This presentation delivers about basics of natural polymer based nanomaterials.

1. NATURAL POLYMER -BASED-
NANOMATERIALS
 AROCKIYA NISHA ARUL THOMAS
 Department Of Nanoscience And
Technology
 Alagappa University, Karaikudi

2. INTRODUCTION
 Polymers are large molecules made up of
repeating units called monomers.
 These molecules form long chains, with
thousands of monomer units linked
together.
 The process of linking monomers to form
a polymer is called polymerization.
 There are various types of polymers,
 natural polymers
 synthetic polymers
 semi-synthetic polymers.

3. Natural Polymers
 They occur naturally and are found in plants and animals.
 For example, proteins, starch, cellulose and rubber.
Semi-synthetic Polymers
 They are derived from naturally occurring polymers and undergo
further chemical modification.
 For example, cellulose nitrate and cellulose acetate.
Synthetic Polymers
 These are human-made polymers. Plastic is the most common
and widely used synthetic polymer. It is used in industries and
various dairy products.
 For example, nylon-6, 6, polyether, etc.

4. NATURAL POLYMERS
 Natural polymers are large molecules composed of repeating
subunits (monomers) that occur in nature and are synthesized by
living organisms.
 Natural polymers often have complex structures and serve a wide
range of functions within organisms.
 examples of natural polymers includes, that are Chitin, Cellulose,
Starch, Proteins, Collagen, etc,..

5. CONT….
 Natural polymers are abundant in nature and have a wide range
of applications across various industries due to their unique
properties and biocompatibility.
 Here's how they are utilized in different sectors like,
Food Industry
Pharmaceuticals and Medical Applications
Textiles
Packaging and Biodegradable Materials
Cosmetics and Personal Care

6. Natural Polymer-Based Nanomaterials
 They refers to nano-sized structures and materials that are
composed primarily of natural polymers or biopolymers.
 It can include nanoparticles, nanofibers, nanogels,
nanocomposites, and other nanostructures formed from natural
polymers.
 These materials can be engineered for various purposes, such as
drug delivery, tissue engineering, wound healing, food packaging,
water purification, and more.
1. Gelatin Nanoparticles
2. Albumin Nanoparticles
3. Lectins Nanoparticles
4. Alginate Nanoparticles
5. Dextran Nanoparticles
6. Chitosan Nanoparticles
7. Agarose Nanoparticles

7. Chitosan nanoparticle
Structure and properties

8. Chitosan
STRUCTURE:
 Chitosan is a biopolymer derived from chitin, found in the shells of
crustaceans like shrimp and crabs.
SOURCES OF CHITIN - -

9. NANOPARTICLE FORMATION:
 Chitosan nanoparticles are typically formed through techniques like
ionotropic gelation, emulsification, and self-assembly.
 Manipulating parameters like pH and concentration leads to different
nanoparticle sizes and properties
MUCOADHESIVENESS:
 Chitosan nanoparticles exhibit mucoadhesive properties, allowing them to
adhere to mucosal surfaces.
 Useful for drug delivery to mucous membranes and improving
bioavailability.

10. SIZE AND MORPHOLOGY:
 Chitosan nanoparticles vary in size from tens to hundreds of nanometers.
 They can be spherical, rod-shaped, or other morphologies based on synthesis
methods.
SURFACE CHARGE AND ZETA POTENTIAL:
 Chitosan nanoparticles carry a positive charge due to the presence of amino groups.
 Zeta potential indicates particle stability and their ability to interact with negatively
charged surfaces.
Biocompatibility and Biodegradability:
 Chitosan is biocompatible and non-toxic, making it suitable for various
applications.
 Its biodegradability reduces environmental impact and avoids long-term
accumulation.
Antibacterial Activity:
 Chitosan's positive charge interacts with bacterial cell walls, disrupting their
integrity.
 Shows promise in wound healing and as an antimicrobial agent.

11. Preparation
Synthesis of
Chitosan
Nanoparticle
Micro
emulsion
Co-
precipitation
Reverse
miiceller
Ionotropic
gelation
Microfluidic
Coacervatio
n
Ultrasonicati
on
Desolvation
method

12. PREPARATION OF CHITOSAN NANOPARTICLES
Ionotropic gelation
Chitosan is poured into an acetic acid solution
or added with a stabilising agent, such as
poloxamer
Then the tripolyphosphate aqueous solution
kept under vigorous stirring.
Then anionic particles diffuse into the chitosan
molecules and cross-linking occurs
nanoparticle formation with a size range of 200–
1000 nm,
 After a couple of centrifugations and washing
with water.
ChNP are collected by freeze-drying or oven-
drying.

13. Chitosan nanoparticle for drug delivery
1. Drug loading

14. Both water soluble and water – insoluble drug can be
loaded

16. 2.Drug Release
 In vitro release also depends upon
1. pH of media
2. Polarity of particle
3. Presence of enzymes in the dissolution media

17. Schematic illustration of target-drug chitosan
nano polymer:

18. Chitosan Nanoparticles-Based Cancer Drug
Delivery

19. Alginate nanoparticle
Structure and properties

20. Alginate
Alginate Structure:
 Alginate is a natural polysaccharide derived from brown algae.
 Composed of linear chains of mannuronic acid (M) and guluronic acid (G)
units.
Nanoparticle Formation
 Alginate nanoparticles are formed through techniques like ionotropic
gelation and coacervation.
 Ionic interactions between alginate and divalent cations (e.g., calcium
ions) lead to nanoparticle formation.
Size and Morphology:
 Alginate nanoparticles can range from tens to hundreds of nanometers in
size.
 Morphology depends on synthesis conditions, including spherical and
irregular shapes.

