Application of emulsion

Following are the application of emulsion in different way:

1.   Milk is also example of emulsion. In which fat is soluble in water phase.

2.   Asphalt which used in preparation of roads is a emulsified in water is used for without the necessity of melting the asphalt.

3.  Many insecticides and pesticides which used in agriculture are also one type of emulsion.            

4. Paints and inks are also prepared by emulsification.

5. The digestion of fats process is also example emulsification. The absorption of  fats is the emulsification process.

6.  Cosmetics like cream and lotion are also prepared by emulsification method. Emulsified cosmetics have fine texture and a smooth touch upon application, so sustained release of the active ingredient from continues phase of emulsion can increase skin penetration of active ingredients and thus increase their concentration into the skin.

7.   Many Shampoo and hair conditioners are also example of emulsion. HLB scale or HLB system is used to decide which emulsifying agent is used.

8.   Emulsions can protect active molecules such as vitamins C and E from the external phase from oxidation.

9.   Emulsion is also used as antiaging products and sun skin lotion.

10.  The wet wipes which used for make-up removal, face care, body care & baby care products. In these products also emulsion is used.

11.   Some emulsion products are also patented for manufacturing.

12. Example: emulsion of acid fatty acid esters and its uses in cosmetics, dermatological, pharmaceutical or ophthalmology fields by L’Oreal Paris.

emulsion based on ethylene oxide and propylene oxide block co polymers  which used in the  cosmetics, dermatological or ophthalmology fields by L’Oreal Paris

13.  low viscosity  emulsion  such as  Spray  and aerosols are  used  as cosmetics

14.    Emulsion is also used in screen printing, making the stencils. photo emulsion also used.

15. Emulsion is also used in food industry. Some food products are also made by emulsification process

    16. Mainly emulsion is prepared as different dosage form for detailed information of  refer article Application of emulsion in pharmaceutical industry.

Difference between Emulsion and Suspension 
Definition of Emulsion, Types of Emulsion  
Pharmaceutical industry and Emulsion 
HLB Scale and Emulsifying Agent  
Emulsifier or emulsifying agent and emulsion

pharmaceuticals industry and emulsion

Application of emulsion in pharmaceuticals industry

Pharmaceutical emulsion can be used

• As parenteral preparation
• As ophthalmic preparation
• As  Aerosols
• As Ointment
• As Cream and lotion.
• As a diagnostic purpose

Emulsion is used as a oral dosage form :

•   Emulsions also enhance the oral absorption bio availability of the poor water soluble drugs.
•   Emulsion is most widely used to deliver drugs into the body. Emulsions are worked    as a carrier for drug molecule. It provides carrier for low water soluble drugs.
•   Oral it decreases the unpleasant taste and improves the absorption
•   Oral emulsions mostly O/W.To enhance palatability of oils when given orally. 

Emulsion as Panenteral:

•   Lipid emulsion is most widely used as Panenteral dosage form.
•    Lipid emulsion used to provide the nutrient to the body by Panenteral way.
•    Nutrient oils are injected intravenously in the form of emulsions which are unable to swallow. 
• Some emulsion used as injections. emulsion reduce the pain and irritation  of the inject able preparation example: Amphotericine, diazepam, propofol
•  Emulsion decrease the toxicity of the some drugs. Ex: Amphotericine, diazepam, propofol
• Emulsion also Improved Stability and Solubility of the intravenous preparation

Emulsion as aerosol:

•   Emulsion of the finely divided drug substance typically is dispersed in the
•  liquid propellant with the aid of suitable biocompatible surfactants or other excipients. Propellants for aerosol formulations are typically low. The two-phase formulation consists of drug(s) dissolved in liquefied propellant. Liquid co solvents such as alcohol, propylene glycol, and polyethylene glycols often are added to enhance the solubility of the drug substance.

For sustained drug release and depot formulation:

• water-soluble drug  solubilize into the   water phase of the emulsion globule, which showed prolonged release properties and lessen toxic effects
• Most of the water soluble antigents and some drugs are formulated as water in oil type emulsions for depot injection purpose (sustain and release).

Topical emulsion

•  topical emulsions are creams which have emollient properties. topical form of emulsion  prevent the trans epidermal water loss, enhanced skin smoothness and penetration of active ingredients.
• Gel emulsion mean emulsion in gel which is also known as emugel. Antifungal drugs are applied in this form on the skin.

Other Application:

• Some of the perflorinated hydro-carbons are formulated as oil in water emulsions used for oxygen replacement therapy.
• Some of the emulsions containing radio opaque substances are used for diagnostic purpose.
•  Emulsion based wet wipes for such applications as baby care and make-up removal.

