The post Micromeretics and Powder Rheology: Methods of determining particle size and volume – Optical microscopy, Sieving and MCQs for GPAT, NIPER, Pharmacist and Drug Inspector exam appeared first on Gpatindia: Pharmacy Jobs, Admissions, Scholarships, Conference,Grants, Exam Alerts.
]]>Equivalent diameter: It is used to determine projected area diameter, Feret’s diameter and Martin’s diameter.
Range of analysis: 1 μm to about 100 μm.
Methodology:
Table 1 – Representation of number distribution values obtained by the microscopic method
Ocular
divisions |
Particle size
range (µm) |
Mean particle
size (µm) |
Frequency (no. of
particles in each diameter) |
Frequency
(%) |
Cumulative
frequency (%) |
Log
particle size |
0–1 | 0–20 | 10 | As counted | – | – | 1.00 |
1–2 | 20–40 | 30 | As counted | – | – | 1.47 |
Advantage:
Disadvantages:
Sieving Technique:
Equivalent diameter: Sieve diameter—the particle dimension that passes through a square aperture.
Range of analysis: 5 μm to about 1000 μm.
Methodology:
Machines:
Fig 1 – Arrangements of sieves during sieving and sizes of standard sieves (taken from size separation slideshare.net)
Table 2 – Sieve no. with aperture size
US sieve no. | Aperture size |
10 | 2.00mm |
14 | 1.40mm |
18 | 1.00mm |
20 | 840 µm |
25 | 710 µm |
40 | 420 µm |
60 | 258 µm |
80 | 180 µm |
100 | 149 µm |
120 | 125 µm |
200 | 74 µm |
400 | 37 µm |
Table 3 – Representation of weight distribution values obtained by the sieving method
Sieve numbers
(passed/retained) |
Size range
(µm) |
Mean size
(µm) |
Weight retained
(g) |
Weight
retained (%) |
Cumulative weight
retained (%) |
Log particle
size |
25/40 | 710–420 | 565 | As weighed | – | – | 2.75 |
40/60 | 420–258 | 339 | As weighed | – | – | 2.53 |
Advantages:
Disadvantages:
Multiple choice question (MCQs)
1.Andreason apparatus consist of
a)Reference electrode
b)Pipette
c)Glass electrode
d)Hydrogen electrode
2.For a sphere value of αs / αv equals to
a)6
b)9
c)8
d)18
3.The physical, chemical, and pharmacological properties of a drug are directly affected by
a)Size
b)Surface area
c)Both of the above
d)None of the above
4.____ is the science and technology of small particles
a)Micromeretics
b)Microscopy
c)Rheology
d)None of the above
5.The unit of particle size used is in
a)Kilometer(km)
b)Centimeter(cm)
c)Millimeter(mm)
d)Micrometer(µm)
6.1 micrometer(µm) is equal to
a)10-5m
b)10-6m
c)10-7m
d)10-8m
7.Particle size with diameter of 0.5 to 1.0 micrometers(µm) is useful for
a)Emulsions
b)Suspensions
c)Both of the above
d)None of the above
8.The size of a sphere is freely stated in terms of its
a)Area
b)Diameter
c)Radius
d)Volume
9.Which property affect physical, chemical and biological property of drug?
a)Density
b)Surface area
c)Particle size
d)All of the above
10.Particle size can be reduced by,
a)Mortar and pestle
b)Sieve
c)Grinder
d)Both a and c
11.Sedimentation rate can be decreased by …………. Particle size,
a)Increase
b)Decrease
c)Unchanged
d)None of the above
12.Which is smallest?
a)Micrometer
b)Millimeter
c)Nanometer
d)Catharometer
13.Micromeretics is a study of
a)Particle size
b)Particle shape
c)Particle distribution
d)All of the above
14.Particle size is determined by
a)Sieving method
b)Sedimentation method
c)Microscopy
d)All of the above
15.Sedimentation of suspension is determined by
a)Stokes law
b)Car’s index
c)Hausner ratio
d)None of the above
Solutions:
References:
1. GAURAV KUMAR JAIN – THEORY & PRACTICE OF PHYSICAL PHARMACY, 1st edition 2012 Elsevier, page no. 31-34.
2. Martins Physical Pharmacy, 6th edition 2011, page no. 817-819.
List of Successful GPATINDIAN CANDIDATES
Participate in Online FREE GPAT TEST: CLICK HERE
Participate in Online FREE Pharmacist TEST: CLICK HERE
Participate in Online FREE Drug Inspector TEST: CLICK HERE
Participate in CSIR NET JRF Mock Test
The post Micromeretics and Powder Rheology: Methods of determining particle size and volume – Optical microscopy, Sieving and MCQs for GPAT, NIPER, Pharmacist and Drug Inspector exam appeared first on Gpatindia: Pharmacy Jobs, Admissions, Scholarships, Conference,Grants, Exam Alerts.
]]>