Pharmaceutical Particle Size Measurement Quiz

False (B)

emulsion stability

<p>sedimentation</p> Signup and view all the answers

<p>Milling = Reduces particle size Homogenization = Reduces droplet size in emulsions Particle size measurement = Determines size distribution Sedimentation = Determines particle settling rate</p> Signup and view all the answers

<p>It gives an indication of the emulsion droplet size on storage. (C)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>The percentage of particles above or below a given size (B)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>They are the same.</p> Signup and view all the answers

<p>size</p> Signup and view all the answers

<p>2000 µm = 20000.1 1000 µm = 10006.6 500 µm = 49.5 180 µm = 79.2</p> Signup and view all the answers

<p>By number, surface, mass, or volume (B)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>lognormal</p> Signup and view all the answers

<p>particle size</p> Signup and view all the answers

<p>Measures relatively few particles (C)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>ImageJ</p> Signup and view all the answers

<p>range</p> Signup and view all the answers

<p>Image Analysis = Counts pixels in each region, constructs a histogram Light Scattering = Analyzes the diffraction pattern to infer particle size SEM = Measures particles in the range of 10 µm TEM = Technique to measure very small particles</p> Signup and view all the answers

<p>The connection between particle size and settling rate. (A)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>rw²</p> Signup and view all the answers

<p>viscosity</p> Signup and view all the answers

<p>Sedimentation velocity (v) = Rate at which suspended particles settle r1 = Density of the fluid r2 = Density of the particle η = Fluid viscosity</p> Signup and view all the answers

<p>Directly measuring the settling velocity (A)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>material settled</p> Signup and view all the answers

<p>samples</p> Signup and view all the answers

<p>Microscopy and image analysis (D)</p> Signup and view all the answers

<p>To separate and analyze particles based on their size (C)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>50 μm</p> Signup and view all the answers

<p>diameter</p> Signup and view all the answers

<p>Mesh size = Determines the particle size it will allow to pass through. Sieve nest = A stack of sieves of decreasing mesh size. Pan = The bottom tray that collects the smallest particles Sieve equivalent diameter = The size of a sphere that will pass the square hole</p> Signup and view all the answers

<p>The particles are larger than the sieve apertures. (A)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>Sieve holes may be damaged or vary in size</p> Signup and view all the answers

<p>stick</p> Signup and view all the answers

<p>By weighing the particles in each sieve (C)</p> Signup and view all the answers

The size of individual particles within a material, typically measured in micrometers (µm).

Particle size is crucial because it impacts the physical properties of medicine ingredients, influencing things like how easily a powder flows or how a tablet forms.

Particle size analysis helps confirm that a manufacturing process has been successful, such as milling a solid or homogenizing an emulsion. It ensures consistent quality.

Particle size analysis can provide clues about the stability of a product over time. For instance, changes in emulsion droplet size during storage may indicate product degradation.

A technique used to measure the size distribution of particles in a sample. It relies on the observation that larger particles settle faster than smaller particles in a fluid.

Particle size affects the rate at which a medicine dissolves and is absorbed into the body. Smaller particles tend to dissolve and absorb faster.

Different techniques are used to measure particle size, each with its specific principles and limitations. Common methods include microscopy, laser diffraction, and dynamic light scattering.

It represents the percentage of particles above or below a specific size, rather than the percentage at that specific size.

It's a visual representation of the distribution of particle sizes, where the x-axis represents size and the y-axis represents the percentage of particles.

The distribution of particles can be considered by different aspects: Number, Surface, Mass, or Volume.

In the case where the density of particles is consistent regardless of size, the mass distribution mirrors the volume distribution.

A sieve analysis is a technique that involves passing a sample of particles through a set of sieves with decreasing aperture sizes. This helps determine the size distribution of the particles based on the amount of material retained in each sieve.

The nominal aperture size refers to the theoretical size of the openings in a sieve, which is often expressed in microns (µm).

A sieve stack is a series of sieves arranged according to decreasing aperture sizes, creating a layered structure for separating particles based on their size.

Lognormal Distribution is a probability distribution where the logarithm of a variable is normally distributed. It is often used to model particle size distributions.

A lognormal distribution occurs when the particle size data is plotted on a logarithmic scale, resulting in a bell-shaped curve. This indicates that the size distribution is not evenly spread.

A technique that uses a computer to analyze images and count pixels within defined regions to determine particle size distribution. This method is suitable for measuring the size and shape of relatively small particles.

The phenomenon where light waves bend and spread as they encounter particles. This scattering pattern is unique to the size and shape of the particles, providing information about their dimensions.

A common method for determining particle size distribution, often using lasers or a light source to illuminate the sample and measure the scattering patterns.

The unique pattern created when light interacts with particles. This pattern, which depends on the particle size and shape, can be used to estimate particle size.

Calculating particle size distribution from a measured diffraction pattern is very challenging because there is no simple direct relationship between the two. Specialized software and algorithms are required to interpret the scattering pattern.

The speed at which particles settle in a fluid.

The rate at which suspended particles settle is directly related to their size.

A formula that describes the relationship between particle size, fluid properties, and sedimentation velocity.

A method of measuring particle sizes by measuring the amount of material settled in a specific time. Measures material settled on an immersed pan.

A method of measuring particle sizes by measuring the amount of material remaining in suspension over time.

A technique that speeds up sedimentation by using centrifugal force.

A device that measures particle sizes by removing samples from the suspension at different times and analyzing the particle content.

A device that measures particle sizes using centrifugal sedimentation and light scattering.

A group of advanced technologies used for measuring particle sizes and shapes.

The analysis of images captured by microscopes to measure and characterize particles.

This technique separates particles by size using woven or perforated surfaces, allowing smaller particles to pass through while larger ones are retained.

A common type of sieve that has square openings in its mesh. The size of these openings determines which particles can pass through.

The size of the sphere that would pass through the square opening of a sieve. It is used to characterize particle size.

A set of sieves with decreasing mesh sizes stacked on top of each other, with a pan at the bottom to collect the smallest particles.

The process of shaking a sieve nest to allow particles to pass through different sized meshes, separating them based on their size.

Inequalities in the size of the sieve openings caused by manufacturing defects or damage.

Tiny particles of the sample that can cling to the sieve wires, effectively reducing the size of the sieve openings.

When particles in the sample stick together due to forces like static electricity or surface tension, preventing them from passing through the sieve.

The possibility that the shaking process can break down larger particles, creating artificially small particles that affect the results.

A problem that occurs when the sieve is not shaken sufficiently, resulting in particles not reaching their appropriate size category.