Lecture 4 Flashcards
Ways to measure particle size
Microscopy, sieving or screening.
Why is weighing crucial in drug formulation?
Weighing ensures accurate dosage and product quality.
What factors affect mixing in drug formulation?
Mixer design, static charges, and the three mechanisms of mixing.
Topical administration use and benefits.
Topical administration is used for local effects on the skin or mucous membranes. It can avoid first-pass metabolism and provide sustained drug delivery
List the 4 types of mixers mentioned in drug formulation.
Fixed shell mixers, rotating shell mixers, solid-liquid mixers, and liquid-liquid mixers.
What factors influence the milling process?
Moisture content, heat, product specifications, capacity, versatility, and safety features.
What are the techniques used in milling
Temperature control, pre-treatment, subsequent treatment, and dual processes.
What factors influence the drying rate?
Air temperature, humidity, and drying duration.
Provide examples of excipients used in drug formulation.
Fillers, binders, anti-adherents, lubricants, glidants, disintegrants, coatings, colors, sorbents, preservatives, flavors, and sweeteners.
Give examples of excipients and their functions in tablet formulation.
Binders (for cohesion), disintegrants (for breakdown), lubricants (to prevent sticking), and colourants (for appearance).
What factors affect the flow properties of a powder blend in tablet manufacturing?
Particle size, shape, surface texture, density, moisture content, vibration, and aeration.
How do cohesive forces like van der Waals forces influence powder flowability?
They can hinder the flow of powders by causing particles to stick together.
What techniques can improve powder flowability?
Altering particle size distribution, using spherical particles, spray drying, and adding excipients like glidants to reduce moisture and static charges.
What is granulation, and why is it important in tablet manufacturing?
Granulation is the process of forming granules to improve flowability, compressibility, and uniformity of the powder blend.
What are the two primary methods of granulation
Dry granulation and wet granulation.
What is dry granulation, and when is it used?
Dry granulation uses mechanical force to create granules, suitable for APIs sensitive to moisture or heat.
What is wet granulation, and how does it work?
Wet granulation uses a liquid binder to bind particles, followed by drying and milling.
What types of tablet presses are used in manufacturing?
Single station presses and multi-station rotary presses.
Why are tablets coated?
To mask taste or odor, extend shelf life, and control the release of the API.
What is the purpose of enteric coatings?
To protect acid-sensitive drugs, allowing them to dissolve in the intestine rather than the stomach.
What are the different types of coated tablets?
Sugar-coated, film-coated, enteric-coated, and controlled-release tablets.
What are some common tablet defects, and how are they addressed?
Defects can include cracking, chipping, and sticking, which are addressed by optimising formulation and manufacturing processes.
Compression
reduction of volume of the powder
2 methods used for dry granulation.
Slugging and rolling
Slugging
API mixed with excipients are compressed to form a large tablet. Then milled and screened to produce granules.
Rolling
Powder is formed into a cake by squeezing between the rolls. Then milled and screened to produce granules.
Binders examples
lactose, cellulose, corn/maize starch
Disintegrants examples
Crospovidone
Antioxidants examples
Ascorbic acid, EDTA
Preservative examples
Benzoic acid, methyl, propyl, benzyl
Buffering agent example
Sodium citrate
Lubricant examples
Calcium stearate, veg oil
Colourants examples
Titanium Oxide, Carotene
Benefits to coating tablets.
Improve unpleasant taste, smoother finish is easier to swollow, extend shelf life.
Enteric coating
Resistant to acidic pH
2 types of coating machines
coating pans and automatic coaters
What are controlled release tablets?
Allow slow release of API
