T1 - Final Exam: New Material Flashcards
What is a homogenous dispersion?
A molecular dispersion
What is a heterogenous dispersion?
The dispersed phase (usually a particle of some type) is physically distinguishable from the dispersion medium
What is the components of a dispersion?
- Dispersed phase
- Dispersion media
What is dispersed phase?
The internal or continuous phase of a dispersion
What is the dispersion media?
External or continuous phases of a dispersion
How are dispersions classified?
- Phase
- Particle size
What are the dispersions of solid phases?
- Suppositories and medicaition sticks
- Gels
- Solid form
What are the dispersions of liquid phases?
- Crystal suspensions
- Emulsions
- Foams
What are the dispersions of gas phases?
- Smoke, aerosols, spray powder, inhalation dry powder
- Mist, unevaporated liquid sprays
What are the phase categories of dispersions?
- Solid
- Liquid
- Gas
What are the particle size categories of dispersions?
Colloidal dispersion (0.1 – 1000 nm)
Coarse dispersion (1 -200 micrometer)
What are the colloidal dispersion types?
- Lyophillic
- Lyophobic
- Association
What does it mean to be lyophilic?
- Solute has a strong affinity for medium
- Has polar regions from ionizable functional groups
How does having a polar region affect lyophilic colloids?
Enables hydration in aqueous environments
What are examples of lyophilic colloids?
- Proteins: albumin, gelatin
- Polysaccharides: natural gums, cellulose derivatives
What is a colloidal solution?
Macromolecular dispersions that are solvated by the medium
What is crystalloid solution?
Small molecule dispersion that are solvated by the medium
What states are hydrophilic colloids found in?
Solid or gel state
What is the difference between a sol and gel state?
In sol state, molecules move freely in solution
In gel state, molecules form connected networks resulting in increased viscosity
What is lyophobic?
Compounds lack polar groups to give them surface hydrophilicity
What are examples of lyophobic colloids?
Milk, lipid emulsions, nanocrystal suspensions
What is the problem of having hydrophobic colloids?
Tendency to aggregate
What is the predominate plasma protein?
Albumin
What is association colloid?
Formed by association of dissolved particles into a substance in the colloidal size range.
How does physiologic colloids maintain fluid balance in the body through hydrostatic pressure?
capillary hydrostatic pressure
What are examples of association colloids?
- Surfactant micelles
- Liposomes
What is a microemulsions?
Dispersion of oil-in-water or water-in-oil that is smaller than conventional emulsions
Thermodynamically favorable
What is CHP?
- Pressure exerted by blood against the wall of a capillary
- Drives the force that drives fluid out of capillaries to tissues
- As fluid exits a capillary and moves into tissues, the hydrostatic pressure in the interstitial fluid correspondingly rises
How does physiologic colloids maintain fluid balance in the body through colloidal oncotic pressure?
- Form of osmotic pressure induced by the proteins, notably albumin, in a blood vessel’s plasma (blood/liquid) that displaces water molecules
- Opposing effect of both hydrostatic blood pressure pushing water and small molecules out of the blood into the interstitial spaces within the arterial end of capillaries and interstitial colloidal osmotic pressure
What effect will administering hypertonic have on intracellular and extracellular volume?
Administering hypertonic solution will increase extracellular volume and decrease intracellular volume
What effect will administering hyportonic have on intracellular and extracellular volume?
Administering hypotonic solutions will increase both extracellular and intracellular volume
What effect will administering isotonic have on intracellular and extracellular volume?
Administering isotonic solutions will increase extracellular volume while not affecting intracellular volume
What effect will administering colloidal dispersions have on intravascular, interstitial and intracellular volume?
Administering colloidal dispersions will increase the intravascular volume and not intracellular or interstitial volume
What are the 3 association colloids?
- Surfactant micelle
- Microemulsions
- Liposome
What are surfactant micelles?
Form spontaneously when CMC is reached 2-5 nm
What is a liposome?
