Test
DF08 Powder processing that influences product performance
Este test tiene tipos de pregunta que se abren en el reproductor de siempre.
Preguntas del test (17)
1Size reduction is important to [blank_start]increase[blank_end] surface area, that leads to [blank_start]increased[blank_end] dissolution rate & bioavailability. It is also important improve [blank_start]flow properties[blank_end] of powders that are needle shaped or irregular in shape and tend to form [blank_start]bridging[blank_end] (arching). It can also improve tablet-tablet [blank_start]content uniformity[blank_end] as there will be more particles per unit weight.
- Aincrease
- Bincreased
- Cflow properties
- Dbridging
- Econtent uniformity
2Trituration is size reduction using a mortar and pestle in the pharmacy.
- AVerdadero
- BFalso
3Order these methods of size reduction in increasing fineness of particles. (4 - most fine.)
[blank_start]2[blank_end]. Compression.
[blank_start]1[blank_end]. Cutting
[blank_start]3[blank_end]. Impact
[blank_start]4[blank_end]. Attrition (friction and pressure)- A2
- B1
- C3
- D4
4Problems (during or following dry milling) include formation of [blank_start]amorphous[blank_end] drug, which is not always desired, change to another [blank_start]polymorphic[blank_end] form, [blank_start]heat[blank_end] production, and so [blank_start]degradation[blank_end] due to heat build-up. Hygroscopic substances absorb [blank_start]moisture[blank_end] so this is something to take into account. Also [blank_start]static[blank_end] build-up, and [blank_start]plastic[blank_end] deformation may occur, rather than cracking.
- Aamorphous
- Bpolymorphic
- Cheat
- Ddegradation
- Emoisture
- Fstatic
- Gplastic
5Problems (during or following wet milling) & solutions may include production of [blank_start]nano-sized crystals[blank_end] and [blank_start]Ostwald[blank_end] ripening. Production of nano crystals depends on mill or homogeniser but crystal growth is [blank_start]likely[blank_end] once milling stops. Ostwald ripening is the phenomenon whereby smaller particles with [blank_start]higher[blank_end] surface energy give up [blank_start]mass[blank_end] to large particles with [blank_start]lower[blank_end] and more stable surface energy, so that small particles get [blank_start]smaller[blank_end] and large particles get [blank_start]larger[blank_end].
- Anano-sized crystals
- BOstwald
- Clikely
- Dunlikely
- Ehigher
- Fmass
- Glower
- Hsmaller
- Ilarger
6Size increase is important because several components can be combined to form granules or pellets, thus reducing risk of [blank_start]segregation[blank_end] of the individual components; [blank_start]improving[blank_end] flow properties for processing (filling tablet die or capsule). Also, uniformly sized wet granules can promote [blank_start]uniform drying[blank_end]. Controlled particle size can give [blank_start]better[blank_end] mixing & [blank_start]reduced[blank_end] segregation; particularly important for tablet die or capsule filling.
- Asegregation
- Bimproving
- Cuniform drying
- Dbetter
- Ereduced
7Size increase can be achieved by:
1. Spray [blank_start]Drying[blank_end] (bottom-up)
2. [blank_start]Precipitation[blank_end] (bottom-up)
- to make nano-sized particles (amorphous or crystalline)
3. [blank_start]Granulation[blank_end] & pelletisation (more later)
- components are mixed together, granulator may be used- ADrying
- BPrecipitation
- CGranulation
8[blank_start]Drying[blank_end] is the vaporisation and removal of water and other liquids from a sample to form a “dry solid”
[blank_start]Moisture content[blank_end] is the mass of moisture present in a sample. It is the loss in weight (%) after oven drying at 102°C until constant weight is obtained” %Moisture content = (Initial weight – dry weight)*100 /Initial weight
[blank_start]Relative humidity (RH)[blank_end] is the saturation level of the air with water vapour-normally expressed as a percentage. A higher percentage means that the air–water mixture is more humid. At 100% RH, the air is saturated. RH depends on moisture content and temperature.- ADrying
- BMoisture content
- CRelative humidity (RH)
9Pharmaceutical situations where drying of powders/solid occurs:
• to dry drug & excipients to [blank_start]reduce[blank_end] moisture content; thus [blank_start]increase[blank_end] stability; improve properties before [blank_start]milling or mixing[blank_end]
• to dry granules after a wet granulation process to [blank_start]improve handling, filling/flow/packaging[blank_end] (e.g. granulation)
• to prepare “vaccines” & other products which are marketed as [blank_start]moisture-free[blank_end] & able to be [blank_start]reconstituted[blank_end] before use (often freeze-drying)
• to prepare drug (or drug-excipient mix) in desired [blank_start]solid state/particle size distribution[blank_end] (often spray drying)- Areduce
- Bincrease
- Cmilling or mixing
- Dimprove handling, filling/flow/packaging
- Emoisture-free
- Freconstituted
- Gsolid state/particle size distribution
10Drying methods:
1. [blank_start]Convection[blank_end]
• air flows past solid &/or solid moves within the equipment (includes spray drying)
2. [blank_start]Conduction[blank_end]
• equipment is heated
• vapour may be removed by operation under vacuum or by air convection process
3. [blank_start]Radiation[blank_end]
• solids (plus moisture) are heated by infra-red radiation
• moisture within solids is heated by microwave- AConvection
- BConduction
- CRadiation
11Static-bed driers:
- Advantages: [blank_start]easy[blank_end] to clean, [blank_start]low[blank_end] cost, ease of [blank_start]mechanical[blank_end] operation
- Disadvantages: [blank_start]slow[blank_end] drying, heat gives [blank_start]decomposition[blank_end], [blank_start]non-uniform[blank_end] temperature
Fluidized bed driers:
- Advantages: [blank_start]rapid[blank_end] drying, [blank_start]uniform[blank_end] bed temperature, lower handling [blank_start]costs[blank_end], coprocessing
- Disadvantages: [blank_start]heated[blank_end] air gives decomposition, agitation gives particle size [blank_start]reduction[blank_end], material retention and care in [blank_start]cleaning[blank_end]- Aeasy
- Blow
- Cmechanical
- Dslow
- Edecomposition
- Fnon-uniform
- Grapid
- Huniform
- Icosts
- Jheated
- Kreduction
- Lcleaning
12Freeze drying avoids:
- AThe liquid-gas transition
- BThe solid-gas transition
- CThe liquid-solid transition
133 phases of freeze drying/lyophilisation:
