Compendial and Alternative method of dissolution/Dissolution Apparatus

1. DISSOLUTION APPARATUS
Presented by:
Moidul Islam
M. Pharm 2nd Sem
Pharmaceutics
ISF College of Pharmacy.

2. Type Method name Specification Dosage form
1 Basket Vessel : made up of transparent, inert material
(borosilicate glass) capacity : 1000ml
Shaft : SS316, water bath temp. 37±0.5 °C, speed 50-
100rpm, Disadvantage : formulation may clog to 40
mesh screen
Tablets, capsules
2 Paddle water bath temp. 37±0.5 °C, stirring element : made
up of Teflon for laboratory purpose SS316 speed : 25-
100rpm, Disadvantage : floating dosage form require
sinker positioning of tablet
Tablets, capsules, modified drug
products, suspensions
3 Reciprocating cylinder Vessel : cylindrical flat bottom glass vessel, speed : 6-
35 cycle/min., vol. of disso. Fluid : 200-250ml, water
bath temp. 37±0.5 °C,
Extended-release drug products
4 Flow through cell Flow rate : 4-32 ml/min. temp. 37°C, 6 samples are
tested,
Drug products containing low
water-soluble drugs
Compendial method of dissolution

3. Type Method name Specification Dosage form
5 Paddle over disc Vessel & shaft : same as paddle apparatus, rotation
speed : 25-50 rpm, temp. 32±0.5 °C, vol. 900ml,
Transdermal drug products
6 Cylinder modified from the basket method (Apparatus 1), In
place of the basket, a stainless-steel cylinder is used to
hold the sample, temp. 32±0.5 °C,
Transdermal drug products
7 Reciprocating
disk
Vessel : flat bottomed cylindrical vessel, sample :
placed on the disk shaped holder, reciprocating
frequency : 30 cycles/min., temp. 32±0.5 °C,
Extended-release drug products
Compendial method of dissolution

4. Apparatus 1 : basket type

5. Characteristics USP BP IP
Basket shaft 6.3-6.5 or
9.4-10.1mm
6.3-6.5 or
9.4-10.1mm
9.7 ± 0.3 or
6.4 ± 0.1mm
Basket material
(stainless steel)
Type 316 Type 316 Type 316
Vent hole 2.0 ± 0.5mm 2.0 ± 0.5mm 2.0mm
Retention spring 3 tangs 3 tangs 3 tangs
Clear opening 20.2 ± 0.1 mm 20.2 ± 1.0 mm 22.2 ± 1.0 mm
Wire diameter 0.25mm 0.25-0.33mm 0.254mm
RPM 50-100 100 100
Height of screen 27.0 ± 1.0mm 27.0 ± 1.0mm 27.0 ± 1.0mm
Height of upper cap 5.1 ± 0.5 mm 5.1 ± 0.5 mm 5.1 ± 0.5 mm
Total height of basket 37.0 ± 3.0 mm 37.0 ± 3.0 mm 36.8 ± 3.0 mm
DETAILS OF CONSTRUCTION OF BASKET APPARATUS

7. Characteristics USP BP IP
Vessel height 160-210mm 160mm 160 ±8 mm
Paddle shaft diameter
(before coating)
9.4-10.1 mm 9.4-10.1 mm 9.75 ± 0.35 mm
Blade upper chord 74.5-75.0 mm 74.5-75.0 mm 74.5-75.0 mm
Blade lower chord 42 ± 0.1 mm 42.0 mm 42.0 mm
Height 19.0 ± 0.5 mm 19.0 ± 0.5 mm 19.0 mm
Radius disk 41.5 ± 1 mm 41.5 mm 41.5 mm
Thickness of blade 4.0 ± 1 mm 4.0 ± 1 mm 4.1 ± 1 mm
Device distance from
bottom
25 ± 2 mm 25 ± 2 mm 25 ± 2 mm
DETAILS OF CONSTRUCTION OF PADDLE TYPE APPARATUS

8. Characteristics USP BP
Glass vessel height
(mm)
180 ± 1 180 ± 1
Glass vessel diameter
(mm)
47 ± 1.4 47 ± 1.4
Glass reciprocating
tube length (mm)
100 ± 1 100 ± 1
Glass reciprocating
tube dia. (mm)
23-26 23-26
Tube air hole
diameter (mm)
3.9 ± 0.1 3.9 ± 0.1
Evaporation cap
height (mm)
66.8 ± 1 66.8 ± 1
Evaporation cap
diameter (mm)
50.8 ± 1 50.8 ± 1
Cap air hole 3.9 ± 1 3.9 ± 1
DETAILS OF CONSTRUCTION OF RECIPROCATING CYLINDER

9. Characteristic USP BP
Sieve 40 mesh
diameter
0.2 0.2
Internal diameter 20 ± 0.2 20 ± 0.2
Outer diameter 22.5 ± 0.2 22.5 ± 0.2
Angle 40 ± 1° 40 ± 1°
Tablet holder
height
6.5 mm 6.5 mm
Tablet holder
thickness
0.5 mm 0.5 mm
Tablet holder
width
7.5 mm 7.5 mm
DETAILS OF CONSTRUCTION OF FLOW THROUGH CELL

10. PADDLE OVER DISC ROTATING CYLINDER

11. Alternative method of dissolution
Method Specification Dosage form
Rotating bottle
method
consists of a rotating rack that holds the sample drug products in bottles, The
bottles are capped tightly and rotated in a 37°C temperature bath, disadvantage
: procedure is manual and tedious
controlled release beads
Intrinsic
dissolution
method
rigid plastic cylindrical tubing fitted with a septum and rubber stoppers at both
ends, The apparatus is placed in a beaker containing the dissolution medium,
characterization of the
crystallized forms and
polymorphs of pure
drugs and drug
formulations
Peristalsis method It consists of a rigid plastic cylindrical tubing fitted with a septum and rubber
stoppers at both ends, The dissolution chamber consists of a space between the
septum and the lower stopper, apparatus is placed in a beaker containing the
dissolution medium,
Diffusion cell Franz diffusion cell is used for characterizing drug permeation through a skin
model, The skin is mounted on the Franz diffusion cell system, The drug product
(eg, ointment) is placed on the skin surface and the drug permeates across the
skin into a receptor fluid compartment that may be sampled at various times,
used for comparing in vitro drug release profiles and skin permeation
characteristics.
Topical drug product

12. Franz diffusion cell system