Solutions Flashcards
The maximum concentration of the solute dissolved in that particular solvent
Solubility of solute in particular solvent
Factors affecting solubility
⚫ Temperature
⚫ Pressure
⚫ pH of solution
⚫ State of division of solute/particle size
⚫ Physical agitation
⚫ Physicochemical properties of the solute &
solve
Solubility of solute in particular solvent
The maximum concentration of the solute dissolved in that particular solvent
results in the liberation of solute
molecules from the solid phase to the liquid phase
Interfacial tension
solute molecules must migrate through the boundary layers surrounding the crystal to the bulk of solution
Migration
involves a phase change so that
molecules of solid become molecules of solute in the solvent in which the crystal is dissolving
Interfacial Tension
a process of relocation of solute molecules from an environment where they are surrounded by other identical molecules
Dissolution
static or slowmoving layers of liquid that surround all
solid surfaces that are surrounded by liquid
that inhibit the movement of solute
molecules from the surface of the solid to
the bulk of the solution
Boundary Layer
Rate of Diffusion
obeys Fick’s Law of Diffusion
Fick’s Law of Diffusion
states that the rate of change in
concentration of dissolved material with time is directly proportional to the concentration difference between the two sides of the diffusion layer
Rate of Dissolution obeys
Noyes-Whitney Equation
Noyes Whitney Equation
the rate of mass transfer of solute
molecules or ions through a static
diffusion layer is directly proportional to
the area available for molecular or ionic
migration, the concentration difference
across the boundary layer; and is
inversely proportional to the thickness of
the boundary layer
Solvents in Liquid Preparations
Alcohol
Diluted Alcohol
Rubbing Alcohol
Glycerin
Glycerol
Propylene Glycol
Purified Water
When are non-aqn solvents used?
Used when drug is insufficiently soluble in aqueous systems or when certain properties, like prolonged release, are desired
How to enhance solubility?
- adjust pH
- cosolvency with glycerol, propylene glycol, ehtanol, low MW PEGs
- complexation with cyclodextrins
- surfactants and micelles, take note cmc and mac
Oral Solutions and preparations
⦿ Dry mixtures for Solutions
⦿ Oral Solutions
⦿ Oral Rehydration Solutions
⦿ Oral Colonic Lavage Solution
⦿ Magnesium Citrate Oral Solution
⦿ Sodium Citrate and Citric Acid Oral Solution
Concentrated aqueous preparations of a
sugar or sugar substitute with or without
flavoring agents and medicinal
substances
Syrup
Components of Syrup
H20, medicinal ,agent, colorant, flavorant, preservatives, sugar
The most frequently employed sugar in syrups
sucrose
Preparation MEthods of Syrup
⚫ Solution of ingredients with the aid of heat
⚫ Solution of ingredients by agitation without the
use of heat or simple admixture
⚫ Addition of sucrose to a prepared medicated
liquid/flavored vehicle
⚫ Percolation of either source of medication or of
the sucrose
Clear, sweetened hydroalcoholic solutions intended for oral use and are usually flavored to enhance their palatability
Elixirs
Less sweet and less viscous to syrup and contains 10 to 12# alcohol
Elixifs
Preparation Methods
Simple solution with agitation. Admixture of 2 more liquid ingredients
Example of Elixirs
Antihistamine
Barbiturate
GHypnotic
Phenobarbital
Digoxin
Alcoholic or hydroalcoholic solutions prepared from vegetable materials or from chemical substances.
⦿ Alcohol content: ranges from 15% - 80%
⦿ Stored in light-resistant containers
Tincutre
Camphorated tincture of
opium
Paregoric with 0.4% opium
Opium Tincutre synonym
Laudanum, more potent 10%
Green Soap Tincture
podofyllin for genital warts
Iodine Tincture
2% I, 2.4% NaI 🡪 NaI3
Compound Benzoin Tincture (protectant)
10% benzoin, 24% aloe, storax, and Tolu balsam
Thimerosal Tincture
⚫ Colored orange red and has greenish fluorescence
⚫ Used for cuts, abrasions, and presurgical antiseptics
It may be defined as aqueous or
oleaginous solutions in the form of
coarse droplets or as finely divided
solids to be applied topically, most
usually to the nasopharyngeal tract or
topically (sunburn, anesthetic, skin
protectant, antipruritic, throat spray,
antifungal).
Sprays
Coal Tar TS
(liqour carbonis detergens,
liquor picis carbonis) - antieczema
dispense in powder or liquid
form to be dissolved in water
Douche
used for irrigative cleansing
vaginnal douche
⚫ Administered rectally for local or systemic absorption.
⚫ Hydrocortisone, aminophylline
Retention enemas
Used to cleanse the bowel
Evacuation Enemas
also known as medicated waters
aromatic waters
clear, aqueous solutions saturated with volatile oils or other
aromatic or volatile substances
Aromatic Waters
aqueous solutions
prepared by diluting the corresponding
concentrated acids with purified water.
Diluted Acids are
liquid preparations composed of pyroxylin dissolved in
solvent mixture usually composed of alcohol and ether with or without added
medicinal substances
Coolodion
Prepared by adding 2% camphor and 3% castor oil
to collodion
Flexible collodion
