ppharm lab

Solubility

What is defined as the concentration of solute in a saturated solution at a certain temperature?

Solubility

What is the spontaneous interaction of two or more substances to form a homogeneous molecular dispersion called?

Nature of solute and solvent

What factor affecting solubility follows the rule “like dissolves like”?

Nature of solute and solvent

polar solutes dissolve in polar solvents and nonpolar

solutes dissolve in nonpolar solvents; “like dissolves like”

polar solvents

Nature of solute and solvent- polar solutes dissolve in _ and nonpolar solutes dissolve in nonpolar solvents; “like dissolves like”

nonpolar solvents

Nature of solute and solvent- polar solutes dissolve in polar solvents and nonpolar solutes dissolve in _; “like dissolves like”

Temperature

higher temperature = greater solubility (solids); solubility of gases decreases with higher temperature

higher

Temperature- _ temperature = greater solubility (solids); solubility of gases decreases with higher temperature

greater

Temperature- higher temperature = _ solubility (solids); solubility of gases decreases with higher temperature

higher

Temperature- higher temperature = greater solubility (solids); solubility of gases decreases with _ temperature

Temperature

What factor affecting solubility states that higher temperature increases solubility of solids but decreases solubility of gases?

Particle size of solute

finer the solute = greater the surface area= more rapid the

dissolving process

finer

Particle size of solute- _ the solute = greater the surface area= more rapid the dissolving process

greater

Particle size of solute- finer the solute = _the surface area= more rapid the dissolving process

rapid

Particle size of solute- finer the solute = greater the surface area= more _ the dissolving process

Particle size of solute

What factor affecting solubility states that finer solute particles dissolve faster due to greater surface area?

Physical agitation

greater the agitation= more unsaturated= more faster the formation

of the solution

greater

Physical agitation- _ the agitation= more unsaturated= more faster the formation of the solution

unsaturated

Physical agitation- greater the agitation= more _= more faster the formation of the solution

faster

Physical agitation- greater the agitation= more unsaturated= more _ the formation of the solution

pH of solvent

ionized drugs dissolve better; unionized forms are less soluble

ionized

pH of solvent- _ drugs dissolve better; unionized forms are less soluble

unionized

pH of solvent- ionized drugs dissolve better; _ forms are less soluble

Pressure

Higher pressure increases the solubility of gases in liquids

Physical agitation

What factor affecting solubility involves stirring or shaking to speed up the dissolving process?

pH of solvent

What factor affecting solubility involves ionization, where ionized drugs dissolve better than unionized forms?

Pressure

What factor affecting solubility is described by Henry’s law, where higher pressure increases gas solubility in liquids?

Co-solvents

What factor affecting solubility involves using substances like ethanol or propylene glycol to enhance solubility?

Complexing agents

What factor affecting solubility involves agents like cyclodextrins or chelators that form complexes to improve solubility?

Polymorphism/Crystalline forms

What factor affecting solubility states that amorphous forms are more soluble than crystalline forms?

Common ion effect

What factor affecting solubility states that the presence of a common ion reduces the solubility of a salt?

Henry’s law

the

solubility of a gas is directly proportional to the pressure of the gas above the liquid

Co-solvents

Substances like ethanol or propylene glycol enhance solubility

Complexing agents

Cyclodextrins or chelators improve solubility by forming complexes

Polymorphism/ Crystalline forms

Amorphous forms are more soluble than

crystalline ones

Common ion effect

The presence of a common ion suppresses the solubility of the

salt

Osmosis

What is the diffusion or movement of solvent molecules through a semi-permeable membrane from a region of higher solvent concentration to a region of lower solvent concentration?

Osmotic pressure

What is the pressure responsible for osmosis and its prevention?

