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Drug Delivery Systems II
DDS exam one
87
Other
Professional
02/19/2008

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Term
the speed of a reaction is propotional to a paramater called the
Definition
rate constant (k)
Term
Energy necessary for the reaction to take place. can be reduced by catalyst
Definition
Enery of Activation (Ea)
Term
units of rate constants for first order kinetics
Definition
1/h
Term
The study of drug stability under stress factors
Definition
Accelerated stability testing
Term
(T/F) Increase in temperature results in faster degradation rates of drugs
Definition
True
Term
quick estimate of drug stabilities
Definition
Q10 factor
Term
the speed of many chemical reactions increases by ____to_____ times with 10 degrees Celsius rise in temperature
Definition
2 to 4
Term
The average Q10 for most drug degradations, can be used to do quick estimates of drug shelf lives.
Definition
Q10=3
Term
(T/F) shelf life decreases as temperature decreases
Definition
False-shelf life INCREASES as temperature decreases
Term
substance that increases the rate of a reaction with changing itself, decreases Ea subsequently increasing the rate constant
Definition
catalyst
Term
T/F Many drugs in aqueous solution degrade faster because of the presence of water.
Definition
True
Term
When H30+ ions participate in the drug degradation, also has a slope of -1 in a plot of logk vs. pH.
Definition
specifc acid catalysis
Term
When OH- ions participate in the drug degradation process, a plot of logk vs pH has a slope of 1.
Definition
Specific Base Catalysis
Term
When H2O molecules participate in the drug degradation process.
Definition
Solvent Catalysis
Term
When HA (Acid form) of buffer substance in aqueous solutions participates in drug degradation. Slope is not equal to 1 in a graph of logk vs. pH
Definition
General Acid Catalysis
Term
When A- (base form) of buffer substance in aqueous solutions participates in the drug degradation process. slope is not equal to 1 in a graph of logk vs. pH
Definition
General Base Catalysis
Term
Stability is highest when the rate constant (k) is __________
Definition
lowest
Term
T/F Light enery can not provide the energy of activation
Definition
FALSE, it can
Term
The cause of many photochemical drug degradations
Definition
UV Light
Term
________________ containers are used to protect drug substances from photodegradation
Definition
Colored Glass
Term
Color that gives best protection from UV light
Definition
Yellow-Green
Term
Gives reasonable protection from UV light but not much against infrared light
Definition
Amber
Term
Which form is generally more pharmacologically active, D (dextro) or L (levo)
Definition
L (levo)
Term
Racemization usually follows _______ _________ kinetics
Definition
first order
Term
Drugs containing _________ groups usually undergo hydrolysis.
Definition
ester
Term
Most drugs have greater stabilities in pH of
Definition
3 to 4
Term
T/F OH- ions have greater catalytic effect than H3O+ ions
Definition
True
Term
may be added to reduce minor changes in pH that would induce significant degradation of the active ingredient
Definition
Buffers
Term
Major cause of product instability
Definition
Oxidation
Term
used by drug companies to displace air from containers to avoid oxidation of drug formulations
Definition
Nitrogen and Carbon Dioxide
Term
T/F Decreases in temperature accelerate the rate of oxidation
Definition
False, INCREASES in temperature accelerate the rate of oxidation
Term
Oxidation rates may be affected by:
Definition
Temperature, Radiation, and Catalyst
Term
T/F Trace amounts of heavy metals will prevent oxidation of drug products.
Definition
False, trace amounts of heavy metals will CATALYZE oxidation of drug products ex: cupric, chromic, ferrous, ferric ions)
Term
used to sequester metal ions
Definition
chelating agents
Term
Ions that catalyze oxidation reactions
Definition
H30+ and OH-
Term
Useful in increasing the stability of drug formulations undergoing chain reaction mediated oxidation
Definition
Antioxidants, ex: for aqueous ascorbic acid, sodium sulfite, and thiosulfate for oil: ascorbyl palmitate, hydroquinone, and alpha-tocopherol
Term
T/F Reductions are less common than oxidation
Definition
True
Term
how "non-changing" and drug products remains over a given length of time
Definition
Drug Product Stability
Term
Five types of stability that must be considered for drug products
Definition
1. Chemical
2. Physcial
3. Microbiological
4. Therapeutic
5. Toxicological
(CPMTT)
Term
Time the formulation remains within the desired potency and integrity when stored at recommended conditions.
Definition
Expiration date
Term
can be redispersed homogenously with moderate shaking and can be poured easily throught its shelf life, Crystal form, partical size, and physiological availability should be maintained throughout its shelf life
Definition
Suspension
Term
resdispersed homogenously to its orginal state with moderate shaking, gross physical stability should be maintained
Definition
Emulsion
Term
Clarity, Color, and Odor are retained throughout its shelf life
Definition
Solutions
Term
Retain their origianl size, shape, weight, and color throughout their shelf life.
