Integrated Physical Pharmacy & Pharmaceutics- I Lecture Notes

Comprehensive vocabulary flashcards covering the Integrated Physical Pharmacy & Pharmaceutics- I course syllabus, including units on excipients, phase equilibria, interfacial phenomena, solubility, solutions, rheology, emulsions, suspensions, and colloids.

Pharmaceutics

A branch of pharmacy concerned with the scientific and technological aspects of design and development of dosage forms, including formulation, manufacture, stability, and effectiveness.

Physical Pharmacy

A discipline in pharmacy concerned with the physicochemical properties of pharmaceutical ingredients.

Dosage Forms

Drug delivery systems designed to deliver active ingredients to the body at a rate and amount that assures the desired pharmacological effect and therapeutic response.

Pharmaceutical Excipients

Inactive or inert ingredients, other than the active drug, used to convert pharmacologically active compounds into dosage forms suitable for administration.

Specific Surface Area

The surface area per unit weight of powder, which increases as particles become more finely divided.

Partition Coefficient (PC or P)

A measure of the lipophilic character of a drug, defined by the formula $P = \frac{[\text{drug conc. in octanol}]}{[\text{drug conc. in water}]}$.

Log P

The logarithm of the partition coefficient; if $\text{Log } P > 0$, the drug is lipid soluble; if $\text{Log } P < 0$, it is water soluble; and if $\text{Log } P = 0$, there is equal distribution.

Polymorphism

The existence of a drug substance in different crystal forms, where one is stable and the others are metastable, exhibiting the same chemical but different physical properties.

Purified Water

Water subjected to purification (e.g., distillation, demineralization) used for topical and oral dosage form preparations.

Water for Injection (WFI)

Purified water subjected to steam distillation or reverse osmosis; it is free from pyrogens and particulate matter but is not necessarily sterile.

Preservatives

Compounds used to inhibit microbial-triggered pharmaceuticals instability, such as Benzoic acid or Phenol, which act by denaturing proteins or lysing cytoplasmic membranes.

Antioxidants - Reducing Agents

Substances that have a lower redox potential than the drug and are preferentially oxidized, such as Ascorbic acid, Sodium metabisulfite, and Sodium bisulfite.

True Antioxidants

Agents that act by a chain termination mechanism by reacting with free radicals, such as Butylated hydroxytoluene (BHT) and Butylated hydroxyanisole (BHA).

Buffer Solution

A solution containing a weak acid and its conjugate base (or a weak base and its conjugate acid) that maintains an approximately equal pH value when small amounts of acidic or basic substances are added.

Surfactants (Surface-Active Agents)

Amphipathic substances that adsorb onto interfaces to alter surface or interfacial tension and free energy, possessing both hydrophilic and hydrophobic regions.

HLB (Hydrophile-Lipophile Balance)

An arbitrary scale system (0 to 20) used as a measure of the balance between the hydrophilic and lipophilic regions of a surfactant.

London Forces

Induced dipole-induced dipole interactions present in all molecules, resulting from attractions between an instantaneously induced dipole and another induced dipole.

Keesom Forces

Dipole-dipole interaction forces existing in polar molecules that have permanent dipoles, resulting in an orientation effect.

Gibbs Phase Rule Equation

The relationship between degrees of freedom ($F$), components ($C$), and phases ($P$) expressed as $F = C - P + 2$.

Degrees of Freedom (F)

The minimum number of independent variable factors (temperature, pressure, and concentration) that must be fixed to define the condition of a system completely.

Eutectic Mixture

A mixture of components that do not form a new chemical compound but, at certain ratios, inhibit crystallization resulting in a melting point lower than any of the pure components.

Surface Tension ($\gamma$)

The net inward force per unit length (dyne/cm) that molecules at the surface exert on molecules in the bulk to decrease surface area.

Surface Free Energy (W)

The minimum amount of work required to expand a surface by unit area, calculated as W = \text{\gamma} \times \text{\Delta A}.

Spreading Coefficient (S)

An assessment of a liquid's ability to spread over another, defined as $S = W_a - W_c$ or S = \text{\gamma}_S - (\text{\gamma}_{LS} + \text{\gamma}_L), where spreading occurs if $S$ is zero or positive.

Henry’s Law

The principle that the solubility of a gas in a liquid is proportional to its vapor pressure above the solution, expressed as \text{\sigma} P = C_2.

Salting Out

The phenomenon where the introduction of an electrolyte (like NaCl) or non-electrolyte (like sucrose) decreases the solubility of gas and causes its liberation from the solvent.

Syrups

Sweet, viscous, and concentrated aqueous solutions containing sucrose at concentrations of $65\% \text{ w/w}$ or $85\% \text{ w/v}$.

Elixirs

Clear, brilliant, sweetened, flavored, and preserved hydro-alcoholic solutions containing more alcohol and less sugar than syrups.

Rheology

The science of flow or deformation of pharmaceutical materials under stress.

Newtonian Fluid

A fluid where the shearing stress ($F/A$) is directly proportional to the shear rate ($dv/dx$), as defined by \frac{F}{A} = \text{\eta} \frac{dv}{dx}.

Pseudoplastic Flow

A type of non-Newtonian flow known as 'shear-thinning,' where viscosity decreases as the shear rate increases.

Thixotropy

A reversible gel-sol transformation where a fluid undergoes a decrease in viscosity over time during constant shearing.

Emulsion

A disperse system consisting of two immiscible liquid phases (oil and water) stabilized by an emulsifying agent.

Stokes' Law

Defines the velocity of creaming or sedimentation ($v$) as v = \frac{2r^2 g (\text{\sigma} - \text{\rho})}{9 \text{\eta}}, where $r$ is globule radius and \text{\eta} is viscosity.

Suspension

A coarse dispersion where insoluble drug particles (suspensoids) are dispersed throughout a liquid vehicle.

Zeta Potential

The electrical potential at the shear plane of a particle; high values indicate repulsive forces dominate, leading to a deflocculated system.

Sedimentation Volume (F)

The ratio of the volume of sediment ($V_s$) to the initial volume of suspension ($V_i$), expressed as $F = \frac{V_s}{V_i}$.

Lyophilic Colloids

Thermodynamically stable 'solvent-loving' colloids that form spontaneously when solutes interact with the solvent.

Tyndall Effect

The light scattering effect observed when a beam of light passes through a colloidal solution, making the sol appear turbid.

Liposomes

Artificial lipid vesicles consisting of one or more lipid bilayers enclosing aqueous compartments for drug entrapment.