Principle of Dissolution Test Apparatus
Dissolution is the analysis process in which the analyzed substance forms a solution. In this testing measurement of the content and rate of dissolving in the solution from a dosage form, such as a tablet, capsule, ointment, etc. is done. The rate of dissolution of every drug is very significant for its bioavailability and therapeutic effectiveness when used by humans. The calibration of the dissolution test apparatus is the main function of the dissolution process in the quality control department.
The evaluation of the dissolution of drug products can be done properly only when the testing procedure is well-calibrated with the apparatus. The standardization and calibration of dissolution test apparatus lead to the manufacture of a quality product.
Principle of Dissolution Test Apparatus
Dissolution testing is usually done to provide specific in-vitro drug release information from some dosage form, the information is used in quality control analysis, product development, and possible effects on human consumption.
Three main objectives of dissolution testing are very important in the pharma industry:
(i) To set formulation and optimization decisions: Usually during product development in the company, for those products whose dissolution performance is an important quality attribute, the product formulation and the manufacturing process are reprocessed to achieve specific drug release in vitro by dissolution testing.
(ii) Equivalence decisions: While generic medicine development or during implementing formulation changes in any product, the similarity of in-vitro dissolution profiles between the reference product and its generic version is one of the key requirements for regulatory approval decisions.
(iii) Product compliance and release decisions: Dissolution testing is necessary as per any pharmacopeia followed for a particular product, dissolution results are very Important criteria followed before product release decisions.
Dissolution Apparatus System Operation :
1 Lift the stirrer unit.
2 Insert the shaft rod as per the method selected.
3 Place the Test Sample in the Test Vessel. Start.
4 Press the Down Arrow key from the front panel to lower down the stirrer unit. The stirrer unit will adjust automatically to the required height depending on the test method selected.
PROTO : ## STEP : ##
ELAPSE TIME (T) : ### : ## : ##
RPM : ### BATH : ##.#
EXT : ##.# main-screen
5 Press the START key from the front panel to start the test. The instrument will now show the
6 Run Time Screen.
7 The Run Time Screen will display the Protocol Running (refer to Idle Screen), The Step No. (Refer to Option (c) in Parameter Setting), The Elapsed Sampling Time for that particular Step (Refer to Option (a) in Parameter Setting) and actual Bath Temperature are measured by the external Probe (If Connected). The RUN LED on the Front Panel will glow indicating the instrument’s RUN Condition.
Calibration: Calibration Includes the following parameters
(1) RPM of all the shafts
(2) The temperature of all the beakers.
1. RPM Setting :
In this parameter rotation per minute of the shaft is set & checked by a stopwatch.
SET RMP = 150 ◄▼►┘
STIRRER
ON OFF RPM-screen
2. Setting of Spindle RPM :
Step 1 : Press RPM key from the front panel a RPM screen will be displayed.
Step 2 : Using UP / Down / Digit scroll key set the required RPM.
Step 3 : Press Enter key to register the value and to come out of the RPM mode.
SET TEMP = 37.5 0C ◄▼►┘
HEATER
<ON> OFF Temperature Screen
Heater ON/OFF
Step 1 : For the Heater ON/OFF Press the TEMP key from the front panel a Temperature screen will be displayed.
Step 2 : Press F1 key for the heater to be ON or the F2 key for the heater to be OFF from the front panel.
Step 3: Press the Enter key to come out of the TEMP Mode. An Idle screen will be displayed.
Indication :
a>If the Temperature Controller has started then the ON LED on the front panel and ETC – 11L will glow.
b> IF HEATER ON then the circulating pump will start by default.
PROTOCOL = 15 ▼◄
RPM: ###
BATH = 37.5 EXT = 37.5
Prepare Jar Temp.
Idle screen when heater ON
Idle Screen Displayed :
If HEATER ON then the BATH and EXT probes on the idle screen will show a simultaneous rise in temperature and will attain up to the set temperature.
If HEATER OFF then BATH and EXT probe displayed on the screen will be the room temp or the surrounding temperature.
Calibration frequency: Once in a month.
Summary
According to USP, the dissolution test apparatus ideally have 4 standardized apparatus: basket, paddle, reciprocating cylinder, and flow-through cell. The use of a particular standardized apparatus is given in a specific monograph of the drug analyzed. The calibration of the dissolution test apparatus may be different as per the different pharmacopeia IP/BP/USP.
References:
- PROTOCOL: IP DISSOLUTION APPARATUS CALIBRATOR, PREDNISONE TABLETS RS- [IPC-Indian Pharmacopoeia]
- Calibration of Dissolution Test Apparatus- usp.org/ghana [CePAT]
