introductation, needs .concept, advantages and disadvantages components of tdds carriers biological events

1. TA R G E T E D D R U G
D E L I V E R Y S Y S T E M
P R E S E N T E D B Y
S U J I T H A M A R Y
M P H A R M
S T J O S E P H C O L L E G E O F P H A R M A C Y
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2. CONTENTS
• INTRODUCTION
• OBJECTIVE & NEEDS OF TDDS
• CONCEPT
• IDEAL CHARACTERISTICS
• ADVANTAGE & DISADVANTAGE
• COMPONENTS OF TDDS
• CARRIERS
• BIOLOGICAL PROCESS & EVENTS INVOLVED IN DRUG
TARGETING
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3. INTRODUCTION
• Targeted drug delivery system is a special form of drug delivery
system where the pharmacologically active agent or medicament is
selectively targeted or delivered only to its site of action or absorption
and not to the non-target organs or tissues or cells.
• Targeted drug delivery implies for selective and effective localization
of pharmacologically active moiety at pre identified (preselected)
target in therapeutic concentration, while restricting its access to non-
target normal cellular linings, thus minimizing toxic effects and
maximizing therapeutic index.
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4. OBJECTIVE :
• To achieve a desired pharmacological response at a selected sites
without undesirable interaction at other sites, there by the drug have a
specific action with minimum side effects & better therapeutic index.
• Ex- In cancer chemotherapy and enzyme replacement therapy.
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6. CONCEPT OF DRUG TARGETING
• The concept of designing targeted drug delivery system (TDDS) was
first given by Paul Ehrlich in 1902.
• He proposed the drug delivery to be a “magic bullet” and described
TDDS as an event, where a drug –carrier complex delivers a drug
exclusively to the preselected target cells in a specified manner.
• “Targeted drug delivery implies for selective and effective localization
of pharmacologically active moiety at preselected targets in
therapeutic concentration, while restricting its access to non-target
normal cellular linings, thus minimizing toxic effects and maximizing
therapeutic index”.
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7. IDEAL PROPERTIES OF TDDS
• It should be - Non-toxic, Biocompatible, Biodegradable
Physicochemical stable both in-vivo & in-vitro
• Controlled and predictable drug release
• Minimal drug leakage
• Carrier should be readily eliminated without causing any change in
diseased state
• Preparation should be easy, reproductive and cost effective
• Drug release should not effect drug action
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11. CARRIER SYSTEMS USED FOR
TARGETED DRUG DELIVERY
• Colloidal Carrier
* Vesicular system
* Microparticulate system
• Cellular carrier
• Supramolecular delivery system
• Polymer based delivery
• Macromolecular carrier
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13. TARGETING METHODS
• Antibodies
• Lectins and other proteins
• Lipoproteins
• Hormones
• Charged molecules
• Polysaccharides
• Low-molecular –weight ligand
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14. BIOLOGICAL PROCESS & EVENTS INVOLVED IN
DRUG TARGETING
1) Cellular uptake & Processing :-
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15. • Targeted drug delivery usually have macro molecular assemblies
hence cannot enter by such simple process. Hence take up by a
process called ENDOCYTOSIS.
• Steps involved :
Internalization of the plasma membrane
Concomitant with engulfment of extracellular material.
• Pinocytosis is divided into two types:
Fluid phases pinocytosis
Adsorptive pinocytosis
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16. 2) Transport across the epithelial barrier :-
• Depending on the position and function in the body epithelial cells
can be varied forms. Three layer physiology: Epithelial ,Lamia
propria ,Basal lamina.
• The polar materials diffuse through tight junctions of epithelial cells.
• Eg;-vaginal cavity could be an effective delivery site for certain
pharmaceuticals. Such as calcitonin for the treatment of
postmenopausal osteoporosis
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17. 3) Extravasation :-
Many diseases result from the dysfunction of cells
located outside the cardiovascular system thus for a drug to exert its
therapeutic effects it must exit from the central circulation this process
of trans vascular exchange is called Extravasation which is governed
by blood capillary walls.
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18. Depending on the morphology and continuity of the
endothelial layer and the basement membrane blood capillaries are
divided into :-
• Continuous -Continuous capillaries are common and widely
distributed in the body exhibit tight inter endothelial junctions and an
uninterrupted basement membrane.
• Fenestrated- Fenestrated capillaries shows inter endothelial gaps of
20-80nm.
• Sinusoidal- Sinusoidal capillaries show inter endothelial
gaps of 150nm.
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19. 3)LYMPHATIC UPTAKE
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20. CONCLUSION
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21. REFERENCE
• Gupta Manish & Sharma Vimukta, Targeted drug delivery system, A
Review, Research Journal of Chemical Sciences Vol-1 (2) page no:-
135-138, May 2011.
• Drug Targeting Organ-Specific Strategies Edited by Grietje Molema
and Dirk K. F. Meijer, page no:1-16.
• Targeted and Controlled drug delivery (Novel carrier systems), S P
Vyas and R K Khar, CBS publishers, page no: 38-61.
• http://slideshare.net.in
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