More complex bilayer structures 50-100 nm may become large enough to exceed colloidal size range
What is Brownian motion?
Random, irregular movement of particles
What causes Brownian motion?
Bombardment of particles by the molecules of the dispersion media
What is particle movement affected by?
- Particle size
- Viscosity of medium
- Temperature
What are the major factors affecting distribution uniformity
- Brownian motion
- Gravitational forces
- Dispersion particle growth
What does bombardment by medium molecules?
- The higher the energy, the more particle movement is observed.
- Brownian motion stops at Absolute Zero
What decreases the effect of Brownian motion?
- Decrease temp
- Increase viscosity
- Increase particle size
What are colloidal particles?
- Particles are small enough that Brownian Motion keeps particles suspended
- Unique to colloidal dispersion
- Can counteract gravitational forces
How are colloidal aggregates affected by gravitational forces?
Behave in a predictable manner
How would particles sediment according to Stokes Law?
- Course dispersion like suspensions will sediment down
- Oil and water emulsion will sediment up (creaming)
Describe the rate of sedimentation?
- Inversely related to viscosity
- Proportional to density and particle diameter
What is aggregation?
- Particles tend to aggregate together
- Both reversibly and irreversibly
What occurs in a coarse dispersion like suspension or emulsion?
- Molecules at the interface between the particle and the dispersion media are subject to different forces than those molecules within the particle.
- The interfacial molecules will have lower binding energy with interior molecules
- The result of this is a positive surface energy.
- Magnitude of the surface energy depends on the collective cohesive and adhesive forces within a particular system
What occurs when particle size is reduced?
- Surface area is increased
- More molecules are in contact with dispersion media
- Free surface energy rises
- Result is aggregation and dispersion stability is impaired
What causes aggregation to occur or not occur?
Forces surrounding particle interactions
What is the DVLO theory?
2 primary forces that determine whether aggregation in a suspension
What are the 2 potentials of DVLO theory?
- Van der Waals attraction
- Electrostatic repulsion
Describe how Van der Waals and Electrostatic potential can affect aggregation
- Both potentials occur simultaneously to differing degrees within a system
- Each potential approaches zero as distance between particles increases
- Which positive or negative predominate will determine whether aggregation occurs
What are the Non-DVLO forces?
- Hydration
- Steric
What occurs during a hydration force?
- Occurs with hydrophilic colloids
- Water molecules may interact and get much closer than electrostatic forces while competing with van der Waals forces.
- The net result is repulsion which keeps the colloidal particles apart
What occurs during a steric forces?
- Coating of particles with polymeric materials
- Creates a physical barrier which prevents van der Waals attractive forces
What is Ostwald ripening?
Creation of large particles at the expense of smaller ones
According to Ostwald ripening, what happens when particles are added to a solution?
- Smaller particles will undergo dissolution faster the larger particles
- As this occurs, the solutes from smaller particles diffuse toward and deposit on larger particles.
- Growth in particle size results
- As dissolution progresses, the smaller particles continue to get smaller perpetuating the large particle growth.
- Any effect that increases dissolution will increase this ripening.
What is van de waal forces?
- Attractive forces between molecules created from fluctuations in electron density.
- Creates dipole-induced dipole interactions
- These are weak between individual molecules
- With particles, however, the collective forces can create a strong attraction
What is electrostatic forces?
- Depend on the magnitude of surface charge
- Magnitude of surface charge comes from:
Ionizable groups on particle molecules
Adsorption of ions from solution onto uncharged particle surface
What is a shear plane?
Boundary between the diffuse layer and the dispersion medium surrounding the particle
What is difference between the stem and diffuse layer?
- Stem: when particles within the medium, counterions bound
- Dif: Fraction of the ions stay with the particle
What happens to weak bound ions the diffuse layer?
Pulled away with particle movement
What is zeta potential?
The net electric charge at the outer diffuse layer the occurs at the shear plane
What happens if there is an increase in zeta potential?
