This document discusses biopolymers and biomaterials, including definitions of biopolymers as renewable and sustainable polymers derived from biological sources like carbohydrates, proteins, lipids, and nucleic acids. Key properties and applications of common biopolymers like carbohydrates, proteins, and lipids are described. The document also provides an overview of biomaterials, their types and properties, as well as guidelines for evaluating biocompatibility.

1. Advance polymers
(607)
Biopolymers
Dr. Misbah Sultan

2. Books
Biorelated Polymers
Sustainable Polymer Science & Technology
[Emo Chiellini, Helena Gil, Gerhart Braunegg, Johanna
Buchert, Paul Gatenholm, Marten Van der Zee]
Biomaterials
An Introduction
[Joon Parks & R. S. Lakes]
Biomaterials
Principals & Applications
[Joon B. Park & Joseph D. Bronzino]

3. Contents
 Biopolymers introduction
 Biorenewable polymers
• Carbohydrates
• Proteins
• Lipids
• Nucleic acids
 Biomaterials

4. What are Biopolymers?
Any
biorelated
polymeric
material
Biorenewable Biodegradable
Biomaterials

5. Properties of Biopolymers
• Renewable
• Sustainable
• Biodegradable
• Non-Toxic
• Non-Immunogenic
• Non-Carcinogenic
• Non-Thrombogenic
• Carbon neutral

6. Applications of Biopolymers
• Coatings
• Fibers
• Plastics
• Adhesives
• Cosmetics
• Oil Industry
• Paper
• Textiles/clothing
• Water treatment
• Biomedical
• Pharmaceutical
• Automotive
• Rubber

7. Why Biopolymers???
• Carbon neutral…low environmental footprints
Petrochemicals will eventually deplete
Biopolymers are
Renewable & Sustainable industry

8. Biorenewable biopolymers
• Polymers of biological origin
Carbohydrates…..starch
Proteins……haemoglobin
Nucleic acids….DNA
Lipids…..

9. Carbohydrates

10. Carbohydrates
 Carbohydrates are organic compounds
1C:2H:1O
Source of energy……..sugars
Store of energy………..starch
 Structural materials….polysaccharides
 Components of other molecules e.g.
DNA, RNA, glycolipids, glycoproteins

11. Tree of Carbohydrates
Monosaccharide
Disaccharide
Oligosaccharide
Polysaccharide

12. Monosaccharide
• Single monomer of carbohydrate….glucose
• Simple sugar
• 1C:2H:1O
• A source of quick energy

13. Common Monosacchrides
• Glucose – main source of energy
• Fructose – fruits sugar/sweetest sugar
• Galactose – milk sugar

14. Glucose Glucose
Two ring-shape
Structural formula.
versions
Straight chain
glucose
H-C=O
1 Glucose Used in
glucose bending making
|2 starch
H-C-OH
|3
flips
HO-C-H either
| bends way
alpha-glucose
4
H-C-OH
|5
H-C-OH
|6 Used in
CH2OH making
cellulose
Glucose bends itself into 4
different shapes millions of times
a second beta-glucose

15. Monosaccharide isomers
Galactose Glucose Fructose
Same molecular formula, but different
structural formulas

16. Disaccharides
• “Di” means two
• Two monosaccharides combine
• Common Disaccharides are
- Lactose (found in milk)
- Maltose
- Sucrose (table sugar)

17. Disaccharides
Maltose
Sucrose Lactose

18. Polysaccharides
Poly means……..many
Large sugars
Structural materials
Examples
• Glycogen
• Starch
• Chitin
• Cellulose

19. Functions of the Polysaccharides
• Glycogen…….animals energy storage
• Starch……… plants energy storage
• Cellulose ……… cell walls
• Chitin………… the exoskeleton of arthropods

20. Polysaccharides
Cellulose

21. Polysaccharides
Starch

22. Natural synthesis of carbohydrates

23. Proteins

24. Proteins
• Polymers of amino acids covalently linked
through peptide bonds
• Natural organic molecules….C, H, O, N
• Monomers…….amino acids

25. Building blocks of proteins
• There are 20 different amino acids
• All 20 amino acids share the same basic structure
• Every amino acid contains
- an amino group
- a carboxyl group
- a hydrogen atom
- a central carbon atom
- R (alkyl/aryl) group

26. Amino Acid Structure

27. R Groups of amino acids
• Difference in amino acids…….. R groups
• R group……simple or complex
• R groups…different shapes & characteristics

28. Peptide bond
-COOH group of one amino acid joined with
the -NH2 group of the next amino acid through
condensation polymerization

