PLGA (POLY LACTIC CO GLYCOLIC ACID)

1. PHAMACEUTICAL TECHNOLOGY -II
DR. K. N. M. I. P. E. R
PRESENTED BY-
SHILPI BANERJI
B.PHARM. 3RD YEAR

2. PLGA [POLY (LACTIC-C0-GLYCOLIC) ACID]
INTRODUCTION
SYNONYMS
STRUCTURE
SYNTHESIS
PHYSICO-CHEMICAL PROPERTIES
HANDLING AND USE
STORAGE
APPLICATIONS
CONCLUSION AND FUTURE PROSPECTS

3. INTRODUCTION
• Bone tissue engineering is a research field with many clinical applications,
such as bone replacement in the case of orthopaedic defects, bone
neoplasia and tumours, pseudoarthrosis treatment, stabilization of spinal
segments, as well as in maxillofacial, craniofacial, orthopaedic,
reconstructive, trauma, and neck and head surgery.
• For healing diseased or damaged bone tissue, the strategy of designing
synthetic bone substitutes, called scaffolds, is a promising alternative to the
use of allografts, autografts, and xenografts.
• Scaffolds for bone repair should be based on biomaterials with adequate
properties, such as biocompatibility, bioactivity, osteoconduction,
osteoinduction, and biodegradation.
• The most commonly used biodegradable synthetic polymers for three-
dimensional (3D) scaffolds in tissue engineering are saturated poly(α-
hydroxy esters), including poly(lactic acid) (PLA) and poly(glycolic acid)
(PGA), as well as poly(lactic-co-glycolide) (PLGA) copolymers

4. SYNONYMS
•Poly(D,L-lactide-co-glycolide)
•PLGA
•[POLY (LACTIC-C0-GLYCOLIC) ACID]

5. STRUCTURE

6. SYNTHESIS

7. PHYSICOCHEMICAL CHARACTERISTICS
• PLGA can be dissolved by a wide range of solvents,
depending on composition.
• Higher lactide polymers can be dissolved
using chlorinated solvents.
• PLGA degrades by hydrolysis of its ester linkages in the
presence of water.
• It has been proved that the time required for
degradation of PLGA is related to the monomers' ratio
used in production.
• the higher the content of glycolide units, the lower the
time required for degradation as compared to
predominantly lactide materials

8. Cont…
• PLGA has been successful as a biodegradable
polymer because it undergoes hydrolysis in
the body to produce the original monomers,
lactic acid and glycolic acid.
• These two monomers under normal
physiological conditions, are by-products of
various metabolic pathways in the body.
• Since the body effectively deals with the two
monomers, there is minimal
systemic toxicity associated with using PLGA
for drug delivery or biomaterial applications

9. HANDLING AND USE
• PLGA microspheres are inherently hydrophobic, and a small
amount of surfactant and / or a few seconds in an ultrasonic
bath may aid in suspending microspheres in aqueous media.
• Though actual biodegradation kinetics will be dependent on
the specific environment, e.g. pH, temperature, etc., spheres
are expected to fully biodegrade over a period of ~2-4
months in aqueous systems due to the hydrolysis of PLGA
ester linkages.
• Biodegradation is associated with loss in MW and mass, as
well as morphological alternations including surface erosion
and changes in geometry.
• PLGA polymers will dissolve in a variety of organic solvents,
e.g. THF, chloroform, acetone, etc.

10. STORAGE
• Store at 4-8˚C. Protect from
moisture. Microspheres may be
handled under nitrogen or other
inert gas for best stability.
Microspheres may be frozen /
desiccated for long-term storage.

11. APPLICATIONS
• Lactide=glycolide homopolymers and
copolymers have been applied in the clinic
as sutures, fixation devices in bone surgery
(plates, screws, and pins), and drug
delivery systems
• Poly(glycolide) and glycoliderich poly(L-
lactide-co-glycolide) have good fiber-
forming properties and suitable (relatively
fast) degradation rate to be applied as
sutures.[3

12. CONT…
• The use of PLGA in bone surgery offers
significant advantages.
• Self-reinforced, amorphous PLGA
copolymers of adequate mechanical
strength and appropriate rate of in vivo
degradation have recently been
developed as osteofixation materials in
craniofacial surgery

13. CONT…
• Amorphous PLGA polymers have received
wide attention as excipients in controlled
drug delivery systems and as antigen
carriers in the development of novel
vaccines.
• Tissue engineering can be used to restore,
maintain, or enhance tissues and organs.
Poly(lactide-co-glycolide) porous scaffolds
have been proposed as threedimensional
templates to guide tissue regeneration

14. CONCLUSION AND FUTURE PROSPECTS
• This Presentation reviews the potential of PLGA to favour bone tissue engineering,
due to its biological safety and tuneable degradation properties.
• As reported in this review, PLGA is categorized to its application forms: scaffolds,
fibres, hydrogels or microspheres; composite constructs based on PLGA and
hydroxyapatite are widely discussed.
• As reported, the addition of HA enhanced the osteoconductivity and the
mechanical properties of PLGA scaffolds for their use as load-bearing applications,
and the bone tissue regeneration.
• Finally, the review reports an alternative strategy to increase cell affinity or to
generate a biomimetic interface between PLGA and the biological environment,
involving the formation of the biomimetic apatite layer on the PLGA surface by
surface modification.
• Furthermore, the combination of both strategy (HA addition and surface
functionalization) in PLGA scaffold is expected to create an osteoconductive and
osteoinductive gradient, allowing an increased success of bone tissue regeneration.

15. THANK YOU