The more repulsion (electrostatic potential) between particles is present
Describe the magnitudes of particle interactions
Van der Waal is attractive potential that is represented negatively
Electrostatic repulsive potential have positive value
What do the curve of particle interactions represent?
The strength of the attraction as particles come closer together
How is net interaction potential curve produced?
Subtracting the repulsive and attractive potentials as a given distance
What is the difference between net interaction energy and primary minimum?
Net: Positive repulsive energy barrier (electrical repulsion dominates) must be overcome
Prim: As particles get closer, the negative and strong van der Waals attractive potential can create an energy trap
How can salts alter potential energy?
- Add counter ions to the diffuse layer
- Reduce repulsion
- Charge neutralization is closer to the particle
- Van der Waals can become more dominant at distance creating a weak secondary minimum
- Particles weakly coming together to form floccules which are easily resuspended
What are the properties of the flocculated suspensions?
- A suspension in which particles have undergone flocculation
- Has floccules
- The rate of sedimentation is high
- The volume of sediment is high
- Form porous sediments
- The redispersion of sediment can easily by done by agitation
What plays a significant role on adsorption?
Electrical charges on both the solid adsorbent and liquid absorbate
What is responsible for physical adsorption from solution onto the solids?
Hydrogen bonds and van der waals forces that are weak attractive forces
What is responsible to chemisorption?
Ion exchange and other strong attractive forces
What is the relationship between solubility and adsorption?
- Inversely related
- The lower solubility the higher the adsorption
What is the relationship between adsorption and pH?
- Affects the degree of ionization of the drug and its solubility
- Unionized forms will be more adsorbent than ionized species
What is relationship between adsorption and temperature?
Adsorption is an exothermic process, therefore decreasing temp will enhance the adsorption process
What are floccules?
Form loose agglomerations of particles
What is rheology?
The study of flow, addresses the viscosity characteristics of powders, fluids, and semisolids
How does surface area affect adsorbent?
The smaller the particle size or the more porous the solid, the higher the capacity of adsorption
What adsorbents absorb more effectively to non polar compounds?
Non polar
What is an amphiphile?
Have both hydrophobic and lipophilic portions of their molecules
What are examples of zwitterionic surfactants?
Phospholipids
What is the use of zwitterionic surfactants?
Co-surfactant to boost foaming properties
How does pH affect zwitterionic surfactants?
Depending on pH their, they can be anionic, cationic, or zwitterionic
What are examples of non-ionic surfactants?
- Polyoxyethylene alkyl ethers
- Fatty acid alkanolamides
- SPAN
- TWEEN
- Alkyl polyglucoside
Wh at is the use of polyoxyethylene alkyl ethers?
Pharmaceutical cosmetics
What is the use of fatty acid alkanolamides?
Foam stabilizers and viscosity enhancers
What is the use of SPAN?
- Water in oil emulsion
- Combined with TWEENs is pharmaceutical, cosmetics, and food
What is the use of TWEEN?
Oil in water emulsion combined with SPAN
What is alkyl polyglucosides?
Dishwashing detergent and shampoos
What are the incompatibilities of non-ionic surfactants?
None
How does pH affect non-ionic surfactants?
Not affected by presence of salts or by pH
What are examples of cationic surfactants?
- Alkylbenzyldimethyl ammonium salts
- Akyltrimethyl ammonium salts
What is the use of cationic surfactants?
- Bacteriodical
- Adsorb to negatively charged surfaces
- Fabric sofeners
- Hair conditioners
What are the incompatibilities of cationic surfactants?
Anionic surfactants
What is compatible with cationic surfactants?
Non-ionic and zwitterion surfactants
What are examples of anionic surfactants?
- Na/K
- Sulfates
- Sulfonates
- N-Acyl taurines
- Monoalkyl phosphates
- Acyl Isethionates
- N-acyl sarcocinates
What is the use of Na/K salts of chain fatty acids?
Use above pH7
What is the use of sulfates?
