supplementation .
Targeted delivery
• Liposomes prepared from natural or synthetic
phospholipids containing an encapsulated
drug. This type of drug delivery reduces
toxicity, maintains or enhances activity and
facilitates accumulation in the disease site.
• Conventional liposornes that incorporate
lipids enhancing circulation lifetimes. Delivery
in these molecules improves access to the
disease site and reduces interaction with
phagocytic cells of the reticulo-endothelial
system.
• Conventional liposomes with lipids that enhance
circulation lifetimes and have
surface-associated targeting information. Drug
delivery using this type of liposome results in an
improved therapeutic index and target cell
specific delivery.
• Examples; antibodies (glycolipids and mannose),
proteins (e.g. Transferrin and asialofetuin) , and
vitamins (e.g. folic acid have been used to target
specific cells via cell surface receptors
• Fusogenic liposomes with DOPE or fusogenic
proteins. This method allows intracellular drug
delivery.
•DOPE has been particularly useful for cationic
liposomes complexed with plasmid DNA for
gene delivery.
Applications of Membrane System
Pills
• The diffusion principle is applied to
pills and tablets.
• The drug is pressed into tablet which
is coated with a non-digestible
hydrophilic membrane.
• Once this membrane gets hydrated, a
viscous gel barrier is formed, through
which the drug slowly diffuses.
• The release rate of the drug is
determined by the type of membrane
used
Implants
• consist of a membrane reservoir containing a
drug in liquid or powder form
• The drug slowly diffuses through the semipermeable membrane and the rate of diffusion
depends on the characteristics of both the drug
and membrane.
• The thickness of the membrane is constant to
secure uniformity of drug delivery.
• If the membrane degrades, drug delivery should
be accomplished prior to membrane degradation.
• If the membrane is made of non-degradable
material, it should be surgically removed
afterwards.
• A drawback of implants is the risk of membrane
rupture resulting in drug-dumping: a sudden
release of large amounts of drugs
Patches
• Patches are broadly used in drug
delivery.
• The most characteristic examples are
ocular (eye) and transdermal patches.
• Ocular patches are typical membranecontrolled reservoir systems. The drug,
accompanied by carriers, is captured in a
thin layer between two transparent,
polymer membranes, which control the
rate of the drug release
• An annular white-coloured border is
surrounding the reservoir for handling of the
device.
• The device is placed on the eye, where it
floats on the tear film.
• Through diffusion, the drug is directly
administered to the target area.