This document discusses dissolution testing, which is an important quality control procedure for pharmaceutical dosage forms. It begins by introducing dissolution testing and explaining that it measures the rate and extent of dissolution of a drug product under specified conditions. It then describes the various apparatus used for dissolution testing according to official compendia like the USP, including the basket, paddle, reciprocating cylinder, flow-through cell, paddle-over-disk, rotating cylinder, and reciprocating disk methods. The document also discusses factors that can influence dissolution and concludes that dissolution testing is a valuable tool for evaluating batch-to-batch consistency and biological availability of drugs from formulations.

1. Presented by
Mr. MAYUR R. KHINVASARA
(M. Pharm. Sem. I)
Roll No. A-11
Guided by
Dr. SANJAY B. PATIL
( M. Pharm., Ph.D.)
Department of Pharmaceutics
S. S. D. J. COLLEGEOF PHARMACY,CHANDWAD
DISSOLUTION TESTING :
A HEART OF PHARMACEUTICS

2. CONTENTS
 Introduction
 Dissolution
 Dissolution testing
 Need of dissolution
 USP dissolution apparatus
Official
Unofficial
 Factors
 Conclusion
References
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3. INTRODUCTION
 Dissolution tests are one of the most commonly used tests in the
characterization of drugs and in the quality control of certain
dosage forms.
 During the late 1960s, it was accepted that dissolution data
should be determined by studying the rate at which dosage forms
allow their formulated drug to dissolve.
 Dissolution tests for seven products were introduced into the
USP 18.
 Dissolution tests become especially important if dissolution is
the rate-limiting step in drug absorption.
 Dissolution is considered today as one of the most important
quality control procedure performed on pharmaceutical dosage
forms.
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4. DISSOLUTION
 Dissolution is a process in which a solid
substance solubilizes in a given solvent i.e. mass
transfer from the solid surface to the liquid phase.
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Dissolution process of solid dosage Forms

5. DISSOLUTION TESTING
 Dissolution and drug release tests are in-vitro tests that measure
the rate and extent of dissolution or release of the drug
substance from a drug product, usually aq. medium under
specified conditions.
 It is an important QC procedure for the drug product and linked
to product performance in vivo.
 NEED FOR DISSOLUTION TESTING:
 Evaluation of bioavailability.
 Batch to batch drug release uniformity.
 Development of more efficacious and therapeutically optical
dosage forms.
 Ensures quality and stability of the product.
 Product development, quality control, research and application.
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6. 6
Dissolution testing apparatus from different
official Compendia

7. OFFICIAL
USP dissolution apparatus
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8. APPARATUS-1 (ROTATING BASKET)
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 DESIGN:
 Vessel: Made of borosilicate glass.
-hemispherical bottom
-Capacity 1000 ml
 Shaft: Shaft and basket made of SS 316.
-Cylindrical basket made of 22 mesh,
-Shaft must be rotate smoothly without
significant wobble.
 Speed :- 25-150 rpm
 Water bath:- Temp. Maintained at 37±0.5ºC
 USE: Tablets, capsules, delayed release dosage forms,
suppositories, floating dosage forms.

9. APPARATUS-2 (PADDLE)
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 DESIGN:
 Vessel: -Made of borosilicate glass.
-Semi hemispherical bottom
-Capacity 1000ml
 Paddle:-Made of Teflon coated and Stainless steel 316
-The metallic, suitably inert, rigid blade.
 Waterbath:- Maintains at 37±0.5°C
 Sinkers:-Platinum wire used to prevent
tablet/capsule from floating.

10.  DESIGN:
 Vessel: -Set of cylindrical flat bottom glass
vessels
-Set of reciprocating cylinders
-fittings of SS 316 and
screens made of nonsorbing or
non-reactive materials.
 Agitation type: -Reciprocating
-5-35 rpm
 Volume of medium:-200-250ml
 Water bath:- Maintain at 37±0.5°C
 USE: Tablets, beads, controlled and
extended release formulations
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APPARATUS-3(RECIPROCATING CYLINDER)

11.  DESIGN:
 Reservoir : -For dissolution medium
 Pump : -Forces dissolution medium through cell
Holding a sample
-Flow rate 10-100ml/min
-Laminar flow is maintained
-Peristaltic/centrifugal pumps are not
recommended
 Water bath:- Maintain at 37±0.5°C
 USE:
 Low solubility drugs ,micro particulates ,implants,
suppositories controlled release formulations
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APPARATUS-4 (FLOW THROUGH CELL)

12. CELL TYPES
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Tablets 12 mm Tablets 22.6 mm Powders / Granules Implants Suppositories /
Soft gelatin capsules