- Toothpaste
- Shampoos
- Cosmetics
- Fabric detergents
What is the use of sulfonates?
Less hydrolysis than sulfates
What is use of
1. N-Acyl taurines
2. Monoalkyl phosphates
3. Acyl Isethionates
4. N-acyl sarcocinates
- Face and body liquid cleaners
- Low skin irritation
- Good foaming propeteries
What is incompatible with anionic?
Cationic
What is compatible with anionic?
Non-ionic and zwitterion surfactants
What is HLB?
A number that describes the hydrophilic-lipophilic nature of the surface active molecule
A measure of the proportion of hydrophilic vs lipophilic properties of a surfactant
Organizes info about surface active agents
What is the HLB for antifoaming?
1-3
What is the HLB for emulsifiers water in oil?
3-6
What is the HLB for wetting agents?
7-9
What is the HLB for emulsifiers oil in water?
8-18
What is the HLB for solubizers?
15-20
What is the HLB for detergents?
13-16
What happens a surface active agent has an HLB value less than 9?
Lipophilic
What are the characteristics that affect critical micill concentration?
- Surfactants migrating to interface
- CMC reached as surface is saturated
- Micelle formation
What are micelles?
Aggregates of surface active agents
What is the size range of micelles?
0.1 um with 50-100 molecules making up a single micelles
What is always equilibrium with monomers?
Micelles
How would CMC decrease?
Hydrophobic groups on surfactant increases
What has the higher CMC?
Ionic surfactants
What has a lightly lower CMC than ionics?
Zwitterionic
Why does electrolytes decrease CMC?
Electrolytes reduce repulsion between micells
Describe the effect of electrolytes on CMC?
More pronounced for anionic and cationic surface-active agents than for nonionics
What is molecular dispersion?
True solution solubized at the molecular level
What is colloidal dispersion?
Between Molecular and Coarse. Very small particle size dispersion. Colloids exhibit unique properties which differ by type.
What is lyophilic colloid?
In water, these are largely solvated and are often termed colloidal solutions.
What is lyophobic colloids?
In water, these are not solvated, thus they are a colloidal dispersion which is prone to aggregation like coarse dispersions.
What is association colloids?
more complex systems which we can manipulate to our needs.
What is coarse dispersions?
Larger particle sizes which behave as we have discussed
What occurs if a solid particle is placed in a liquid?
- Surface tension inherent to the particle
- SUrface tension inherent to the liquid
- Interfacial tension between the particle and liquid
What is the spreading coefficient?
How well liquid will spread over the solid particle
What is used to measure spreading coefficient?
Contact angle
How do you decrease surface tension?
Obtaining a positive spreading coefficient by decreasing the contact angle
What is spreading dependent on?
Forces of cohesion and adhesion
What is cohesion?
The creation of new surfaces that require work
What is adhesion?
The work required to separate 2 immiscible liquids
What is contact angle?
Measures the tendency of a liquid to wet a particular solid surface
What is the contact angle when completely wetted?
0
What is the contact angle when there is no wetting?
180
What is the contact angle when partially wetted?
0-180
What is the contact angle when highly wettable?
<20
What is the contact angle when not very wetted?
> 90
What are the 2 categories of rheology?
- Newtonian
- Nonnewtonian
What characterized Newtonian flow?
Constant viscosity regardless of shear rates applied
What is the difference between Newtonian and Nonnewtonian?
New: Rate of shear increases as shearing stress
Non: Shear rate and viscosity depends on flow characteristics
What are the types of non-newtonian flow
- Plastic
- Pseudoplastic
- Dilatant
Describe plastic flow
- Does not begin until shearing stress corresponding to certain yield value is exceeded
- The flow curve intersects the shearing stress axis and does not pass through the origin. The materials are elastic below the yield value
Describe Pseudoplastic flow
- Pseudoplastic substances begin flow when a shearing stress is applied, therefore, they exhibit no yield value
What is shear-thinning systems?
