💊 Dissolution Test for Solid Dosage Forms

Pharma & Cosmetics Ph. Eur. 2.9.3

Overview

STATUS (as of 06.11.2026). Ph. Eur. 2.9.3 “Dissolution test for solid dosage forms” — a general chapter of the European Pharmacopoeia. Edition 12 is in force (supplement 12.3 from 01.07.2026); edition 13 (supplement 13.1) applies from 01.01.2027, and its list of new, revised and corrected texts does not include chapter 2.9.3. The pharmacopoeia text is not free — the description is based on the text harmonised in the Pharmacopoeial Discussion Group (PDG, document Q-01 “Dissolution”), adopted by Ph. Eur. 2.9.3, JP 6.10 and USP <711>, and on ICH Q4B Annex 7(R2).

SCOPE. The test determines compliance of oral dosage forms with dissolution requirements; a dosage unit is 1 tablet, 1 capsule or the amount specified in the monograph. The text contains procedures for immediate-release, extended-release and delayed-release dosage forms.

APPARATUS. Apparatus 1 (basket) and apparatus 2 (paddle): cylindrical vessel with a hemispherical bottom and a capacity of 1 litre (height 160–210 mm, inside diameter 98–106 mm), medium kept at 37.0 ± 0.5 °C, rotation speed maintained within ±4 %, shaft axis not more than 2 mm from the vessel axis, distance of the basket or paddle from the bottom 25 ± 2 mm. A floating dosage form may be weighted (e.g. a few turns of wire or validated sinkers). Apparatus 3 (reciprocating cylinder): dip rate within ±5 %, stroke 9.9–10.1 cm — not accepted by the Japanese Pharmacopoeia. Apparatus 4 (flow-through cell): pump 240–960 ml/h, standard flow rates 4, 8 and 16 ml/min (±5 %), cells of 12 and 22.6 mm diameter. The suitability of the assembly is checked by conformity to dimensions and tolerances and periodic monitoring of the volume and temperature of the medium, rotation speed, dip rate and flow rate.

PROCEDURE (apparatus 1 or 2, immediate-release form). The stated volume of medium (±1 %) is placed in the vessel, equilibrated to 37.0 ± 0.5 °C, the thermometer is removed, 1 unit is placed without air bubbles and the apparatus is started immediately. Aliquots are withdrawn at the stated times (tolerance ±2 %) from a zone midway between the surface of the medium and the top of the basket or blade, not less than 1 cm from the vessel wall; with several time points the withdrawn volume is replaced with fresh medium at 37 °C or accounted for in the calculation. Aliquots are filtered immediately (unless filtration is shown to be unnecessary) through an inert filter. A buffered medium is adjusted to the specified pH ±0.05; dissolved gases, if they influence the result, are removed before the test.

EVALUATION (immediate-release form). S1 — 6 units, none below Q + 5 %; S2 — another 6, mean of 12 ≥ Q and none below Q − 15 %; S3 — another 12, mean of 24 ≥ Q, not more than 2 below Q − 15 % and none below Q − 25 %. Q is the amount of dissolved active ingredient specified in the monograph, as a percentage of the labelled content. Extended-release forms are evaluated in levels L1–L3, delayed-release forms in the acid stage (A1–A3) and buffer stage (B1–B3).

INTERCHANGEABILITY (ICH Q4B Annex 7(R2)). Ph. Eur. 2.9.3, JP 6.10 and USP <711> are considered interchangeable for the basket, paddle and flow-through cell apparatus — with exceptions: not for media with enzymes, enteric-coated (delayed-release) forms, vessels larger than 1 litre or Interpretation 2 of the Japanese Pharmacopoeia; medium, stirring rate, sampling times and sinkers are specified and justified in the application dossier, as are the acceptance criteria.

