Industrial Pharmacy Lab2 : Rheology Part I

Frictional (electrostatic) forces = Forces generated on the surface of particles due to friction between them Particle shape = Spherical particles with smooth surface have good flowability, while irregular shape particles hinder flow Particle size = Large particles with rough surfaces can lead to blockage of machine orifice Moisture = High moisture content can lead to formation of sticky particles and bad flowability

Frictional (electrostatic) forces = Generated on particle surfaces due to friction, affects flowability Particle shape = Irregular shape particles fill spaces and hinder flow Particle size = Large particles mostly have rough surfaces, causing issues in flow Moisture = Acts as binder between particles but high content results in sticky particles and bad flowability

Spherical particles with smooth surface = Good and free flowability Irregular shape particles with flat or rough surfaces = Bad flowability due to hindering the flow Large particle size = Rough surfaces may cause blockage of machine orifice High moisture content = Results in formation of sticky particles and bad flowability

<p>Forces generated on particle surfaces due to friction = Frictional (electrostatic) forces Irregular shape particles filling spaces and hindering flow = Particle shape Large particles mostly having rough surfaces causing blockage = Particle size Acting as a binder but high content leads to sticky particles = Moisture</p> Signup and view all the answers

<p>Rheology = The study of flow properties of materials Powder flowability = Determines how well powder flows Freely flowable powder = Powder that flows easily without sticking Intermolecular forces = Weak forces on the surface of particles</p> Signup and view all the answers

<p>The need for proper understanding of rheological properties of pharmaceutical materials is essential during preparation, development and evaluation of pharmaceutical dosage form. = Ensuring quality and consistency in dosage form production Tablets and capsules are most commonly used dosage forms; an important consideration in manufacturing these dosage forms is the flow of solid powder particles from the hopper through feeder. = Importance of consistent flow rate for uniformity in final products Preparation of such dosage forms required measured filling for the production of each unit; and the uniformity of the final products requires constant flow rate of particles. = Achieving constant weight and content uniformity in tablets/capsules Factors reducing flow rate: surface of particles (different charges), like Van der Waals forces. = Influences on powder flowability</p> Signup and view all the answers

<p>The die must be filled with the same amount of granules in each compression time; in order to get such amount, constant flow rate of particles should be ensured by having freely flowable powder or granules. = Consistent compression leading to uniform tablet weight A good flow will lead to constant weight of powder reach die at each compression; as a result, no weight variation, constant content uniformity and good bioavailability. = Impact of powder flow on product quality</p> Signup and view all the answers

<p>Glidant = Prevents friction between particles Lubricant = Decreases friction between particles and machine walls Granulation = Solves problems from irregular particle size or shape Drying = Removes excess moisture but must be carefully timed</p> Signup and view all the answers

<p>Smoothing particle surfaces = Improves powder flowability Reducing electrostatic charge = Enhances powder flowability Moisture reduction on particles = Aids in powder flowability Alteration of particle shape and texture = Produces free flowing granules</p> Signup and view all the answers

<p>Granulation = Converts fine powder into uniform size granules Over-drying = Reverts granules back to fine powder Spray drying = Produces spherical free flowing granules Drying time control = Critical in maintaining granule form</p> Signup and view all the answers

<p>Hydrophobic nature of additives = Can cause stickiness in large concentration Proper lubricant concentration = Critical for avoiding stickiness and bad flowability Proper glidant concentration = Critical for maintaining good flowability Over-drying during drying process = Can lead to stickiness in the final product</p> Signup and view all the answers

<p>Glidant = Acts to improve powder flow through various mechanisms Particle shape alteration by spray drying = Produces granules with better flow properties Granulation of fine powder = Results in uniform size and shape granules for improved flow Moisture reduction on particle surfaces = Reduces clumping and aids in smooth flow</p> Signup and view all the answers

<p>Glidant effect on electrostatic charge adhesion = Reduces cohesion between particles Lubricant reducing friction between particles and machine walls = Decreases cohesion for better flow Granulation producing uniform size granules = Minimizes cohesion between irregular particles Proper drying to remove excess moisture = Helps prevent particle agglomeration and cohesion</p> Signup and view all the answers