Ceutics Flashcards
What will you come to know about in this chapter?
Solubility expression, mechanisms of solute-solvent interaction, ideal solubility parameters, solvation and association, factors influencing drug solubility, diffusion principles in biological systems
These objectives guide the learning outcomes of the chapter.
What are the main aspects of solubility discussed in this chapter?
Solubility of gas in liquids, liquids in liquids, Raoult’s Law, critical solutions temperature (CST), distribution law
These aspects cover both theoretical and practical applications of solubility.
What is Raoult’s Law?
A principle that relates the vapor pressure of a solvent to the concentration of solute
It applies to ideal solutions and is essential for understanding solubility in mixtures.
What does the Critical Solutions Temperature (CST) indicate?
The temperature at which two components of a mixture become completely miscible
CST is crucial in understanding solubility behavior in various temperatures.
What is the Distribution Law or Nernst’s distribution law?
A law that describes how a solute distributes itself between two immiscible solvents
It has applications in extraction processes and limitations in certain conditions.
Fill in the blank: Factors influencing the _______ of drugs are discussed in this chapter.
[solubility]
What are the mechanisms of solute-solvent interaction?
Interactions such as hydrogen bonding, van der Waals forces, and ionic interactions
These interactions play a critical role in determining solubility.
What is meant by ‘ideal solubility parameters’?
Quantitative measures that predict how well a solute will dissolve in a solvent
They help in formulating drugs and understanding solubility.
What are the principles of diffusion in biological systems?
The movement of molecules from an area of higher concentration to an area of lower concentration
This principle is essential for drug delivery and absorption.
What types of solubility are explored in this chapter?
Solubility of gas in liquids, liquids in liquids
Each type has unique characteristics and applications.
What are the applications of Distribution Law?
Used in extraction processes, drug formulation, and pharmacokinetics
Understanding these applications is vital for practical uses in chemistry and pharmacology.
What are the limitations of Distribution Law?
Assumes ideal behavior, may not apply to highly polar or ionic compounds
Recognizing these limitations is important for accurate predictions in real-world scenarios.
What is solubility defined as in quantitative terms?
The concentration of solute in a saturated solution at a particular temperature
How can solubility be qualitatively defined?
The spontaneous interaction of two or more substances to form a homogeneous molecular dispersion
What factors affect the solubility of a solute?
- Physical and chemical properties of solute and solvent
- Temperature
- Pressure
- pH of the solution
- Particle size of the solute
Why is understanding solubility important for pharmacists?
It is a key parameter affecting the formulation of dosage forms
What are some phenomena that make solubility an important criterion?
- Choice of solvent for liquid formulation
- Dissolution of drugs
- Bioavailability of drugs
What is a solution?
A system in which solutes are completely dissolved in solvent and remain present at the molecular size
Define solute.
The substance which is dissolved in the solvent
Define solvent.
The component in which solute is dissolved
What is a saturated solution?
A solution in which solute is dissolved up to its maximum limit of solubility at a given temperature and pressure
What is an unsaturated solution?
A solution in which dissolved solute is in a concentration below the required amount necessary for complete saturation
What is a supersaturated solution?
A solution which contains more of the dissolved solute than it would normally contain in a saturated state
How is solubility expressed according to the United States Pharmacopeia (USP)?
As parts of solvent required for one part solute
