Gels Flashcards
Define the gels
It is a semi-solid dispersion system containing a gelling agent in sufficient quantities to impart a 3 dimensional polymeric matrix.
Gels containing a preservative such as …..
Methylparapen, propyleparaben
Gels may contain stabilizers such as…..
EDTA
What are the gelling agents ?
These are substances when added to an aqueous mixture increase its viscosity without modifying its other properties.
What are the importance of the gelling agents?
Providing body.
Increase stability.
Improve suspension of added ingreadients.
What are the types of gelling agents?
1_ natural polymers: *proteins *polysaccharides 2_ semi-synthetic polymeres: * celluse derivatives. 3_ synthetic polymers
Define the controlled release gel
A controlled released drug or preparation is released into the body in specified amount and over a period of time.
The controlled release syatem is designed to release the drug active ingredients gradually over time.
Define the Organogel.
Is a non crystalline, non glassy thermo reversible solid materials composed of liquid organic phase enterapped in a three dimantionally cross linked network.
Gels in which vehicles has been removed leaving a polymer network
Xerogel
Type of Gel have usually retain high porodity (15-50%)
Xerogel
Type of gel formulated from polymer with solvent like glycerin or poly ethylene glycol
Have no water
Non aqueous gel
Define the thermosensitive sol-gel revirsible hyrogel.
Aqurous polymer solution that are transformed into gels by changes in inviromental condition as PH and temp.
Define the Emulgel.and what is the importance of it ?
It is the formulation of emulsion and adding a gelling agent to convert the emulsion into gel.
The importance:
1This preparation is capable of holding hydrophilic as well as hydrophopic drugs.
2 the micro/nano emulsion allow faster and better absorption of the preparation.
Define the paste.
Semi solid preparation containing high conce. Of insoluble powdered substances(20%) dispersed in a sutible base.
Less grasy and moreabsorptive, stiffer in consistency than ointment
Paste
What are the characterstics of pastes?
1_Stiffer than other semisolid preparation, hence it is stable on the site of application.
2_Don’t interfer with non infected area.
3_Less greasy than ointment.
4_Used in case of lesions.
What are the types of pastes?
1_Ointment-like.
2_Jelly pastes.
How can we classifing the pastes?
1_Fatty pastes:
This formulation are consist of fatty or oleoginous bases.
2_Aqueous Gel Pastes:
This are prepared with water miscible bases.
3_Hydrocolloid Pastes:
This consist of hydrocarbon bases.
Zinc oxide paste is an example on …..
Fatty pastes
Sodium hydroxymethylcellus, and Titanium dioxide pastes are example on …..
Aqueous gel paste
Tooth pastes, Oxide gelatin pastes are example on ……
Hydrocolloid pastes.
Is indicated for aphthous alcer (Cancke sores)
Apsol
Define the toothpastes.
Is a paste or gel dentifrice used to clean and improve the appearance of health of teeth.
Used to promote good oral hygiene and remove of dental plaque and food.
What are the characters of tooth pastes?
Free from gritty particles Good taste and flavour. Stable. Not dry upon standing. Have suitable consistency.