PROFILE COMPARISON (ICH M9). For a waiver of bioequivalence studies based on the Biopharmaceutics Classification System (BCS) dissolution profiles are compared: paddle apparatus 50 rpm or basket 100 rpm, 900 ml of medium or less, 37 ± 1 °C, at least 12 units, buffers of pH 1.2, 4.5 and 6.8, no organic solvents or surfactants; profiles are similar when the factor f2 ≥ 50. The dissolution test itself is not a bioequivalence study.

WHAT WE DO NOT GIVE HERE. The volume of medium, stirring rate, sampling times and the value of Q are not given in the general chapter — they are set by the individual monograph or the application dossier. Nor do we give the method for determining the active ingredient (the text requires “a suitable assay method”) or local differences of the Ph. Eur. text from the harmonised text, because the pharmacopoeia text is not freely available.

Method principle

The dosage unit is placed in an apparatus with medium — in a rotating basket, at the bottom of a vessel with a paddle, in a reciprocating cylinder or in a flow-through cell. At the stated times aliquots of the medium are withdrawn and filtered, and the active ingredient is determined in them by a suitable method. The medium is kept at 37.0 ± 0.5 °C. The result is expressed as the amount dissolved as a percentage of the labelled content and evaluated in stages according to the acceptance tables.

Applications

• Testing compliance of oral solid dosage forms with monograph requirements — immediate-release tablets and capsules (stages S1–S3)
• Extended-release forms — several time points expressed in hours, evaluation in levels L1–L3
• Delayed-release (enteric) forms — acid stage in 0.1 N hydrochloric acid for 2 h and buffer stage pH 6.8
• Comparison of dissolution profiles (factor f2) for a BCS-based waiver of bioequivalence studies (ICH M9)
• Registration dossiers in the ICH regions — interchangeability of Ph. Eur. 2.9.3, JP 6.10 and USP <711> under the conditions of ICH Q4B Annex 7(R2)

Key parameters

Standard

Standard number

Ph. Eur. 2.9.3 (European Pharmacopoeia, 12th edition)

Title (PL)

Badanie uwalniania z postaci stałych (tłumaczenie robocze)

Title (EN)

Dissolution test for solid dosage forms

Step-by-step procedure

1. Apparatus check

   Dimensions and tolerances of the apparatus and periodically: volume and temperature of the medium, rotation speed (apparatus 1 and 2), dip rate (apparatus 3), flow rate (apparatus 4).

2. Preparation of the medium

   Medium according to the monograph; buffer to pH ±0.05; if dissolved gases influence the result — their removal before the test.

3. Filling and temperature equilibration

   Stated volume of medium (±1 %) in the vessel, equilibration to 37.0 ± 0.5 °C, removal of the thermometer.

   🌡 Temperature: 37.0 ± 0.5 °C

4. Introduction of the unit

   One dosage unit per vessel, without air bubbles on its surface; in apparatus 1 — into a dry basket, in apparatus 2 — allowed to sink to the bottom (a floating form is weighted); the apparatus is started immediately at the specified rate.

5. Withdrawal of aliquots

   At the stated times (±2 %), from a zone midway between the surface of the medium and the top of the basket or blade, not less than 1 cm from the wall; vessel covered, temperature checked at suitable times.

6. Volume replacement

   With several time points the withdrawn volume is replaced with fresh medium at 37 °C or — where shown to be unnecessary — the volume change is accounted for in the calculation.

7. Filtration and assay

   Aliquots are filtered immediately through an inert filter (unless filtration is unnecessary) and the active ingredient is determined by a suitable method.

8. Evaluation

   Immediate release — stages S1, S2, S3 (acceptance table 1); extended — levels L1–L3; delayed — acid stage A1–A3 and buffer stage B1–B3 (Q 75 % by default). Testing continues to the next stage only if the earlier one did not show conformity.

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• Hydrochloric acid and sodium hydroxide for preparing media and adjusting pH — handling according to the safety data sheets for the given concentration
• Active ingredients and reference standards — handling according to the safety data sheet of the substance

Frequently asked questions