21. Crosslinking and Stability:
 Alginate nanoparticles are stabilized through crosslinking with
divalent cations.
 Ionic bonds enhance stability and prevent aggregation.
Biocompatibility:
 Alginate is biocompatible and non-toxic, making it suitable for
various applications.
 Alginate-based materials have been used in drug delivery and
tissue engineering.

22. Applications of alginate
 Due to its special properties, alginate is one of the most used polymers in microparticle’s formation.
 Currently, alginate is less commonly used in the formation of alginate nanoparticles.
 Alginates have some common applications, such as in
 Food and beverage industry, drinks stabilizers, icecream stabilizers, jelly Stabilizers, ethanol production,
pharmaceutical industry, cell culture and transplantation, dental impression material, tablets, and in wound
dressing and can also be used in other industries, including fabrics, papers, paints as well as toothpastes

24. 3D cell culture in the biomimetic chondroitin sulfate (CS)-modified
alginate hydrogel beads (ALG-CS) and the ALG-CS network.
1. Tumor cells were suspended in a mixed solution of alginate and CS.
2. The mixture was extruded into CaCl2 solution to form beads using a
high-voltage electrostatic droplet generator.
3. Beads containing cells were cultured for 7 days.
4. The traditional alginate hydrogel beads (ALG) without CS were
prepared as a control via the same procedure.
5. ALG-CS has a novel network that differs from that of the traditional
ALG.
6. Alginate chains not only produce the traditional egg-box structures
but also can form asymmetric egg-box-like structures with CS chains
via the coordination of calcium ions, which creates a CS-modified
biomimetic alginate hydrogel that mimics the tumor
microenvironment with increased expression of CS.

25. Drug Delivery
 Alginate nanoparticles can encapsulate drugs due to their porous
structure.
 Controlled release mechanisms based on nanoparticle degradation and
diffusion.
Biomedical Applications
 Alginate nanoparticles are used in tissue engineering and regenerative
medicine.
 Scaffold incorporation enhances cell adhesion, growth, and differentiation.
Food and Nutraceuticals
 Alginate nanoparticles can encapsulate bioactive compounds for targeted
delivery.
 Used in the food industry for encapsulating flavors, nutrients, and
additives.

26. Cellulose nanocrystals
Structure and properties

27. Cellulose
 Cellulose nanocrystals (CNCs) are nanoscale particles derived from
cellulose, a natural polymer found in plant cell walls.
 They exhibit unique properties that make them valuable for various
applications.
Nanocrystal Extraction
 CNCs are obtained by breaking down cellulose fibers through acid
hydrolysis or enzymatic methods.
 Hydrolysis removes amorphous regions, leaving behind nanocrystals.

28. Size and Shape
 CNCs have dimensions in the nanometer range, typically ranging from 5 to
100 nanometers in length.
 They have a rod-like shape, with a high aspect ratio.
Crystallinity
 CNCs have a high degree of crystallinity due to the removal of amorphous
regions during extraction.
 Crystalline structure contributes to their strength and stiffness.
Surface Chemistry
 CNCs possess hydroxyl groups on their surface, making them reactive and
suitable for functionalization.
 Surface modifications enhance compatibility with other materials and
applications.

29. Preparation of CNCs

30. CELLULOSE NANOCRYSTAL AS A SCAFFOLD

31. Evaluation of cellulose nanocrystal/poly(lactic acid) in situ nano
composite scaffolds for tissue engineering
1. A CNC/PLA in situ nano composite scaffold
was developed for tissue engineering.
2. The scaffolds showed excellent mechanical
performance and hemocompatibility.
3. Degradability and bio mineralization of the
scaffolds were improved with the CNCs.
4. Cell culture studies proved the enhanced
cell viability of the scaffolds.

32. Gelatin Nanoparticles
Structure and properties

33. Gelatin
Gelatin Structure:
 Gelatin is a protein derived from collagen, found in animal connective tissues
and bones.
 Composed of amino acids like glycine, proline, and hydroxyproline.
Nanoparticle Formation:
 Gelatin nanoparticles are typically formed through techniques like coacervation,
crosslinking, and emulsification.
 Variables like pH, temperature, and concentration influence particle size and
properties.
Size and Morphology:
 Gelatin nanoparticles can range in size from tens to hundreds of nanometers.
 Morphology varies, including spherical and irregular shapes based on synthesis
methods.

34. Surface Charge and Zeta Potential:
 Gelatin nanoparticles carry charges depending on pH and amino acid
content.
 Zeta potential affects stability and interactions with other charged particles.
Biocompatibility and Biodegradability:
 Gelatin nanoparticles are biocompatible, meaning they are well-tolerated by
living organisms and their cells.
 They are biodegradable, meaning they can be broken down into non-toxic
byproducts, reducing environmental impact.
Antimicrobial activity:
 Gelatin nanoparticles inhibit the growth of various bacterial species, including both
Gram-positive and Gram-negative bacteria.
 Their effectiveness is attributed to the interaction between positively charged gelatin
and negatively charged bacterial surfaces.

35. Properties of Gelatin used in anticancer DDnS

36. CHALLENGES AND FUTURE DIRECTIONS
 Ongoing research and future directions in the field of natural polymer-based
nanomaterials focus on expanding their applications.
 improving their properties, and addressing various challenges in medicine,
food, and beyond, while addressing challenges such as safety and scalability

37. Thank you…!