seminar on oral lipoid

Oral lipoid formulation and

instability of emulsion

Rahul Uttam Mane

M.Pharmacy(Pharmaeutics)

Rajarambapu college of pharmacy,Kasegaon

RAJARAMBAPU COLLEGE OF

PHARMACY,KASEGAON

1

Content

Introduction

Lipid based Excipients

Classification of lipid based excipients

Techniques for formulation

Characterization of formulation

Introduction of emulsion

Instability of emulsion

Conclusion

References RAJARAMBAPU COLLEGE OF PHARMACY,KASEGAON 2

RAJARAMBAPU COLLEGE OF PHARMACY,KASEGAON 3

INTRODUCTIONDefinition:

It is a solid, liquid and semisolid dispersion of poorly water soluble drugs in lipid and surfactant based excipients for improve oral bioavaibility.

These are generally formulated as self emulsifying, non-emulsifying, micro emulsifying drug delivery systems.

Lipid excipients are generally obtained from natural sources also can be synthesized chemically.

Depending on the choice of excipient(s) and formulation techniques, it is possible to obtain a variety of systems including physical mixtures,liquid/solid solutions, and Self-Micro or Self- Nano Emulsifying Drug Delivery Systems(SMEDDS/SNEDDS).


Lipid based Excipients•Lipids are fatty acids and their derivatives,and substances related biosynthetically or functionally to these compounds.

•The most frequently chosen excipients for preparing oral lipid-based formulations were,

dietary oils-(e.g., coconut or palm seed oil)

long-chain triglycerides-(e.g., corn, oliveor soybean oils)

lipid soluble solvents (e.g.,polyethylene glycol 400, ethanol, glycerin)

Pharmaceutically acceptable surfactants (e.g., Cremophor® polysorbate 20 or 80; D-α-tocopherol polyethylene glycol 1000)


Classification of lipid based excipients

Natural product oils

Semi-synthetic Lipid Excipients

Synthetic Lipid Excipients

Surfactants


Techniques for formulation

1. Spray Cooling


2.Spray Drying


3.Adsorption on Solid Carrier

4.Melt granulation

5.Melt Extrusion

6.Solid dispersion


Characterization of formulation

1.Simulated Lipolysis Release Testing

2.In vitro Dissolution testing


Introduction of emulsionAn emulsion is liquid preparation containing two immiscible liquids, one of which is dispersed as globules (dispersed phase) in the other liquid (continuous phase).

dispersed phase

continuous phase

An emulsion is a thermodynamically unstable system consisting of

at least two immiscible liquid phases one of which is dispersed as

globules in the other liquid phase stabilized by a third substance

called emulsifying agent.

Emulsions are also called heterogeneous systems or biphasic systems

Two Immiscible Liquids

Dispersed Phase(Internal phase)

Continuous Phase(External phase)


Types of emulsions

Simple emulsions (Macro emulsions)

• Oil-in-water (O/W)

• Water-in-oil (W/O)

Multiple emulsions

Oil-in-water-in-oil (O/W/O)

Water-in-oil-in-water (W/O/W)

Micro emulsions

Microemulsions are thermodynamically stable optically transparent , mixtures of a biphasic oil –water system stabilized with surfactants.

(a) Flocculation and creaming

(b) Coalescence and breaking

(c) Phase inversion.

Flocculation

• Neighboring globules come closer to each otherand form colonies in the continuous phase. Thisaggregation of globules is not clearly visible.

• This is the initial stage that leads to instability.

12RAJARAMBAPU COLLEGE OF

PHARMACY,KASEGAON

• The extent of flocculation of globules depends on

(a) globule size distribution.

(b) charge on the globule surface.

(c) viscosity of the external medium.

• Flocs slowly move either upward or downward leadingto creaming.

• Flocculation is due to the interaction of attractive andrepulsive forces, whereas creaming is due to densitydifferences in the two phases.

13RAJARAMBAPU COLLEGE OF PHARMACY,KASEGAON

Creaming• Creaming is the concentration of globules at the top

or bottom of the emulsion.

• Droplets larger than 1 mm may settle preferentiallyto the top or the bottom under gravitational forces.

• Creaming may also be observed on account of thedifference of individual globules (movement ratherthan flocs).

• It can be observed by a difference in color shade ofthe layers.


Coalescence

• If the sizes of globules are not uniform, globules ofsmaller size occupy the spaces between the largerglobules. A few globules tend to fuse with each otherand form bigger globules.

• This type of closed packing induces greater cohesionwhich leads to coalescence.

• In this process, the emulsifier film around the globulesis to a certain extent. This step can berecognized by increased globule size and reducednumber of globules.


Coalescence is observed due to:

Insufficient amount of the emulsifying agent.

Altered partitioning of the emulsifying agent.

Incompatibilities between emulsifying agents.

• Phase volume ratio of an emulsion has a secondaryinfluence on the stability of the product andrepresents the relative volume of water to oil inemulsion.


Breaking

• Separation of the internal phase from the externalphase is called breaking of the emulsion.

• This is indicated by complete separation of oil andaqueous phases, is an irreversible process, i.e., simplemixing fails. It is to resuspend the globules into anuniform emulsion.

• In breaking, the protective sheath around the globulesis completely destroyed and oil tends to coalesence.


PHARMACY,KASEGAON

Phase inversion

• This involves the change of emulsion type from o/w tow/o or vice versa.

• When we intend to prepare one type of emulsion sayo/w, and if the final emulsion turns out to be w/o, itcan be termed as a sign of instability.


PHARMACY,KASEGAON


Conclusion

The oral lipoid formulations are the novel drug delivery system to improve the oral bioavaibility of poorly water soluble drugs.

The most significant issue to consider when formulating poorly water-soluble drugs is the threat of drug precipitation in the lumen of the gastrointestinal tract.

The stability of emulsion is very important in pharmaceutical formulation.


References

ORAL LIPID BASED FORMULATION: A REVIEWM. NAGARAJU PATRO*1, AJIT S. BANKAR, SACHIN UTTAM RAKESH, DR. A. V. YADAV

1.Govt. College of Pharmacy, Karad- 415 124, Tal. Karad. Dist. – Satara, M. S. India.2College of Pharmacy, Medha, At Jawalwadi, Post- Medha, Tal- Jaoli, Dist. - Satara M.S, India.

A REVIEW: NOVEL ORAL LIPID BASED FORMULATION FOR POORLY WATER SOLUBLE DRUGSMAULIK PATEL,SANJAY PATEL,NATVARLAL PATEL AND MADHABHAI PATEL

1.Shri.B.M.Shah,college of pharmaceutical education & Research,Madosa,India.2.Kalol institute of pharmacy,Kalol,India.

Leon lachman, Herbert A Lieberman, Joseph L Kanig, The Theory and practice of Industrial Pharmacy, Third edition, Varghese publishing house, page no: 457- 463.

Lipid-based formulations for oral delivery of lipophilic drugs Martin Kuentz University of Applied Sciences and Arts Northwestern Switzerland, Institute of

Pharma Technology, Gru¨ndenstr. 40, CH-4132 Muttenz, Switzerland

seminar on oral lipoid

Education