TONICITY

is a measure of the osmotic pressure of two solutions

separated by a semi-permeable membrane.

higher solvent concentration

to a region of lower solvent concentration

movement of conc in osmosis

ISOTONIC SOLUTION

Solution that has the same osmotic

pressure as the body fluid or 0.9% NaCl

HYPOTONIC SOLUTION (0.5%)

Solution that has lower osmotic pressure

than the body fluid or 0.9% NaCl

HYPERTONIC SOLUTION (1.0%)

Solution that has a higher osmotic pressure

than the body fluid or 0.9% NaCl

isotonic soln

hypotonic soln

hypertonic soln

hypotonic soln

Causes swelling and

bursting of RBC

isotonic soln

No changes in RBC size

hypertonic soln

Causes crenation and

shrinkage of RBC

hypotonic soln

isotonic soln

hypertonic soln

Blood, eye, nasal tract, and other body fluids

With what body fluids or areas are isotonic solutions commonly used?

No swelling, no contraction, no discomfort

What happens to tissues when they come in contact with isotonic solutions?

Class 1

Addition of NaCl

Class 2

Addition of Water

Class I- Addition of NaCl

A. Sodium Chloride Equivalent

B. Cryoscopic Method

C. Freezing Point Depression

Class II- Addition of Water

A. Sprout’s Method

B. White Vincent Method

The number of particles of solute in solution

What does the osmotic pressure of an electrolyte depend on in relation to solute particles?

i

What is the symbol for the dissociation factor used in calculating osmotic pressure?

By dividing the total number of particles (undissociated molecules + ions) in a solution by the number of particles before dissociation

How is the dissociation factor (i) calculated?

Sodium chloride equivalent (E)

What is defined as the weight of sodium chloride that will produce the same osmotic effect as 1g of a drug?

Water movement in and out of the cell is the same, and RBCs remain unchanged

What happens to red blood cells in an isotonic solution?

RBCs swell and burst

What happens to red blood cells in an iso-osmotic solution?

Viscosity (n) “ eta”

◦Internal friction or resistance of fluid to flow

resistance

Viscosity (n) “ eta” - Increase viscosity = increase _

Viscosity (n) “ eta”

◦Increase viscosity = increase resistance

viscosity

Viscosity (n) “ eta” - Increase _ = increase resistance

Resistance to flow increases.

What happens to flow when viscosity increases?

dyn·s/cm², poise, or g/(cm·s)

What are the units of viscosity?

Viscosity (n) “ eta” units

Units: dynes x sec/ cm2

, poise, g/ cm x sec

n

shear stress/ rate of shear

n= shear stress/ rate of shear

What is the formula for viscosity?

Shear Stress (t) “tau”

It is a measure of the force of friction from a fluid acting on a body in the path of that fluid.

Shear rate

It is the rate of change of velocity at which one layer of fluid

passes over an adjacent layer

rate if shear

shear stress

viscosity

factor affecting _ determination:
temperature = increasing temp - decreasing viscosity (inverse)

temperature

factor affecting viscosity determination:
_ = increasing temp - decreasing viscosity (inverse)

increasing

factor affecting viscosity determination:
temperature = _ temp - decreasing viscosity (inverse)

decreasing

factor affecting viscosity determination:
temperature = increasing temp - _ viscosity (inverse)

inverse

factor affecting viscosity determination:
temperature = increasing temp - decreasing viscosity (_)

Rheology

a branch of physics that deals with the deformation & flow

of matter

Newtonian flow

Non-Newtonian flow

Classification of Material according to type of flow: 2

Newtonian flow

Follows the Newtonian law of direct proportionality between shearing stress & rate of shear

Newtonian flow

Characterized by a constant viscosity regardless of the shear stress applied

Newtonian flow

castor oil

Newtonian flow

chloroform

Newtonian flow

ethanol

Newtonian flow

water

Newtonian flow

olive oil

Non-Newtonian flow

characterized by the change in viscosity

with increasing rate of shear

Plastic flow or Bingham body

Pseudoplastic flow

Dilatant flow

Classification of Non-Newtonian material 3

Plastic flow or Bingham body

Yield value/ yield stress must be applied to cause them flow

Plastic flow or Bingham body

Behavior: plasticity

Plastic flow or Bingham body

Characteristics: flocculated particles in concentration by suspension

Plastic flow or Bingham body

cerates

Plastic flow or Bingham body

cataplasm

Plastic flow or Bingham body

cream

Plastic flow or Bingham body

ointment