1. The first phase is [blank_start]freezing[blank_end].
2. Second phase is the [blank_start]primary drying[blank_end]: The chamber pressure is [blank_start]reduced[blank_end], and heat is applied to the product to cause the frozen mobile water to [blank_start]sublime[blank_end].
3. Third phase is [blank_start]secondary drying[blank_end]: The temperature is [blank_start]increased[blank_end] to desorb bound water such as water of crystallization.- Afreezing
- Bprimary drying
- Csecondary drying
- Dreduced
- Esublime
- Fincreased
14Select all the advantages of freeze drying.
- Alow temperatures so little degradation
- Bproduct is light and porous (ready solubility)
- Cno concentration of solution during drying
- Dno contact with air
- Ehygroscopic product
- Fprocess slow
- Gequipment expensive
- Hlimited to certain products
15Methods of mixing include diffusive, convective, and shear.
Diffusive mixing is where [blank_start]individual[blank_end] particles move to change position relative to neighbouring particles in a [blank_start]random[blank_end] way. An expanded bed allows particles to move. [blank_start]Free[blank_end]-flowing powders undergo diffusive mixing readily, and density & particle size [blank_start]differences[blank_end] promote diffusive mixing.
Convective mixing is [blank_start]transfer[blank_end] groups between adjacent locations. A portion of the mix is removed from one place & deposited in another; achieved by [blank_start]spatula, blades, or revolving screw[blank_end] (helix).
Shear mixing is where particles are [blank_start]forced[blank_end] to move past each other; slip [blank_start]planes[blank_end] are created by the mixing procedure. [blank_start]Large[blank_end] agglomerates are usually broken up by shear-mixing; [blank_start]small[blank_end] aggregates are often not broken up (cohesive forces determine if particles can be separated by this process). A more intense blending is required to break [blank_start]small aggregates[blank_end]. Energy is supplied to disrupt, and shear planes are within the mass.- Aspatula, blades, or revolving screw
- Btransfer
- CFree
- Dindividual
- Erandom
- Fdifferences
- Gforced
- Hplanes
- ILarge
- Jsmall
- Ksmall aggregates
16Achieving a good random mix can be extremely difficult in ome situations. For example, when the drug [blank_start]content[blank_end] is only a small proportion of the mix, when drug particles (or other ingredients) are [blank_start]aggregatedor agglomerated[blank_end] initially, when the mixing procedure tends to "[blank_start]compact[blank_end]" particles rather than separate them, when [blank_start]non-uniform non-spherical[blank_end] particle shape interferes with particles moving past each other easily, and when the average particle size & [blank_start]distribution[blank_end] of the different components are very [blank_start]different[blank_end] & demixing (segregation) tends to occur.
- Acontent
- Baggregatedor agglomerated
- Ccompact
- Dnon-uniform non-spherical
- Edistribution
- Fdifferent
17Demixing (segregation) can occur at the [blank_start]same time[blank_end] as mixing occurs. Segregation may occur when one component [blank_start]concentrates[blank_end] at one position in the mixer, especially where [blank_start]symmetric[blank_end] repetitive movement occurs. It can occur when the [blank_start]external[blank_end] mixing procedure [blank_start]stops[blank_end].
Factors promoting segregation are [blank_start]differences[blank_end] in particle size, shape and density—so [blank_start]gravity[blank_end] can lead to segregation. [blank_start]Asymmetric[blank_end] movement or [blank_start]abrupt reversal[blank_end] in movement helps to reduce this.- Asame time
- Bconcentrates
- Csymmetric
- Dstops
- Eexternal
- Fdifferences
- Ggravity
- HAsymmetric
- Iabrupt reversal
Información
- Descripción
- (Formulation) PHCY211 Test sobre DF08 Powder processing that influences product performance, creado por Mer Scott el 28/04/2018.
- Autor
- Mer Scott
- Idioma
- English
- Visitas
- 6
- Etiquetas
- Valoración
- Aún sin valoraciones Valora este test