Definition
Tablets
Term
Should not soften, stick, harden, or crack throughout shelf life. should remain microbiologically uncontaminated over time
Definition
Gelatin Capsule
Term
High viscosity suspension that should maintain consistency throughout shelf life.
Definition
Ointments
Term
The active ingredient in formulation has a potency less than pre-established goal, usually 90% of original potency
Definition
Potency Loss
Term
Overtime a toxic degradation byproduct may form at unacceptable levels
Definition
Toxicity Development
Term
Most common solvent in pharmaceutical work
Definition
water
Term
Concentration of the solute in equilibrium with undissolved solute in a given solvent and temperature, the maximum extent to which solute can dissolve
Definition
Solubility
Term
T/F Drug must be in solution before it can be absorbed and exert therapeutic action
Definition
True
Term
solute and solvent showed a SPONTANEOUS reaction to form a homogenous mixture such that nor more solute can be mixed with solvent.
Definition
Saturated Solution
Term
solute and solvent showed a SPONTANEOUS reaction to form a homogenous mixture such that more solute can be mixed with the solvent
Definition
Unsaturated Solution
Term
Solute and Solvent showed a NONSPONTANEOUS reaction to form homogenous mixture such that solute concentration exceeds solubility
Definition
Super saturated solution
Term
Molarity
Definition
moles of solute in 1L solution
Term
Molality
Definition
Moles of solute in 1kg solvent
Term
Normality
Definition
gram-equivalent weight of solute in 1L solution
Term
Mole fraction
Definition
moles of solute per solution total number of moles
Term
concentration of dissolved gas in equilibrium with gas above the the solution.
Definition
Solubility of gas in liquid
Term
Solubility of gas ___________ as pressure above the solution increases
Definition
increases
Term
As temperature increases, the solubility of most gases __________.
Definition
decreases
Term
Addition of salts to dissolved gas solutions results in _________ gas solubility
Definition
decreasing, because the added salts compete for solvent molecules and mroe gas is released from the solution
Term
Gases that react with solvent ___________ their solubility
Definition
increase, ex: HCl gas, ammonia, CO2
Term
___________ miscibility is seen when liquids mix in all prportions
Definition
Full
Term
______________ miscibility: where completely dissolved solutions are seen only at certain temperatures and compositions.
Definition
Partial
Term
_________ solutions, solubility depends on heat of fusion and the melting point of the solute.
Definition
Ideal
Term
Solutes and Solvents in Ideal Solutions are __________ chemicals
Definition
nonpolar
Term
example of ideal solution
Definition
naphthalene dissolved in benzene or toluene
Term
___________ solutions also account for complexation, hydrogen bonding, and ionization
Definition
Nonideal
Term
Most pharmaceutical solutions are
Definition
nonideal
Term
occurs when solute reacts with another substance in the solution to form a complex. Can either increase or decrease solubility
Definition
Complexation
Term
Compounds with what functional groups can form hydrogen bonds with water, thereby increasing solubility
Definition
OH, NH, SH
Term
T/F Aqueous solubility decreases with solute increase in carbon chains
Definition
True
Term
T/F The lower the melting point the lower the aqueous solubility
Definition
False, the HIGHER the melting point, the lower the aqueous solubility
Term
Chain branching of hydrophobic groups _________ aqueous solubility
Definition
increases
Term
T/F Hydrophilic substituents increase aqueous solubility
Definition
True
Term
Solubility of solute is increased when salt is added
Definition
Salting In
Term
Solubility of solute is decreased when salt is added
Definition
Salting Out
Term
Compounds which dissociate to a small extent in water
Definition
Sparingly soluble salts
Term
When a common ion is added to a solution of sparingly soluble salt, the solubility is affected
Definition
Common Ion Effect
Term
endothermic system, ∆Hsol is ____________. solubility __________with increasing temperature
Definition
positive, increases
Term
Exothermic solution: ∆Hsol is ___________, solubility _________ with increasing temperature
Definition
negative, decreases
Term
No change in the system heat: ∆Hsol is ____________ and the solubility is _____ _____________
Definition
zero, NOT affected
Term
T/F ionized weak acids and bases have theoretically very high solubilities
Definition
True
Term
Acids are more soluble at _____pH
Definition
High (alkaline)
Term
Bases are more soluble at ______pH
Definition
Low (acidic)
Term
T/F solubility of strong electrolytes generally decreases as dielectric constant and/or polarity of solvent decrease
Definition
True
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