ppt
TRANSCRIPT
Seminar On
In vitro dissolution testing models
Presented byMr. Prashant Gaikwad
Under Guidance ofDr. A Srinatha
• The Usp-NF provides several official methods for
carrying out dissolution test.
• The selection of a particular method for a drug is
usually in the monograph for a particular drug product.
Apparatus Name Drug product
Apparatus 1 Rotating basket Tablets
Apparatus 2 Paddle Tablets, capsules, suspension
Apparatus 3 Reciprocating cylinder
Extended release
Apparatus 4 Flow cell Low water soluble drug
Apparatus 5 Paddle over disk Transdermal
Apparatus 6 Cylinder Transdermal
Apparatus 7 Reciprocating disk Extended release
Rotating bottle Non-USP-NF Extended release (beads)
Diffusion cell (Franz)
Non-USP-NF Ointments, creams, Transdermal
Based on the absence or presence of sink conditions dissolution apparatus are 3 types
1. Closed-compartment apparatus
2. Open- compartment apparatus
3. Dialysis apparatus
Factors must be considered in design of dissolution tests:1. Factors relating the dissolution apparatus
2. Factors relating to the dissolution fluid
3. Process parameter e.g. method of introducing dosage form, sampling techniques, changing dissolution fluid etc.
Apparatus 1 (Rotating basket)
The assembly consist
1. A covered vessel
• Cylindrical, hemispherical bottom
• Diameter is 98-106 mm & normal capacity 1000 ml
2. Motor, metallic drive shaft
• Fabricated of stainless steel type
3. Cylindrical basket
• Gold coating 0.0001 inch (2.5 µm)
Apparatus 2 (Paddle)
•The assembly is same as apparatus 1 except that a paddle formed from a blade & a shaft is used as stirring element.
•The metallic blade & shaft comprise a single entity that may be coated with a suitable inert coating.
Apparatus 3 (reciprocating cylinder)
The assembly consist:1.Set of cylindrical, flat bottomed glass vessels2.Set of reciprocating cylinders3.Stainless steel fittings (type 316 or equivalent)4.Polyproylene screens5.Motor & drive assembly
Apparatus 4 (Flow through cell)• The assembly consist of
– Reservoir & pump for dissolution medium– A flow through cell– A water bath
•The flow through cell is transparent & inert mounted vertically with filters.•Standard cell diameters are 12 & 22.6 mm. •The bottom cone usually filled with glass beads of 1 mm diameter.•Tablet holder used for positioning special dosage form e.g. inlay tablets.
Cell Types
Tablets 12 mm Tablets 22.6 mm Powders / Granules Implants Suppositories / Soft gelatin capsules
Flow-Through Apparatus
Apparatus 5 (Paddle over disk)•The assembly consist-Cylindrical vessel-Motor drive shaft-Paddle-Stainless steel disk
•Disk- minimize “dead volume” between disk assembly & bottom of vessel
•Disk- holds the system flat & release surface parallel with the bottom of paddle blade.
Apparatus 6 (Reciprocating cylinder)
• Use assembly from
apparatus 1
• Replace basket with
stainless steel cylinder
• Dosage unit placed on the
cylinder
Apparatus 7 (Reciprocating disk)• This apparatus consist
– Containers
– Set of disk shaped sample
holder
– Motor & drive assembly
• Reciprocate at frequency of
about 30 cycles/min.
Rotating Bottle
• Used for controlled release beads
• Consist a rotating racks that holds sample in bottles
• Bottles are capped tightly & rotated in 37ºC water
bath.
• At various time, samples are collected from bottle,
decanted from 40 mesh screen & residues are
assayed.
Diffusion cells• Used for topical &
transdermal drug products.
• Franz diffusion cell is static diffusion system used for characterizing drug permeation through skin model.
• The source of skin may be cadaver or animal skin.
Interpretation• The amount of drug dissolved within a given time period (Q)
is expressed as a percentage label content.Acceptance Table:
Stage Number tested
Acceptance criteria
S1 6 Each unit is NLT Q +5 %
S2 6 Average of 12 units (S1+S2) is equal to or greater than Q, & no unit less than Q - 15%
S3 12 Average of 24 units (S1+S2+S3) is equal to or greater than Q, NMT 2 units are less than Q- 15% & no unit is less than Q- 25%
References• The United States Pharmacopeia, NF-18, Asian Edition, 1995,
Page no. 1791-1799
• Leon Shargel, Applied Biopharmaceutics & Pharmacokinetics,
5th Edition, 2005, Page no. 424-430
• Brahmankar & Jaiswal,Biopharmaceutics & Pharmacokinetics
A Treatise, Vallabh Prakashan, Page no. 291
• http://www.labplus.co.kr/tech/tech_note.asp?not_no=270
• http://www.pharmacopeia.cn/v29240/usp29nf24s0_c711h.html
• http://apps.who.int/phint/en/d/Jb/7.5.6.html
• http://www.pharmacopeia.cn/v29240/usp29nf24s0_c724h_viewall.html