biodegradable natural polymers (2)
TRANSCRIPT
BIODEGRADABLE NATURAL POLYMERS
Prepared by: (Group B)Ajay ShahBhaskar ShresthaEroj YemiManisha ShresthaPrakriya ShresthaRajiv DangolSajan MaharjanTripti Amatya
S.No
Topics Name Date
1 Introduction Tripti Amatya
19th to 21nd January 2014
2Gelatin
Manisha Shrestha
3 Prakriya Shrestha
4Chitosan
Bhaskar Shrestha
5 Eroj Yemi
6Hyaluronic Acid
Rajiv Dangol
7 Sajan Maharjan
8Conclusion & Compilation
Ajay Shah
Log Book
Discussion on Topic: Tuesday; 14 January, 2014Internet Survey: Wednesday to Friday; 15 to 17 January, 2014Work Division: Saturday; 18 January, 2014
Disscussion and Modification of Assignment: Wednesday to Saturday; 22 to 25 January, 2014Preparation of Presentation: Friday to Sunday; 24-26th January, 2014
INTRODUCTION
Polymer Definition
Also known as macro-molecules.
Biodegradation Biodegradation is the process of converting polymer material into harmless, simple, gaseous products by the action of enzymes, micro-organisms and water.
Biodegradable Polymer Biodegradable polymers degrade as a result of natural biological processes, eliminating the need to create a disposal system which can cause harm to our environment.
BIODEGRADATION
ENZYMATIC DEGRADATION
COMBINATIONHYDROLYSIS
BULK EROSION SURFACE EROSION
Mechanism Of Biodegradable Polymers
ENZYMATIC DEGRADATION
Need for Biodegradable polymer
Do not require a second surgery for removal Avoid stress shielding Offer tremendous potential as the basis for
controlled drug delivery
BONE+PLATE
BONE PLATE
Time
Mec
han
ical
Str
engt
h
Degradable Polymer Plate
NATURAL POLYMERSThese are the polymers obtained from natural
resources, and are generally non-toxic.Natural polymers are formed in nature during the
growth cycles of all organisms.NATURAL POLYMERS
PROTEINS Polysaccharides
Eg: COLLAGEN ALBUMIN FIBRIN
Eg : DEXTRAN CHITOSAN STARCH
ADVANTAGES : 1) Readily & Abundantly Available.2) Comparatively Inexpensive.3) Non toxic products.4) Can be modified to get semi synthetic
forms.
Classification of Natural biodegradable polymers(Based on Origin)
Plant Animal Microbes
PolysaccharidesEg: Cellulose, Starch, Alginate
ProteinsEg: Collagen (Gelatin), Albumin
PolysaccharidesEg: Chitin (Chitosan), Hyaluronate
PolyestersEg: Poly(3-hydroxylalkonate)
PolysaccharidesEg: Hyaluronate
CHITOSAN: INTRODUCTION
Chitin is a macromolecule found in the shells of crabs, lobsters, shrimps and insects
Chitosan is obtained by partial deacetylation of chitin.
Chitin is insoluble in its native form but chitosan, the partly deacetylated form, is water soluble.
CHEMISTRY
linear co-polymer of β(1-4) linked glucosamine and N-acetyl-D-glucosamine.
EXTRACTION OF CHITOSAN
Crustacean shells(containing chitin)
De colorization
Dil. NaOH Dil. HCl
Deproteinization
Deacetylation(chitosan)
Demineralization
0.5% KMnO4 and oxalic acid
Hot Conc. NaOH (40-50%)
PHYSIOCHEMICAL PROPERTIES
Odorless, white or creamy-white powder Chelates many transitional metal ions Highly basic polysacharides in acidic pH, it gets solubilized due to protonation
of free amino groups and the resultant soluble polysaccharide is positively charged.
hydrophilic in nature thereby it has the ability to form gels at acidic pH.
Degraded by lysozyme to it’s by products glucosamine and n-acetyl glucosamine
APPLICATION
Ocular delivery: making contact lens- optical clarity, sufficient optical
correction, gas permeability, particularly towards oxygen, wettability and immunological compatibility.
antimicrobial and wound healing properties of chitosan along with an excellent film capability make chitosan suitable for development of ocular bandage lenses.
Colon drug delivery: Degraded by microflora present in human colon which
supports colon drug delivery
Coating material: Good film forming property and mucoadhesive property
Mucosal delivery: Chitosan gets protonated in acidic solution, so it
binds strongly to negatively charged cell surface making it useful to formulate bioadhesive dosage forms.
Transdermal drug delivery: Studies on propranolol hydrochloride (prop-HCl)
delivery systems using various chitosan membranes with different crosslink densities as drug release controlling membranes and chitosan gel as the drug reservoir have been performed.