29. Polypeptide
• A long chain of amino
acids…POLYPEPTIDE
• Proteins are composed
of one or more
polypeptides

30. Role of Proteins
• Structural roles…….cytoskeleton
• Catalysts……enzymes
• Transporter………ions and molecules
• Hormones

31. Common example of Proteins
• Many enzymes are proteins
• Biological catalysts
• Lower the activation energy of chemical
reactions
• Increase the rate of chemical reactions

32. Structure of Proteins

33. Sensitivity of Proteins
• Temperature
• pH
• Denature proteins

34. LIPIDS

35. Lipids
• Large, nonpolar organic molecules
• LIPIDS do NOT Dissolve in Water!
• Have a higher ratio of carbon and hydrogen
atoms to oxygen atoms than carbohydrates
• Lipids store more energy per gram than other
organic compounds

36. Categories of Lipids
• Fatty Acids
• Triglycerides
• Phospholipids
• Waxes and Oils
• Steroids

37. Fatty Acids
• Linear carbon chains
• On one end of the carbon chain is a carboxyl
group
• On the other end of the carbon chain is a
methyl group

38. Fatty acid chain
• The carboxyl end is polar and is hydrophilic
• The carboxyl end will dissolve in water
• The methyl end is nonpolar and is hydrophobic
• The methyl end will not dissolve in water

39. Types of Fatty Acids
• Unsaturted fatty acids……carbon chain
contains double bonds
• Saturated fatty acids……carbon chain contains
single bonds

40. Triglycerides
• One molecule of glycerol and three fatty acid
chains
• Saturated triglycerides…butter, fats and red meat
• Unsaturated triglycerides….plant seeds

41. Phospholipids
• One glycerol + two fatty acids + one
phosphate group
• Compose cell membranes

42. Waxes
• A long fatty acid chain joined to a long
alcohol chain
• Waterproof
• Form a protective coating in animals & plants

43. Steroids
• Four fused carbon rings…..cholesterol
• Many animal hormones are steroid compounds

44. Nucleic Acids

45. Nucleic Acids
• Large and complex organic molecules that
store and transfer genetic information in the
cell
• Types of nucleic acids
i. DNA =deoxyribonucleic acid
ii. RNA = Ribonucleic acid

46. Building blocks of Nucleic Acids
• Monomers of nucleic acids are nucleotides
• Components of a nucleotide
- nitrogen base
- sugar
- phosphate

47. Deoxyribonucleic acid (DNA)
• Double helix
• Found in the nucleus
• Stores hereditary information

48. Ribonucleic acid (RNA)
• Is a single helix
• Can be found in the
nucleus and the
cytoplasm of the cell
• Helps build proteins
• Can act as an
enzyme

49. ?????????
Difference between biorenewable
biopolymers and synthetic
polymers????

50. Biomaterials
Science for the benefit of life

51. Biomaterials
Any material used to make devices to replace a part or a
function of the living body in a safe, reliable, economic
& physiologically acceptable manner
OR
Any material used to replace part of a living system or to
function in intimate contact with living tissue
OR
A pharmacologically inert substance designed for
implantation within or incorporation with living system
Natural/synthetic/blend
e.g. sutures, tooth fillings, bone replacements, artificial
eyes etc.

52. Biomaterials market

53. Success of Biomaterial
• Properties & biocompatibility
• Health condition of recipient
• Competency of the surgeon

54. Required characteristics of a
Biomaterial
1. Biocompatibility
2. Pharmacologically acceptable
3. Chemically inert & stable
4. Adequate mechanical strength
5. Sound engineering design
6. Proper weight & density
7. Cost effective
8. Reproducible
9. Easy to process at large scale

55. Types of Biomaterials
Materials Advantages Disadvantages Examples
Polymers (nylon, Resilient Not strong Suture, blood
silicon, polyester) Easy to fabricate Deform with time vessels, hip
May degradable sockets
Metals (Ti and its Strong, tough, May corrode Joint replacement,
alloys, Ag, Au, Ductile Dense dental root
stainless steels) Difficult to prepare implant, pacers,
bone plates and
screws
Ceramics Very Brittle Dental and
(alumina, zirconia, Biocompatible Not resilient orthopaedic
hydroxyapetite) implants
Composites Strong Difficult to prepare Dental resin, bone
(carbon-carbon, Tailor made cement
bone cement)

56. Polymeric Biomaterials
• Natural polymeric biomaterials
Collagen, Chitosan, Alginate
• Synthetic polymeric biomaterials
PVC, PP, PS, PU
• Degradable polymeric biometrials
PLA, PGLA

57. Natural Polymers as Biomaterials
 Polymers derived from living creatures
“Scaffolds” grow cells to replace damaged
tissue
• Biodegradable
• Non-toxic
• Mechanically similar to the replaced tissue
• Capable of attachment with other molecules
 Natural polymers used as biomaterials
– Collagen, Chitosan and Alginate

