Ceutics Final Flashcards
Electrolyte
Ability to ionize and conduct electricity
Non-Electrolyte
Do not ionize or conduct electricity
Strong electrolyte
substance that completely dissolves in water
Weak electrolyte
Molecule that partially ionize in water
when is a drug 50% ionized and 50% unionized
pH = pKa
LADME
Liberation, Absorption, Distribution, Metabolism, Excretion
Physicochemical properties that affect a drug after administration
Solid State Properties Ionization Solubility and Dissolution Partition Coefficient Mass Transport and Membrane Passage
Drug Development and approval process
Discovery -> Pre-Clinical -> IND -> FDA Review -> Clinical -> NDA/BLA Pre-Approval inspection -> FDA Response
FDA and USP roles
USP - Sets standards
FDA - Enforces the standards
Examples of Chemical Instability
Hydrolysis, Oxidation, Maillard Reaction, Photolysis
Examples of Physical Instability
Change between two crystalline forms or conformational changes in proteins
Solid State Degradation steps
- Loosening of molecules at the reaction site
- Bond breaking and making
- Solid solution formation of the degradation product
- Separation and crystallization of the degradation product within the parent solid
Colligative Properites of Solutions
Lower Vapor Pressure
Increase in Boiling Point
Decrease Freezing Point
Establishes Osmotic Pressure of Solvent by Solute
Intrinsic Solubility
Equilibrium solubility of the free acid or base form of an ionizable compound at a pH where it is fully unionized
Dissolution
Process by which molecules leave the solid phase and enter into solution
Partition Coefficient
Ratio of concentrations of a compound in the two phases of a mixture of two liquids that can’t undergo mixing at equilibrium
Apparent Partition Coefficient
Equal to the partition coefficient when the drug is completely unionized, it is a ratio of concentrations of ONLY unionized species
Passive Transport
Movement of biochemicals and other atomic or molecular substances across cell membranes without need of energy input
Active Transport
Movement of biochemicals across a cell membrane in the direction against some gradient or other obstructing factor
Facilitated Diffusion
Passive-Mediated Transport, process of spontaneous passive transport of molecules or ions across a biological membrane via specific transmembrane integral proteins
Permeability Coefficient
associated with simple diffusion through a membrane that is proportional to the partition coefficient and the diffusion coefficient and inversely proportional to the membrane thickness
Absorption Factors
Concentration of Drug Molecular Weight of molecule Partition coefficient (10-100 optimal) Ionization State Surface Area of Site Blood flow to that region
Coordinated Complexes
Metal Complexes, covalent bonds
Molecular Complexes
Noncovalent bonds