Gene Delivery: Chitosans, typically isolated from the shell of
shrimp, has the ability to react with DNA and compact it to produce a nanoparticle. Such nanoparticles are more readily taken up by cells.
Others: nano band- aid,cosmetics, etc.
HYALURONIC ACID:INTRODUCTION
Carbohydrate polyanionic mucopolysacharide, occurring naturally in all living organisms.
Can be several thousands of sugar long One of most hydrophiic molecules, also
known as natural moisturizer Generally found in sodium salt form i.e.
as sodium hyaluronate
BIOSYNTHESIS OF HA IN BACILLUS SUBTILIS
UDP- glucoronic acid
HYALURONIC ACID
UDP-N-acetylglucosamine
Hyaluronan synthase
Pentose phosphate pathway Glycolysis
UDP
UDP
•HA is naturally synthesized from addition of glucoronic acid and N-acetylglucosamine to growing chain using their activated nucleotide sugars. Hyaluronan synthase is the enzyme responsible.
STRUCTURE AND CHEMISTRY
Polysaccharide made up of largely repeating disaccharide units
The alternating disaccharide units are linked by (1→4) inter glycosidic linkage.
Chains consist upto 30,000 repeating units so it has high molecular weight range (1000 to 10,000,000 Da).
PROPERTIES Biodegradable, biocompatible, non-toxic, non-
immunogenic, non-inflammatory, linear chain polysaccharide
very hydrophilic; it adsorbs water making it hygroscopic
readily soluble in water, and produces a gel Its viscous solutions have most unusual
rheological properties (pseudoplasticity) and are exceedingly lubricious
To improve the mechanical properties and control the degradation rate, HA can be chemically modified or crosslinked to form a hydrogel
of the gel is dependent upon a number of factors including the length of the chain, cross-linking, pH
APPLICATION
They are used in the preparation of gels for delivery of drugs to eye and installation into other cavities.
Microparticulate HA carrier: Sustained-release formulations (eg: protein drugs)
have been developed using spray-dried HA microparticles which act as a protein reservoir
Also protects the drugs from denaturation and increases their bioactivity
Ocular drug delivery: Its viscosity and pseudoplastic behavior which
provide mucoadhesive property can increase the ocular residence time
Cell targetting: The expression of CD-44 (cluster determinant
44) and RHAMM (receptor for hyaluronate-mediated motility) receptors by various tumour cells, which are endogenous ligands for HA, makes this a good candidate for drug targeting to cancer cells
Nasal delivery: A nanocarrier composed of hyaluronic acid(HA)
and chitosan(CH) was reported to encapsulate bovine serum albumin (BSA) and cyclosporine A for the nasal delivery of macromolecules
Topical drug delivery: Surface hydration and film formation enhance
the permeability of the skin to topical drugs also promotes drug retention and localization in the epidermis
HA has been used in tissue engineering for the cartilage replacement in the joints
Used in cosmetics, skin care system, as anti ageing therapy (antioxidant nature)
GELATIN-INTRODUCTION
• Gelatin is a natural water soluble functional polymer (protein) that is derived by partial hydrolysis of collagen (chief protein component in skin, bones and white connective tissues of the animal body).
• It is commonly used for pharmaceutical and medical applications because of its biodegradability and biocompatibility in physiological environments.
• Gelatin does not occur free in nature, and derived from chief protein component in skin, bones, hides, and white connective tissues of the animal body is classified as a derived protein
GELATIN-TYPES
Gelatin derived from an acid-treated precursor is known as Type A and gelatin derived from an alkali-treated process is known as Type B.
Results in a difference in isoelectric points, being 7 – 9 for gelatin type A and 4 – 5 for gelatin type B.
FEATURES OF GELATIN
Characteristic features of gelatin are the high content of the amino acids glycine, proline (mainly as hydroxyproline) and alanine.
Gelatin molecules contain repeating sequences of glycine, proline and alanine amino acid triplets, which are responsible for the triple helical structure of gelatin.
STRUCTURE OF GELATIN
The chemical structure of gelatin is what makes gelatin water soluble; form digestible gels and films that are strong, flexible, and transparent; and form a positive binding action that is useful in food processing,pharmaceuticals, photography,and paper production.
MFG OF GELATIN
PHYSICAL PROPERTIES
Tasteless and odorless Vitreous, brittle solid, yellow colored Moisture content: 8-13% ; Relative density of: 1.3-1.4 Formation of thermo-reversible gels in water: When
gelatin granules are soaked in cold water they hydrate into discrete, swollen particles. On being warmed, these swollen particles dissolve to form a solution.
CHEMICAL PROPERTIES
Soluble in aqueous solutions of polyhydric alcohols such as glycerol and propylene glycol.
Insoluble in less polar organic solvents such as benzene, acetone, primary alcohols and dimethylformamide.