13. APPARATUS-5(PADDLE-OVER-DISK)
 DESIGN:
 Vessel:- Made of borosilicate glass, Capacity 1000ml
 Shaft :- Stainless steel 316 and Teflon coated.
 Stirring elements- rotating speed 25-50 rpm
 Sample holder:
-disk assembly that hold a product in such a way
that release surface is parallel with paddle
-Paddle is directly attached over disk assembly
-Samples are drawn between surface off the
medium and top of the paddle blade.
 Volume:900ml
 Temperature: 32 ± 0.5°C
 USE: Transdermal patches, ointments, floaters ,
emulsions etc.
 Modification: Disk design and volume
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14. APPARATUS-6(ROTATING CYLINDER)
 DESIGN:
 Vessel:- same as apparatus 1.
 Shaft :-Stainless steel 316, basket is replaced with cylinder is used
 Sample :- Mounted to inner porous cellulosic material and adheres to
cylinder.
- Dosage unit is placed in cylinder and release from side out.
 Water-bath: maintained at 32±0.5°C
 USE:
 Transdermal patches cannot be cut into small size.
 Solid dosage forms,
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15. APPARATUS-7(RECIPROCATING-DISK)
 DESIGN:
 Vessel:-Flat bottomed cylindrical vessel
-Volume of dissolution medium 900 mL.
 Sample : -Placed on disk shaped holders
 Agitation :-Reciprocation
-Reciprocating frequency 30 cycle/min
 Water-bath:-Maintain at 32 ± 0.5°C
 USE:
 Transdermal patches
 The assembly consists of a set of volumetrically calibrated solution
containers made of glass or suitable inert material, a motor , a drive
assembly used to reciprocate the system vertically.
 The samples are placed on the disk shaped holders using cuprophan
supports
 The test is carried out at 32°C.
 The reciprocating frequency is 30cycles/min.
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shaft
disk
dissolution medium
constant temp water bath

16. 16
Figure of Reciprocating Disk sample holder

17. 17
Figure of Reciprocating Disk sample holder

18. UNOFFICIAL METHODS
1. ROTATING/ STATIC DISK METHOD
 Developed by late Eino nelson and described by Levy and Sahli.
 In this method ,the drug is compressed in a non-disintegrating disc
without excipients.
 The disc is mounted in a holder so that only one face of the disc is
exposed to the dissolution medium.
 The holder and disc are immersed in medium and held in a fixed
position as in static disc method and rotated at a given speed in
rotating disc method.
 Samples are collected at predetermined times.
 Surface area of the drug through which dissolution
occurs is kept constant –intrinsic dissolution rate.
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19. 2.BEAKER METHOD:
 Reported by Levy and Hayes (1960).
 Dissolution medium, 250 ml of 0.1N HCl at 37°C placed
in a 400 ml beaker.
 Agitation by three blade polyethylene stirrer,5cm diameter and rotates at 60 rpm.
 Stirrer immersed to a depth of 2.7 cm in medium and in the center.
 Tablets are placed in a beaker and test was carried out.
 Samples are removed and assayed for the content.
3.FLASK STIRRER METHOD
 Developed by Poole (1969).It includes RBF and a stirring element similar to that
of beaker method.
 RBF used to avoid the formation of moulds of particles in different positions on
the flat bottom of a beaker.
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20. 4.PERISTALSIS METHOD:
 To stimulate hydrodynamic condition of GIT tract in an in-vitro
dissolution device.
 It consists of rigid plastic cylindrical tubing fitted with septum and rubber
stopper at both ends.
 Dissolution chamber consists of a space between septum and lower
stopper.
 Dissolution medium is pumped with peristaltic action through the dosage
form.
5.ROTATING BOTTLE METHOD:
 It consists of rotating rack to hold sample drug products in bottles and
they are capped tightly & rotated in 37°C temperature bath.
 Sample are decanted through a 40 mesh screen and residue are assayed.
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21. 6.DIALYSIS METHOD:
 Cell consist of 32mm inflated membrane.
 Plugged at the lower end by tight fitting cylindrical perspex box.
 Upper end of the tube held by thin perspex ring inserted into the tube
and secured by an elastic band.
 The cell suspended , from the arm of the tablet disintegration
apparatus and containing the dosage form in 150ml of distilled water
at 37°C.
 The cell is raised or lowered 30times a min, into 150ml of distilled
water at same temperature.
 Agitation by slight flexing and stretching of the dialysis membrane as
it enters and leaves the bath. Rotated at 60rpm.
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22. Diffusion cell
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23. FACTORS RELATED TO THE APPARATUS
 Size and shape
 Agitation device
 Speed of agitation
 Temperature
FACTORS RELATED TO DISSOLUTION MEDIA
 pH of dissolution media
 Surface tension
 Viscosity
 Volume
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24. CONCLUSION
By studying various factors influencing the rate of
dissolution, we can optimize the different properties of
the formulation. By conducting dissolution studies we
can know the batch to batch reproducibility. We can
estimate the solubilty profiles of the drug. The best
available tool today which can atleast quantitatively
assure about the biological availability of drug from its
formulation is its in vitro dissolution.
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25. REFERENCES
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1. Brahmankar D.M.; Jaiswal S.B., Biopharmaceutics and
Pharmacokinetics- A Treatise, Vallabh Prakashan, New delhi,
India. (2009) pp 325-329.
2. Aulton M.E., Pharmaceutics The Science of Dosage Form
Design, 2nd Ed.; Churchill Livingstone. (2011) 20-25.
3. Encyclopedia of Pharmaceutical Technology, Vol-I third
edition, Edited by James Swarbrick pp 907-909.
4. Remington- The Science and Practise of Pharmacy, Vol- 1, 21st
edition, Lippincott Williams and Wilkins. pp 662-680.
5. United States Pharmacopeia and National Formulary
,United States Pharmacopeial Convention Inc., Rockville,

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YOU