Physicochemical Basis of Pharmaceuticals

Description

The Physicochemical Basis of Pharmaceuticals explores the physical and chemical phenomena which affect the formulation and bio-availability of drug substances to give a straightforward, accessible treatment of the essential concepts affecting the absorption and distribution of drugs.

• The ideal primer on the physical and chemical basis of drug design and delivery.
• Focuses on the essential concepts affecting the absorption and distribution of drugs, with full explanations and extensive worked examples to help the reader grasp the concepts presented.
• Offers broad coverage, but at a depth that's perfect for students needing to get a straightforward working understanding of the key issues.
• Unique coverage of dispersal systems and solid state materials, giving a truly rounded coverage of the field.
• Ideal for any student who needs to be aware of physicochemical issues as part of their broader programme of study.

About the Author(s)

Humphrey Moynihan, Department of Chemistry, University College Cork., and Abina Crean, School of Pharmacy, University College Cork.

Table of Contents

1. Pharmaceuticals and medicines
1.1:Introduction to the essential properties of pharmaceuticals
1.1.1:Some key concepts
1.2:Classes of pharmaceutical compounds
1.2.1:Active pharmaceutical ingredients
1.2.2:Excipients
1.3:Drug delivery: getting the active pharmaceutical ingredient to the site of action
1.3.1:Routes of administration
1.3.2:Pharmaceutical dosage forms
1.3.3:Factors influencing dosage form choice
1.4:Summary
2. Pharmaceutical solutions
2.2:Definitions and expressions of solubility
2.1.1:Measurement of solubility and solubility curves
2.2:Solvent structure
2.2.1:Hydrogen bonding and the structure of water
2.2.2:Lipid-based media
2.3:Dissolution and solvation
2.4:Factors affecting solubility
2.4.1:Molecular weight
2.4.2:Hydrogen bonding
2.4.3:Hydrophobic and hydrophilic groups
2.5:Acidity and basicity
2.5.1:pKa and pKb
2.5.2:Acidity and environment
2.6:Salt selection and formation
2.7:Hydrolytic degradation
2.8:Summary
3. Pharmaceutical equilibria
3.1:Essential concepts in thermodynamics
3.1.1:Internal energy, enthalpy and the first law of thermodynamics
3.1.2:Entropy and the second and third laws of thermodynamics
3.1.3:Free energy, chemical potential and equilibrium
3.1.4:Activities of ions in solution
3.2:Phase equilibria
3.2.1:One-component systems and the phase rule
3.2.2:Two-component systems
3.2.3:Osmotic pressure
3.3:Drug delivery: Phase transitions
3.3.1:Diffusion (movement within a phase)
3.3.2:Dissolution (solid -liquid transition)
3.3.3:Partitioning (liquid- liquid transition)
3.3.4:Gas absorption (Gas-liquid phase transition)
3.3.5:Phase transitions during drug delivery
3.4:Summary
4. The pharmaceutical solid phase
4.1:Crystalline and amorphous solids
4.2:The essentials of pharmaceutical crystal structure
4.2.1:Unit cells, crystal systems and lattices
4.2.2:Space groups and space group notation
4.2.3:Crystal planes and faces
4.3:Crystal polymorphism of pharmaceuticals
4.3.1:Relative stabilities of polymorphs
4.3.2:Solvates and hydrates
4.4:Methods of characterising pharmaceutical solids
4.4.1:X-ray diffraction methods
4.4.2:Thermal methods
4.4.3:Other methods of analysis
4.5:Pharmaceutical crystallization
4.5.1:Supersaturation
4.5.2:Nucleation, growth and crystal morphology
4.5.3:Ripening and the rule of stages
4.6:Solid state properties of powder particles
4.6.1:Particle shape
4.6.2:Particle size
4.6.3:Particle surface properties
4.6.4:Gas adsorption
4.6.5:Moisture adsorption
4.6.6:Powder mechanical strength
5. Two phase solid - liquid disperse systems
5.1:Introduction to pharmaceutical disperse systems
5.2:Molecular, colloidal and coarse dispersions
5.3:The physical stability of disperse systems
5.4:Properties of disperse systems
5.4.1:Kinetic properties
5.4.2:Rheology and viscosity
5.4.3:Electrical properties
5.4.4:Interfacial properties
5.4.5:Optical properties
5.5:Suspensions
5.5.1:Nanosuspensions
5.5.2:Coarse suspensions
5.6:Emulsions
5.6.1:Macroemulsions
5.6.2:Multiple emulsions
5.6.3:Microemulsions
5.7:Vesicular systems
5.7.1:Micellar systems
5.7.2:Solubilised systems
5.7.3:Liposomes
5.8:Aerosols
5.9:Foams
5.10:Summary
6. Biological interfaces
6.1:Passive, active and other modes of transport
6.2:Cell membranes
6.3:Partition and partition co-efficients
6.4:Measurement and calculation of partition co-efficients
6.5:Diffusion, diffusion co-efficients and ionisation
6.6:The gastrointestinal barrier
6.7:The blood-brain barrier
6.8:The skin
6.9:Summary
7. Physicochemical aspects of Pharmacokinetics and Pharmacodynamics
7.1:Bioavailability
7.2:Distribution
7.3:Drug target interaction
7.4:Metabolism
7.5:Excretion
7.6:Summary