Gelatin stored in air-tight containers at room temperature remains unchanged for long periods of time. When dry gelatin is heated above 45° C in air at relatively high humidity (above 60% RH) it gradually loses its ability to swell and dissolve.
Sterile solutions of gelatin when stored cold are stable indefinitely; but at elevated temperatures the solutions are susceptible to hydrolysis.
Gelatin is composed of 50.5% carbon, 6.8% hydrogen, 17% nitrogen and 25.2% oxygen. It gives typical protein reactions and is hydrolyzed by most proteolytic enzymes to yield its peptide or amino acid components.
APPLICATION OF GELATIN IN PHARMACEUTICAL FORMULATION AND DRUG DELIVERY Two-Piece Hard Capsules Soft Elastic Gelatin Capsules As a binder in Tablet Tablet Coating Suppositories Gelatin Emulsions Microencapsulation Source of essential amino acids Absorbable Gelatin Sponge Gelatin as Nanoparticle.
CONCLUSION
Biodegradable polymers have received much more attention in the last decades due their potential applications in the field of pharmaceuticals.
Biodegradable polymers have been researched, but polymers based on renewable sources (especially on starch) are most desirable.
It provides a drug at a constant controlled rate owes a prescribed period of time; cell targeting, colon targeting and nasal drug delivery system and also assist in gene therapy.
It would degrade into nontoxic, absorbable subunits which would be subsequently metabolized and removed from the body.
Recently different studies have been reported concerning the use of degradable polymers, especially with starch and aliphatic polyesters.
Reference Gelatin Manufacturers Institute of America Members as of January 2012,
Gelatin Handbook. Djagny B. K.,Wang Z. , Xu S. ,Gelatin: A Valuable Protein for Food and
Pharmaceutical Industries: Review,Critical Reviews in Food Science and Nutrition, 41(6):481–492 (2001).
Wiley J. & Sons, Encyclopedia of Polymer Science and Technology. Ward, A. G., Structure and Properties of Gelatin, Food, 1951; 20: 255. Ames, W. M., The Conversion of Collagen to Gelatin and their Molecular
Structures, J. Sci. Food Agric.,1952; 3: 454–463. R. T. Jones, in K. Ridgway, ed., Hard Capsules Development and
Technology, The Pharmaceutical Press, London, 1987, pp. 41–42. Remington’s Pharmaceutical Science, 1985. 17th edition, Mach
Publishing Company. The United States Pharmacopeia XXII (USP XXII–NFXVII), the United
States Pharmacopeial Convention, Inc., Rockville, Md., 1989. Dutta P.K., Dutta J., Tripathi V.S., Chitin and Chitosan: Chemistry,
properties and applications,Journal of Scientific and Industrial Research, Vol.63,January 2004, pp. 20-31.
Bansal V., Sharma S. K., Sharma N.,Pal O.P., Malviya R., Applications of Chitosan and Chitosan derivatives in Drug Delivery,Advances in Biological Research,Vol. 5(1),2011,pp. 28-37.
Majeti N.V., Kumar R., Review of Chitin and Chitosan applications, Reactive and Functional Polymers, Vol.46,2000,pp. 1-27.
Wade A., Weller P.J., Handbook of pharmaceutical excipients, fifth edition.J. Necas L. Bartosikova, P. Brauner, J. Kolar; Hyaluronic acid (hyaluronan): a review Veterinarni Medicina, 53, 2008 (8): 397–411 Menaa F, Menaa A, and Menaa B. Hyaluronic Acid and Derivatives for Tissue
Engineering J Biotechnol Biomaterial, 2011 Yu-Jin J, Ubonvan T and Dae-Duk K. Hyaluronic Acid in Drug Delivery Systems
Journal of Pharmaceutical Investigation Vol. 40, No. Special issue, 33-43 (2010) Sodium hyaluronate, Handbook of Pharmaceutical Excipients; Pharmaceutical
Press. 6th edition pg. 647 Veeran G.K and Betageri G.V. Water Soluble Polymers for Pharmaceutical
Applications, Polymers 2011, 3, 1972-2009; doi:10.3390/polym3041972 Kaplan DL, Mayer JM, Ball D, McCassie J, Allen AL, Stenhouse P (1993)
Fundamentals of biodegradable polymers. In: Ching C, Kaplan DL, Thomas EL (eds) Biodegradable polymers and packaging. Technomic Pub Co, Lancaster, pp 1–42
Van de Velde K, Kiekens P (2002) Biopolymers: overview of several properties and consequences on their applications. Polym Test 21(4):433–442
Rouilly A, Rigal L (2002) Agro-materials: a bibliographic review. J Macromol Sci Part C Polym Rev C42(4):441–479
Chandra R, Rustgi R (1998) Biodegradable polymers. Prog Polym Sci 23(7):1273–1335
Yoshito Ikada, Hideto Tsuji (August 19, 1999); Biodegradable polyesters for medical and ecological applications review.
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