The increasing shearing stress will cause the rate of shear increases
Describe dilatant systems
Characterized by having a high percentage of solids in the formation
What is shear thickening systems?
Dilatant materials are those that increase in volume when sheared and the viscosity increases with increasing shear rate
What is thixotropic flow?
Viscosity decreases when flow is applied, but increases when flow is removed
What is antithixotropic flow?
Viscosity increases when flow is applied, bu decreases when flow is removed
How is thixotropy and anti-thixotropy similar?
Both are elastic systems or exhibit viscoelasticity
What is the purpose of making a stable, controllable suspension?
- An acceptable manufacturing process in terms of ease, affordability and stability of final product
- Delivery of API to desired site of action
- Optimum pharmacological effect at site of action
- Minimization of side effects
- Can’t stop aggregation only control it
What is the suspension theory?
Suspensions only need to be uniform at the time of delivery of dose
What is the key to formulating suspensions?
The ability to achieve uniformity through gentle shaking at the time we need to give a dose
How can suspension theory be accomplished affecting Stoke’s Law?
- Alter viscosity of medium by thickening
- Apply principles of rheology
- Alter sedimentation rate by suspending agent
- Using multiple methods not just one
How is innervation caused?
As internal concentration increases, so does the viscosity of the emulsion to a certain point, after which the viscosity decreases sharply
Changed from an o/w emulsion to a w/o or vice versa
Describe the difference between w/o and o/w emulsions when finely divided solids such as colloid clays is added?
O/w: Insoluble material is added to aqueous phase, aqueous volume is greater than oil volume
W/o: Insoluble material is added to oil phase, oil volume is greater than aqueous volume
How do prepare emulsions without innervation?
75% of the product must be in internal phase
Describe what a wetting agent is?
- Can be anionic, cationic, nonionic
- Both hydrophilic and lipophilic
- Lipophilic accounts for the surface activity of the molecule
What is the difference between anionic and cationic agents?
Anionic: lipophilic portion is - charged
Cationic: Positive charged
Neutralize each other and therefore incompatible
What is a nonionic emulsifier?
Show no inclination to ionize
Depending on nature, groups form o/w emulsions or w/o emulsions
What is caused by an unstable emulsion?
Flocculation
Creaming or sedimentation
Ostwald ripening
What are inhalation aerosols?
- MDIs
- Produce fine particles or droplets for inhalation through the mouth and deposition in the pulmonary tree
What are nasal aerosols?
- NAsal MDIs
- Produce fine particles or droplets for delivery through the nasal vestibule and deposition in the nasal cavity
What are lingual aerosols?
Produce fine particles or droplets for deposition on the surface of the tongue
What are topical aerosols?
Produce fine particles or droplets for application to the skin
What is the 2 phase aerosol system?
Liquid phase containing liquified propellant and product concentrate and the vapor phase
What is the 3 phase aerosol system?
- Layer of water immiscible liquid propellant
- Layer of highly aqueous product concentrate
- Vapor phase
What are the main parts of aerosols?
- Product concentrate (API)
- Propellant (liquified gas)
How is pressure of an aerosol controlled?
- Type and amount of propellant
- Nature and amount of product concnetrate
What is space sprays?
Contain a greater proportion of propellant than aerosols intended for surface coating therefore greater pressure
30-40psig, 21C, 85% propellant
What is the propellant content in surface aerosols?
30-70% propellant, 25-55psig, 21C
What is the propellant content of foam aerosols?
6-10% propellant, 35-55psig, 21C
Why is particle size important for inhalation
- 2 um will reach respiratory bronchioles
- <2µm will reach alveoli and alveolar ducts
What is the difference between central and peripheral lung delivery?
Central: Particle will diffuse through the mucus layer (mucocillary clearance)
Peripheral: Particle is broken down by macrophage (macrophage clearance)
What is the USP requirements for containers?
- Well closed container
- Tight container
- Hermetic container (air tight): may be sterile or multidose
What are the types of glass packaging?
