Calibration of Dissolution
Apparatus
Presented by: Submitted to:
Himanshu Shahu Dr. Gaurav Jain
M.Pharm(1st sem) Dept. of Pharmaceutics
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WHAT IS CALIBRATION ?
The activity of checking, by comparison with a standard,
the accuracy of a measuring instrument of any type. It
may also include adjustment of the instrument to bring it
into alignment with the standard.
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WHAT IS DISSOLUTION?
The process by which a solid solute enters in to a solution
i.e. mass transfer from solid surface to liquid phase
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WHY DISSOLUTION STUDY?
Estimation of amount of drug released per unit time.
Batch to batch quality control.
For product development.
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COMMONLY USED DISSOLUTION MEDIUM:
Purified water
Dilute acid (0.001N-0.1N HCL)
Stimulated gastric fluid (pH 1.2)
Stimulated intestinal fluid (pH 6.8)
Surfactants (e.g. Polysorbate, SLS)
Aqueous buffers (pH 5-7)
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Calibration of Dissolution Tester :
Physical Parameters:
1)Shaft Rotating
2)Speed Wobble
3)Temperature
4)Shaft Alignment
5)Instrument Level
6)Vibration
7)Shaft Centering
USP Tablet Calibrators
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Dissolution Tablet Calibrators:
Prednisone Tablets
(Disintegrating)
Salicylic Acid Tablets
(Non-disintegrating)
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Item Prednisone Tablets Salicylic acid Tablets
Type Disintegrating Non-disintegrating
Amount 10mg/tab 300mg/tab
Apparatus I and II I and II
RPM 50 100
Dissolution Medium Deaerated Water, 500 ml Deaerated0.05 M
Phosphate Buffer
pH7.4±0.05, 900 ml
Time point 30 minutes 30 minutes 31
Item Prednisone Tablets Salicylic acid Tablets
Max. λ(nm) 242 296
Packaging Plastic bottle Blister pack
% alcohol in Std. solution ≤5 % ≤1 %
Acceptance values (%la.)
Apparatus I 51-81 23-30
Apparatus II 26-47 17-25
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Tablet Calibration:
Study the Certificate of Analysis (COA) of the USP tablet calibrators
Prepare deaerated dissolution medium
Setup the dissolution tester
Pour the dissolution medium into the vessels and equilibrate to 37 °C, use
immediately (Check and record the temperature of each vessels)
Weigh each tablet calibrators
Insert the tablet calibrators into the baskets/ Drop the tablet calibrators
into the vessels
Activate the spindles at the desired speed
Withdraw the specimens at the stated time and immediately filter
Recheck and record the temperature of the vessels
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Measure the absorbance of samples and standard solutions
“There are many reasons that a tablet
calibration test may fail. The items in the
checklist may or may not the reason for a failed
test. Deaeration and vibration are two of the
largest contributors to failure.”
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Influence of Release Gases:
The bubbles that appear in media as the equilibrium is disturbed may:
– buoyancy dissolution rate
– available surface area dissolution rate
– associate with aggregate particles random concentrations of the particles in the
solvent stream
-collect at the screen on the basket changing the effective porosity of the mesh
-cling the particle to the apparatus and vessel walls
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-influence on pH of the media
Deaeration Methods:
Helium flushing
Sonicating + Vacuum
Automated media degasser (ex. DosaPrep®)
Warming to 41 °C + filtering + Vacuum
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Maintenance:
Careful cleaning is required to ensure there is no contamination
between tests.
Handling the basket and shaft/ paddles with care Visually inspect
the bath water weekly for algae or other foreign material.
Water in the bath is reasonable clean to ensure that the
circulating pump is also clean.
Do not allow dissolution media sit on the system.
Clean up dissolution media whenever it is spilled on the system
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Maintenance Schedule:
Frequency Procedure
After each test Clean up system
Weekly Inspect circulating water pump; bath
water
Monthly Replace bath water
Every 6 months -Check temperature calibration
-Calibration of the system
-Inspect guide rods and spindle bearings
Annually Inspect belts; Idler pulleys
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Every 2 years Replace belts