Related Article:

Difference between Emulsion and Suspension 
Definition of Emulsion, Types of Emulsion  
Application of Emulsion 
HLB Scale and Emulsifying Agent  
Emulsifier or emulsifying agent and emulsion

HLB Scale (hydrophile-lipophile balance) and emulsifying Agent

HLB Scale (hydrophile-lipophile balance) and emulsifying Agent:

We discussed about the emulsifying agent(emulsifier). 

To select appropriate emulsifying agent we used the HLB SCALE system.

HLB Scale  means hydrophile-lipophile balance.

HLB  system was developed by William C. Griffin to proper selection of the emulsifying agent.

All emulsifying agents have lipophilic and hydrophilic part. HLB value of emulsifying agent is based on the lipophilic and hydrophilic group present into the emulsifying agent.

  

The HLB value is an indication of the solubility of the Emulsifying agent.Generally HLB scales  apply to the non-ionic surfactant.

HLB system has an arbitrary scale of 1 - 18.

HLB RANGE	USE
0-3	Anti foaming agent
4-6	W/O emulsifying agent
7-9	wetting agent
8-18	O/W emulsifying agent
13-15	Detergents
10-18	stabilizing agent

                                                                                                                                                                                                                                          -Higher the HLB value means more number of hydrophilic groups in the molecule.

                  Mean more water soluble or hydrophilic the surfactant is.

                   

-The lower the HLB value the more lipophilic or oil soluble the surfactant  mean more lipid soluble or lipophilic surfactant is.

-Emulsifying agents exhibiting an HLB between 3 to 6 are used to produce w/o emulsions.so they are known as w/o emulsifying agents.

-Example: span 80

-HLB value span 80 of  4.3  

-Emulsifying agents that exhibit an HLB between  6 to 9 form non-stable milky dispersion in water.

-Example: span 40

-HLB Value of span 40 is  6.7

-Emulsifying agents exhibiting an HLB between  9 to 16 are used to produce o/w emulsions. so they are known as o/w emulsifying agents. 13–16). Examples include:

-Example: Tween 65

-HLB value of Tween 65 is 10.5

some example:

HLB RANGE	USE
PEG 400 Monostearate	11.6
Span 40	6.7
Span 20	8.6
Tween 20	16.7
Tween  40	15.6
Tween 65	10.6
Tween 85	11.0
Sodium oleate	18

 

 

Emulsifier or emulsifying agent and emulsion

Emulsifier or emulsifying agents are the substance which used to increase the stability of emulsion.

  

It is also known as the emulgent. Emulgent (Emulsifying agent) is also known as the surfactants.

  

These agents have both a hydrophilic and a lipophilic part in their chemical structure.HLB scale is used to decide the which emulsifying agents shall be used 

Emulsifying agent works by following way:

1) Formation of a protective barrier

2)Reduction of interfacial tension

3) Decreasing the potential for coalescence by forming an electrical double layer.

some commonly used emulsifying agents include tragacanth, sodium lauryl sulfate, sodium dioctyl  sulfosuccinate, Spans, Tweens, CMC, poly sorbate 

Emulsifying agents can be classified according to Chemical structure

• Natural emulsifying agent
• Semi synthetic emulsifying agent
• Synthetic emulsifying agent

• Natural emulsifying agent:

The emulsifying agent which derived from natural origin is known as the natural emulsifying agent.

They are may b from plant origin or animal origin.

The plant origin emulsifying agent is carbohydrates and include gums and mucilaginous substances. They are variable in chemical composition and their emulsifying property.

Agar, tragacanth, alginates, gum, pectins,acacia, starch are the example of natural plant origin emulsifying agents.

The animal origin emulsifying agent :

Gelatin, albumin, Lecithin, cholesterol

• Semi synthetic emulsifying agent:

Semi synthetic emulsifying agent is the emulsifying agent which are mainly from cellulose derivatives.

methylcellulose, carboxymethylcellulose are example of semi synthetic emulsifying agents

• Synthetics emulsifying agent:

The agent which synthetically derived.

They are categorized as 

Cationic:

Cationic emulsifying agents are the emulsifying agent in which hydrophilic side content positive charged ion.

Example: benzalkonium chloride, benzethonium chloride

Anionic:

anionic emulsifying agents are the emulsifying agent in which hydrophilic side content negative charged ion.

Example: sodium oleate potassium oleate, triethanolamine stearate, detergents (sodium lauryl sulfate, sodium dioctyl sulfosuccinate, sodium docusate).

 Nonionic:

Nonionic emulsifying agents are the emulsifying agents in which hydrophilic both positive and negative charges.

 Example:

sorbitan esters, Spans, polyoxyethylene derivatives of sorbitan esters (Tweens), glyceryl esters 

Difference between Emulsion and Suspension 
Definition of Emulsion, Types of Emulsion  
Application of Emulsion 
Pharmaceutical industry and Emulsion 
HLB Scale and Emulsifying Agent  
What is Mayonnaise Emulsion