- Highly resistant borosilicate glass (most resistant)
- Treated soda lime glass
- Soda lime glass
- NP: general purpose soda lime glass
What is glass packaging tested for?
Resistance to water attacks
What is any component that is intended to furnish pharmacologic activity or have direct effects when used?
API
What is a specific quantity of a drug of uniform specified quality produced according to a single manufacturing order during the same cycle of manufacturing?
BAtch
What is the use of validated in-process sampling and testing methods where results prove that the process has done what it purports to do for the specific batch concerned?
Batchwise control
What is a documented testimony of qualified authority?
Certification
What is the determination through inspection of the extent to which a manufacturer is acting accordance with prescribed regulations, standards, and practices?
Compliance
What is any ingredient used in the manufacture of a drug product?
Component
What is a finished form that contains an active drug and inactive ingredient?
Drug product
What is any component other than the active ingredients in a drug product?
Inactive ingredient
What is a batch or any portion of a batch having uniform specified quality and a distinctive identifying lot number?
Lot
What is any distinctive combination of letters, numbers, or symbols identifying a drug?
Lot number, controls number, or batch number
What is a record containing the formulation, specifications, manufacturing procedures, quality assurance requirements, and labeling of a finished product?
Master Record
What is provision to all concerned the evidence needed to establish confidence that the activities relating to quality are being performed adequately?
Quality assurance
What is a documented activity performed in accordance with established procedures on a planned and periodic basis to verify compliance with the procedures to ensure quality?
Quality audit
What is the regulatory process through which industry measures actual quality performance compares it with standards and acts on the difference?
Quality control
What is the organizational element designated by a firm to be responsible for the duties relating to quality control?
Quality control unit
What is an area that is marked, designated, or set aside for the holding of incoming components prior to acceptance testing and qualification for use?
Quarantine
What is a sample that accurately portrays the whole?
Representative sample
What is the activity where by the finished product or any of its components is recycled through all or part of the manufacturing process?
Reprocessing
What is the concentration of the drug substance per unit dose or volume?
Strength
What is signed by a second individual or recorded by automated equipment?
Verified
What is documented evidence that a system does what it purports to do?
Validation
What is documented evidence that a process does what it purports to do?
Process validation
What is a prospective experimental plan to produce documented evidence that the system has been validated?
Validation protocol
What are the applications of cGMP?
- Applies to manufacturing of API and Pharmaceutical excipients separately from the finished pharmaceutical product
- Applies to clinical trial materials
- Applies to biologics
- Applies to medical devices
What is the cGMP for community or institutional pharmacies?
Engaging in manufacture, repackaging, or relating of drugs and drug products and beyond the usual conduct of professional dispensing
What do community pharmacies register as for cGMP?
FDA, 503b compounder, manufacturer, distributor
Subject to FDA inspection at regular intervals
What is the difference between pharmaceutical manufacturing and compounding preparation?
P: large scal production
C: prescriptions for specific patients
What the compliances of cGCP for compounders?
- Training
- Quality of ingredients
- OSHA and MSDS are available for all ingredients and chemicals
- Quality control
- Environment of compounding area
- Records
- SOPs
- Controlled Acess
What are the USP criteria for compounding products?
- Does, safety and intended use
- Master formulation record and compounding record
- Quality of ingredients
- Clean and sanitized area
- One preparation compounded at a time
- Appropriate and functioning equipment
- Beyond use date
- Appropriate clothing and hygiene
- Critical processes verified
- Method of assessment is defined and performed for final prep
- Patient consultation occurs
What are the categories of compounds?
- Simple (gel and oral)
- Moderate (requires special calculations or procedures: suppository, unit mold, cream)
- Complex (specialized equipment and procedures: modified release dosage forms)
What are the issues with plastic containers?
- Leaching
- Sorption
- Deformation
What is leaching?
Movement of components of a container into the content
What is sorption?
Binding of molecules to polymer materials including both adsorption and absorption
What is deformation?
External factors such a temperature and physical stress