Simple Solutions Flashcards
a substance, usually a liquid, that dissolves or that is capable of dissolving
the component of a solution that is present in greater amount.
Solvent
the substance being dissolved in the solvent
Solute
ADVANTAGES OF SOLUTIONS
- Complete and rapid Release of active ingredients from formulation.
- Gives the highest bioavailability in general.
- Ease of use.
- Dose is uniform.
- The only type of dosage form that can be given intravenously.
DISADVANTAGES OF SOLUTIONS
- Bulky
- Specialized containers are needed for parenteral products.
- Poor chemical stability
- Difficult to mask foul tasting drugs
- Usually require preservatives
Free from bacteria, impurities, and alike
Common in hospital setting
Sterile Solution
Examples of sterile solutions
Nasal solution
Parenteral
Opthalmic
Irrigation
its contents have not been sterilized, or treated with a process during manufacturing to eliminate potential microorganisms.
Non-sterile solutions
Examples of non-sterile solutions
Aromatic Waters
Elixirs
Spirits
Tinctures
Fluid Extracts
Syrups
refers to the maximum amount of a solute that can be dissolved in an amount of solvent under specific temperature and pressure conditions.
SOLUBILITY
the solubility of an agent in a particular solvent indicates the maximum concentration to which a solution may be prepared with that solvent.
Solvent
A number of medicinal agents provided in a dry powder or granule form
Dry mixture of solution, reconstitution
Reminders for reconstitution
Specified amount of water -> typically purified
typically done to antimicrobials
loosen the powder before mixing
Solutions are typically _________ in nature, has ________
homogeneous, uniformity
Surrounding the solute with solvent particles
SOLVATION
DESCRIPTIVE TERMS OF SOLUBILITY
Very soluble = < 1
Freely soluble = 1 - 10
Soluble = 10 - 30
Sparingly soluble = 30 - 100
Slightly soluble = 100 - 1000
Very slightly soluble = 1000 - 10000
Practically insoluble = > 10000
concentrated solution, no solute can be dissolve
Saturated solution
diluted solution, more solute can be diluted
Unsaturated solution
I2 solubility
2950 ml, Very slightly soluble
Other solvents aside from water:
(i) Alcohol, USP
(ii) Diluted Alcohol, NF
(iii) Rubbing Alcohol
(iv) Glycerin, USP,
(v) Isopropyl Rubbing Alcohol
(vi) Propylene Glycol, USP
(vii) Oil
pH of solvents
Applies to salts
MAJOR FACTORS AFFECTING SOLUBILITY
- Solvent
- Temperature
- pH of the solvent
- The various chemical and other physical properties of both the solute and solvent
- Pressure
- The state of subdivision of the solute -> particle size
- The physical agitation
Weak bases
alkaloids
antihistamines
local anesthetics
Weak acids
barbiturate drugs
sulfonamides
Optimal pH
7.4
The introduction of ____________ into a molecule tends to decrease water solubility because of an increase in the molecular weight of the compound without a proportionate increase in polarity.
halogen atoms
_____________ in the molecular weight of an organic compound without a change in polarity reduces solubility in
water.
Increase
Most pharmaceutical solutions are ___________.
unsaturated with solute
Solutions of this type are prepared by dissolving the solute in a suitable solvent (by stirring or heating).
The solvent may contain other ingredients which stabilize or solubilize the active ingredient.
Simple Solution
These solutions are prepared by reacting two or more solutes with each other in a suitable solvent
Solution by Chemical Reaction
Plant or animal products are prepared by suitable extraction process.
Solution by Extraction
Preparations of this type may be classified as solutions but more often, are classified as ____________
extractives
agents that resist pH change
Buffers
Important for sterile solutions
makes solutions less sensitive
Isotonicity
Used to protect the solutions against microorganisms
Preservatives
Characteristics of a good preservative
Used to protect the solutions against wide spectrum of microorganisms
Stable
Non-toxic and non-senstazing
compatible with other ingredients
free of taste and odor
Examples of acidic preservatives
Benzoic acid
Paraben -> Toxic
Natural -> alcohol
Mercurials -> thimerosal
Example of Basic preservatives
Quaternary Ammonium Compounds
EDTA
ethylenediamine tetraacetic acid
Agents that inhibits oxidation
Antioxidants