Nanotechnology

Question 1

What is the size range of nanoparticles?

Answer 1

10-1000nm

Question 2

What are the three types f Nanotechnology based DDS

Answer 2

Polymer based nano
Nanoemulsions
Solid lipid nanoparticle

Question 3

What are polymer based nanoparticles

Answer 3

polymeric colloidal particles which a therapeutic agent can be embedded or encapsulated in the polymer matrix

Question 4

Nanocapsule vs Nanosphere
Where is the drug located?

Answer 4

Nanocap: Drug is in reservoir in nanoscale and it is encapsulated in the membrane

Nanosphere: drug is dispersed in polymer matrix

Question 5

What is the classification of polymers used in nanoparticles

Answer 5

Natural or synthetic

Synthetic can be either biodegradable or non biodegradable

Natural are always biodegradable

Question 6

E.g. of naturally occuring biodegradable and biocompatible polymers

Answer 6

Cellulose
Gelatin
Chitosan
Crabshell ( biocompatible)

Question 7

e.g. of synthetic biodegradable

Answer 7

Polylactic acid
Poly-(lactide-co-glycolide)
Polyanhydrides
Poly-alkyl-cyanoacrylate

Question 8

Non biodegradable synthetic polymers

Answer 8

polystyrene (used only for diagnostic imaging purpose)

Question 9

What are Methods of preparation of polymer based nanoparticles?
(they are versatile)

Answer 9

Solvent evaporation method (emulsion solvent evaporation method)
Ionotropic gelation

Question 10

Explain the solvent evaporation method
How do to prepare polymer?
Drug is dissolved where?
After the emulsion is formed, kif it is converted to nanoparticle?

Answer 10

Preparation of polymer solution in volatile solvent

Drug is dissolved in solution and the organic phase is emulsified under agitation in dispersing phase which contains a suitable emulsifying agent

The emulsion is then converted into nanoparticle suspension on evaporating the solvent

Question 11

E.g. of volatile solvents

Answer 11

dichloromethane
chloroform
ethyl acetate
They should easily evaporate at <40 degrees

Question 12

In solvent Evaporation Method:
Aqueous phase is what?
Organic phase is what?
Step one is what?
Step two is what?

Answer 12

Aqueous phase is o/w e.g. tween + water
Organic is oily phase
Step one is emulsification
Step 2 evaporation while stirring continuously
(ppt solid nanoparticle and colloidal dispersion)

Question 13

Explain Ionotropic gelation Method
What does it involve?

Answer 13

Involves the addition of alkaline tripolyphosphate (TPP) solution (pH=7-9) into acidic chitosan solution pH= 4-6

Question 14

What is the method of synthesizing hydrogel NPs using polymers like chitosan, and what is the significance of the presence of NH2 groups in these NPs?

Answer 14

Polymers such as chitosan produce hydrogel NPs
They are synthesized by Ionotropic method
Contains NH2 that will be protonated

Question 15

Ionotropic Method in pictures

Answer 15

Chitosan is dissolved in acetic acid tp lead catanionic group
Drug is dissolved in this solution after chitosan formation
Addition of TPP (-ve charge) drop wise while stirring cont. to avoid ppt of two opp charges

Question 16

What are nanoemulsions

Answer 16

o/w Non ionized oily globules
Also known as submicron emulsions, Ultrafine or mini emulsions

They are Submicron sized colloidal particulate Systems

(we use lipophilic drugs)

Question 17

What drugs do nanoemulsion deliver? What do they serve as? What do they do to bioavailability

Answer 17

Serve as aqueos dosage form of water insoluble drugs
Deliver lipophilic drugs after solubilization
Enhance bioavailability

Question 18

What are the techniques used

Answer 18

High pressure homogenization
Micro fluidization
Ultrasonication

Question 19

What is High pressure Homogenization

Answer 19

A mixture is forced to pass through an orifice at very high pressure

The result product is further subjected to intense turbulence and impaction forces resulting in emulsion with extremely fine particles

For 10-1000nm

Question 20

What is the only drawback of High Pressure Homogenization

Answer 20

The rise in temperature of emulsion during processing
Thus it is not good for heat labile drugs

Question 21

what is the solution for high temperature in HPH

Answer 21

Use ice bath (water jacketed)

Question 22

Factors affecting size

Answer 22

Surfactant
Drug
Oil
Ratio of o to w
The process can be repeated to achieve results

Question 23

What is Microfluidization

Answer 23

It utilizes a high pressure pump
Products are pushed out through the interaction chamber
The chamber consists of stainless steel microchannels
The impingement area results in the formation of small particles
The particles are of submicron size

Question 24

What is the advantage of microfluidlization to high pressure?

Answer 24

F 3anda cooling coil

Question 25

Ultrasonication technique
Hiye 3ibara 3an shu
How is the size of particles reduced?

Answer 25

emulsion is exposed to agitation at ultrasonic frequency of 20 kHz
Reduces droplets to nanodroplets
Produces mechanical vibration when the sonicator tiip contact with liquid
Leads to cavitaion thus size reduction

Question 26

Solid Lipid Nanoparticles definition

Answer 26

The oil of fat emulsion is replaced by solid lipid

Question 27

Examples of Solid lipids

Answer 27

glyceryl monostearate
Stearic acid 3ando more sustained effect and more stable
Tristearin

Question 28

What is the process of forming solid lipid nanoparticles

Answer 28

1- Lipid is melted
2 Lipophilic drug is added to lipid emulsion
3- Prepare aqueous phase (H2O + Emulsifying agent)
4-Heat the aqueous phase at high temp
5- Dispersing the lipid in aq phase
6- Homogenization
7- Ultrasonication of the emulsion
8- Formation of colloidal emulsion
9- Upon cooling with continuous stirring, solid lipid nano are formed
10- They can undergo centrifugation to collect the nanoparticles

Question 29

In Solid lipid nanoparticles, why is homogenization done ultrasonication

Answer 29

To yield small nanoparticles