58. Collagen
• Consist of three intertwined
protein chains, helical structure
• Collagen…..non-toxic , minimal
immune response
• Can be processed into a variety
formats
– Porous sponges, Gels, and Sheets
• Applications
– Surgery, Drug delivery, Prosthetic
implants and tissue-engineering of
multiple organs

59. Chitosan
• Derived from chitin, present in hard exoskeletons
of shellfish like shrimp and crab
• Chitosan desirable properties
– Minimal foreign body reaction
– Mild processing conditions
– Controllable mechanical
– biodegradation properties
• Applications
– In the engineering of cartilage, nerve, and liver tissue,
– wound dressing and drug delivery devices

60. Alginate
• A polysaccharide derived from brown
seaweed
-Can be processed easily in water
-non-toxic
-Biodegradable
-controllable porosity
• Forms a solid gel under mild processing
conditions
• Applications in
Liver, nerve, heart, cartilage & tissue-
engineering

61. Synthetic Polymers as Biomaterials
• Advantages of Synthetic Polymers
– Ease of manufacturability
– process ability
– reasonable cost
• The Required Properties
– Biocompatibility
– Sterilizability
– Physical Property
– Manufacturability
• Applications
– Medical disposable supplies, Prosthetic materials, Dental
materials, implants, dressings, polymeric drug
delivery, tissue engineering products

62. Biodegradable Polymers as
Biomaterials
• Advantages on biodegradable polymer
– Didn’t leave traces of residual in the implantation
– Regenerate tissue
• Desirable properties are
- greater hydrophilicity
- greater reactivity
- greater porosity
Most widely used
Polylactide (PLA), Polyglycolide
(PGA), Poly(glycolide-co-lactide) (PGLA)
Applications
Tissue screws, suture anchores, cartilage repair
Drug-delivery system

63. Biocompatibility of biomaterials
• The ability of a material to elicit an appropriate
biological response in a specific application
without producing a toxic, injurious, or
immunological response in living tissue
– Strongly determined by primary chemical structure
• When an object is incorporated into the body
without any immune responses it is said to be
BIOCOMPATIBLE

64. Standardization of Biomaterials
 FDA (united states food and drug administration)
 Biocompatibility tests
• acute systemic toxicity………denoting the part of
circulatory system
• Cytotoxicity…….toxic in living cell
• Haemolysis….dissolution of erythrocytes in blood
• Intravenous toxicity
• Mutagenesis….permanent genetic alteration
• Oral toxicity
• Pyrogenicity….products produced by heat
• Sensitization…making abnormally sensitive

65. Guidance on biocompatibility
assessment
 Material characterization
• Chemical structure of material
• Degradation products
• Residue level
 Toxicological data
• Biological tests based on clinical trial

66. Guidance on biocompatibility
assessment
 Supporting documents
• Details of
application…shape, size, form, contact time
etc.
• Chemical breakdown of all materials involved
in the product
• A review of all toxicity data
• Prior use and details of effects
• Toxicity standard tests
• Final assessment including toxicological
significance

67. Types of biomaterials based on
surgical uses
Permanent implants
Muscular skeletal system…joints in
upper & lower extremities & artificial
limbs
Cardiovascular system
…valve, pacemaker, arteries, veins
Digestive system…tooth
filling, oesophagus, bile duct
Nervous system…. Dura, hydrocephalus
shunt
Cosmetic implants…..nose, ear, teeth, eye

68. Types of biomaterials based on
surgical uses
Transient implants
Extracorporeal assumption of organ
function….heart, lung , kidney
External dressings & partial
implants….artificial skin, immersion
fluids
Aids to diagnosis….catheters, probes
Orthopaedic fixation
devices….screw, hip pins, bone
plates, suture, surgical adhesives

69. Performance of Biomaterials
• Fracture
• Loosening
• Infection
• Wear
r = 1-f
r is reliability of implant
f is failure

70. Future challenges
• To more closely replicate complex tissue
architecture and arrangement in vitro.
• To better understand extracellular and
intracellular modulators of cell function.
• To develop novel materials and processing
techniques that are compatible with biological
interfaces
• To find better strategies for immune
acceptance

71. Biodegradable
• Natural polymers
Polyhydroxyalkanoates (PHA)
Cellulose composites/membranes
Polylactide acid (PLA)/Starch blends
• Synthetic polymers
Polyesters
Polyvinyl alcohol
Polycaprolactone

72. How to read a paper
• What is research paradigm?...............field with
current state
• What is particular problem area?
• What is author’s thesis & argument?
• What was strategic plan in experimental?
• Does the paper succeed?
• How the work should be followed up on?