Nanotechnology in Drug delivery

By

Femi Emmanuel Ojo

Dept. of Biochemistry

What is Nanotechnology? It is the science, technology and engineering conducted on a nanoscale

What is Drug delivery ? It refers to approaches, formulations, technologies and systems of transporting pharmaceutical compounds to sites where the elucidate their therapeutic effect

Targeted Drug Delivery(Nano-drug Delivery)

• Smart drug delivery• Targeted drug delivery seeks to concentrate the

medication in the tissues of interest while reducing the relative concentration of the medication in the remaining tissues.

• It is believed to improve efficacy while reducing side-effects.

Untargeted and targeted Nano-drug delivery

Method of Targeted Drug Delivery

• Passive Targeting• Active Targeting

Drug Delivery Vehicles(Nanoparticles)

• Liposomes

• Dendrimers

• Polymeric micelles

Liposomes • A liposome is a spherical vesicle having at least one lipid

bilayer.• Liposomes are made from sonicating a dispersion of

amphipatic lipids in water.• Liposomes are most often composed of phospholipids,

especially phosphatidylcholine.• Liposomes have an aqueous core surrounded by the lipid

bilayer.• Liposomes are non-immunogenic,non-toxic,non-hemolytic

and biodegradable.

Dendrimers

• They are highly branched molecules; this makes it easy to bind different chemical groups.

• Each generation double the number of binding sites.

• Small molecules (1-14nm)• Hydrophilic exterior hydrophobic interior• Slightly cationic exterior.

Micelles

Micelles vehicles possess • hydrophobic core and

hydrophilic tail.• The core can be use to

transport lipid soluble and water insoluble drugs.

Application of nanotechnology in treatment of cancer

• Liposomal doxorubicin (doxil,myocet) is an anti cancer drug.

• To reduce cardiotoxicity• Increase efficacy

• The PEG liposomal coating allows DOXIL to evade detection and destruction by the immune system and, as a result, increase the blood circulation time* Half-life of approximately 55 hours.

• DOXIL has a small steady state and, therefore, is confined mostly to the vascular fluid and Remains stable in blood.

Mechanism of action

•Alkylation-formation of ‘doxorubicin-DNA ’ adducts•Inhibiting topoisomerase

ConclusionNanotechnology in drug delivery is efficient because;

• they are basically small (<100nm)• they are made up of biodegradable molecule

like lipid, polymers e.t.cAlthough there exists an economic problem of the costing for production. Nevertheless the future remains exciting and wide open