Calibration of Dissolution Test Apparatus

PROCEDURE :

The apparatus consist of constant temperature water bath made of transparent acrylic. The round bottom glass vessels are placed equidistant inside the bath. The jar have acrylic lids which allow passing of stirrer shaft. The shafts are suspended from the top. The stirrers are controlled by microprocessor.

The bath temperature is controlled by microprocessor based controller within + 0.50C. Additional features of apparatus are microprocessor based digital timer. This is provided with audio alarm which operates as per pre-set time.

PRECAUTION:

Ensure that the power supply to the instrument is switched OFF before cleaning.

Clean the equipment with a clean dry cloth every day to remove the moisture.

Do not start the heater if there is no water in the tank up to the mark level.

Fill the water bath with distilled water only.

Do not pull or force the paddle or basket.

Do not hold the stirrer while in operation.

OPERATION:

Do not operate Heater without sufficient water in the bath.

Always maintain the water level before operating the system.

Switch on the power switch.

Attach Basket/Paddle and  ensure all parts are fitted properly.

Fill all the six glass vessels as per specified media, mentioned in test procedure.

After the fixing of  Basket/Paddle, set the following parameter as per procedure given,                1.   TEMPERATURE SETTING                2.   TIME  SETTING                3.   RPM SETTING

TEMPERATURE SETTING:

Switch “ON” the mains.

To set the temperature of the water bath, Press MODE switch.

Indicator will indicate either SET temperature Screen says bath temperature or -0.5 OFFSET adjustment screen.

If it is in SET temperature mode, adjust the  temperature Setting by ▲  UP OR ▼ DOWN  arrow.

When UP/DOWN arrow switch is pressed  initially, it will change at slow rate and after 10 counts it will change faster.

Once the setting is over, release the switch.

To go to OFF SET Mode, Press MODE switch again.

Display will show OFFSET □ – 0.5 adjustment screen, and if it does not show 0.5 then adjust the OFFSET by  UP/DOWN key.

To come back to the bath  temperature indication, press ENTER switch.

After some time  temperature Controller maintains  temperature close to set  temperature  inside the bath.

Function of ‘OFFSET’ is to correct the difference between SET temperature and ACTUAL  temperature, depending upon load inside the bath.

TIME  SETTING:

To set the required Time press ‘SET’ switch.

Yellow coloured LED will  glow.

Adjust the set time by UP ▲ and DOWN ▼ switches.

Once the setting is over, press RESET switch so as the time indicates  00Hour : 00Minutes

Press START switch.

Green coloured LED will glow and  Timer will start counting the Time.

When the actual time equals the set time, red coloured LED will glow and machine will give long beep.

Press ‘STOP’ switch to stop the beep.

Reset switch is provided to Reset Actual Time to 00Hr : 00Min.

If the ‘AUTO/ON’ switch is in ‘AUTO’ mode, mean  Basket/Paddle will switch off with alarm after the finish.

RPM SETTING:

RPM varies from 25 to 160 per minutes

Press START Switch.

Start LED will glow and all Basket/Paddle will start rotating and digital display will show the speed of rotation.

Press ▲ & ▼ switch to decrease or increase the speed.

Press STOP switch to stop all the  Basket/Paddle.

Basket/Paddle will start rotating in the medium at set RPM provided in stirrer START mode.

After required temperature, time as per the monograph mentioned in pharmacopoeia / test procedure are set and required  temperature in the bath is maintained, bring the stirrer down using DOWN ▼ key.

The stirrer unit will automatically stop at the required height (i.e. paddle / basket will be 25 mm above the jar bottom)

Start the stirrer by using start key.

Once the set temperature attain put the tablets/ capsules in the glass vessels .

Cover the glass vessels with lids.

After the completion of specified run time, the instrument will give long beep sound indicating that the test is completed, then proceed the further as per specified method for analysis.

At the time interval specified  in individual monograph, withdraw a sample from a zone midway between the surface of the dissolution medium and the top of rotating basket/ paddle not less than 1 cm from the glass vessels wall with the help of cannulae.

Withdraw the sample within specified time.

Clean all the glass vessels and stirrer after completion of the analysis and switch OFF the instrument.

CALIBRATION:

A ) MECHANICAL CALIBRATION (Verification of Physical Parameter)

DISTANCE

1.   Fix the baskets/paddles to the instrument.

2.   Bring down the stirrer  using DOWN ▼ key until it  stops automatically .

3.   Measure the distance between the inside bottom of bowl and the basket/        paddle with the help of scale and write in calibration format.

4.  Acceptance criteria :        Observed distance must be within 25 mm  + 2 mm .

REVOLUTION PER MINUTES

1. Set the RPM to 50 and 100 respectively.

2.  Record the RPM manually by  stop watch  and write in calibration format.

3.  Acceptance criteria :        For      50 RPM   + 2 RPM                   100 RPM + 4 RPM

TEMPERATURE

1.  Set the temperature at 350C,370C and 400C  as mentioned in point No.5.3.

2.  Measure the temperature of dissolution media by calibrated thermometer and

write in calibration format.

3. Acceptance criteria : Observed temperature must be within  + 0.50C than set temperature.

TIME

1.  Set the time at 30 min. and 60 min. respectively as mentioned in point No.5.4.

2.  Note the time by stop watch and write in calibration format.

3.  Acceptance criteria : Observed time must be within  + 1 min. than set time.

B ) CHEMICAL CALIBRATION (Apparatus Suitability Test)

BY USING  PREDNISONE 10 MG PER TABLETS(Disintegrating Type)

1.   Ensure that the mains of the instrument and supply is ON.

2.   Set the time program for 30 minute, temperature 370C + 0.50C and for 50 RPM.

3.    Fit the paddle apparatus.

4. Dissolution media :  500 ml Distilled water

Heat the media with gentle stirring, to about 450C, immediately filter the media under vacuum using membrane filter.

5. Standard

Weigh accurately about 10 mg of prednisone reference standard (already dried on 1050C for 3 hours) in 50 ml volumetric flask and dissolve in 5 ml of ethanol.

Dilute 1 ml of the above solution to 20 ml with dissolution media.

6.Sample

After achieving the temperature place 1 tablet in each glass vessel.

After the completion of time program withdrawn sample solution from each glass vessel by cannulae and filter through the whatman filter no. 41 in individual tubes.

Discard first 50 ml of solution.

Take 10 ml of filtrate and dilute up to  20 ml  with dissolution media.

8. Take the absorbance at 242 nm using distilled water as a blank and write in calibration format.

9.  Also carry out above procedure by changing the basket apparatus.

10. Affix calibration label on instrument after calibration.

11. Acceptance criteria :

Limit for the prednisone tablet decided from the certificate of this lot.