NANOMEDICINE & DRUG DELIVERY SYSTEMS
UNIT 1-PROSPECT OF NANOMEDICINE
BIO-PHARMACEUTICALS
Seminar byR.DELMA JONES RUFINA
II M.Tech-NST
PREAMBLE
Biopharmaceuticals are medical drugs produced using biotechnologyThey are proteins (including antibodies), nucleic acids used for therapeutic or in vivo diagnosticproduced by other than direct extraction from biological source
First Substance Approved For Therapeutic Use:biosynthetic 'human' insulin (humulin) made via recombinant DNA technology
a pharmaceutical product manufactured by biotechnologymethods (involving live organisms;bioprocessing);
CLASSIFICATIONAccording to biological roles of proteinsEnzymes – Catalyses virtually all chemical reactions i.e. 6GDH Transport proteins i.e. Haemoglobin of erythrocytes Contractile or Motile proteins i.e. Actin and Myosin Structural proteins i.e.Collagen Defense proteins i.e. Immunoglobulins and Antibodies Regulatory proteins i.e. insulin Nutrient and storage proteins i.e. Ovalbumin
Thrombolytic agents (tissue plasminogen activator) plasminogenplasmin protein involved in blood clot removal
Hormones (insulin, glucagon, growth hormone, gonadotrophins) CS Factor glycoprotein harmone binds to hemopoietic stem cellsHaematopoietic growth factors (Erythropoietin) gylcoprotein harmone controls erythropoiesis
Interferons (Interferons-α, -β, -γ) proteins relesed by lymphocytes
Monoclonal antibodies (Various)
SOME EXPLANATIONS………………
BIOPHARMACEUTICALS PRODUCTION
Biotechnology makes large-scale production of existing substances using microbial cells mammalian cell lines,tissues plant cell cultures, whole cultivation
Mechanism behind is TransgenicDNA recombinant technology
MECHANISM
Strengths:Access new manufacturing facilitiesHigh production rates/high protein yieldRelatively fast 'gene to protein' timeSafety benefits;no human pathogensStable cell lines/high genetic stabilitySimple medium (water, minerals & light)Easy purification
Weaknesses:No approved products yet (but Phase III)No final guidelines yet (but drafts available)
Threats:Food chain contaminationSegregation risk
PLANT BIOPHARMACEUTICALS
SOURCE
PRODUCTS
Very large and unstable molecules held by weak non-covalent forces
Easily destroyed by relatively mild storage conditions
Hard to obtain in large quantities
Elimination by B and T cells
Proteolysis by endo/exo peptidases
Small proteins (< 30 kD) filtered out by the kidneys very quickly
Unwanted allergic reactions may develop (even toxicity)
Loss due to insolubility/adsorption
Noncovalent Covalent
Denaturation - Deamidation
Aggregation - Oxidation
Precipitation - Disulfide exchange
Adsorption - Proteolysis
CHALLENGES IN PROTEINS
Storage
Delivery
Formulation
• Addition of stabilizing salts or ions (Zn+ for insulin)
• Addition of polyols (glycerol and/or polyethylene glycol) to solubilize
• Addition of sugars or dextran to displace water or reduce microbe growth
• Use of surfactants (CHAPS) to reduce adsorption and aggregation
Refrigeration
Freeze-Drying
Additives
STORAGE MECHANISM
PROTEIN FORMULATION
Protein sequence modification
(site directed mutagenisis)
PEGylation
Proteinylation
Peptide Micelles
Formulating with permeabilizers
1.Site Directed Mutagenesis:
Allows amino acid substitutions at specific sites in a protein
i.e. substituting a Met to a Leu will reduce likelihood of oxidation
Strategic placement of cysteines to produce disulfides to increase Tm
Protein engineering (size, shape, etc.)
E343H
2.PEGylation
+C
H-C
H-C
H-C
H-C
H-C
H-C
H-C
H-C
H-C
H | | | | | | | | | |O
H O
H O
H O
H O
H O
H O
H O
H O
H O
H
PEG is a non-toxic, hydrophilic, FDA approved, uncharged polymerIncreases in vivo half life Decreases immunogenicityIncreases protease resistance, solubility & stability
Peptide-PEG monomers
Peptide Peptide
O
R3HNH
O
R4HH3N+
O
R1HNH
O
R2HNH
O
O
R3HNH
O
R4HH3N+
O
R1HNH
O
R2HNH
O
Hydrophobic block Hydrophobic block
cont……
+
Protein Drug ScFv (antibody)
Attachment of additional or secondary (nonimmunogenic) proteins for in vivo protection
Increases in vivo half life (10X)
Cross-linking with Serum Albumin
Cross-linking or connecting by protein engineering with antibody fragments
3.Proteinylation
4.Formulation with permeabilizers
Salicylates (aspirin)
Fatty acids
Metal chelators (EDTA)
Anything that is known to “punch holes” into the intestine or lumen
DELIVERY
Polymeric drug delivery Microencapsulation Liposomal delivery Niosomal delivery
MECHANISM Proteins in pumps Oral protein delivery Nasal delivery Pulmonary delivery Ocular delivery Patch delivery
LEVELS OF TESTING
DRUG + receptor
BINDING
+ transductionsystem (secondmessenger; enzyme)
Biochemical Testing
Functional whole or part organs
Isolated Tissue Experiments
Anaesthetised Or Conscious Animals
Whole Animal Experiments
{Phase 0 (non-clinical)}Phase 1 (volunteers)Phase 2 (patients)Phase 3 (large scale multi-centre)Phase 4 (post registration monitoring)
NANO BIOPHARMACEUTICALS
Nanoparticles including various nanodimensional entities such as
molecular imprinted polymers
metallofullerenes
prodrug delivery
oral, injectable and implantable, pulmonary, and transdermal and
transmucosal delivery have come up.
THANK YOU...
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