DISSOLUTION SYSTEMS FOR UV/VISINTRODUCTION
All of our UV-VIS on-line systems are based on the ‘continuous flow’ method which is understandably the most popular approach to automated Tablet Dissolution Testing. Such systems are simple, clean, easy to set up and maintain.
In the case of Agilent, two dissolution software options are available. Our standard CDS software or Agilent's own Chemstation Dissolution software based on the 8453 Spectrometer (special driver required for this option). In this technique, media from each individual test vessel is circulated continuously through each of a series of flow cells (nominally 6-8) located in the cell compartment of a suitable UV/VIS Spectrophotometer by means of a peristaltic pump.
A cell changer mechanism moves each cell in turn into the light beam of the spectrophotometer and the absorbance of each solution is measured. Measurements are made at user-specified intervals. The whole system is controlled by an external PC whose software collects and analyses the results. All our UV/VIS Continuous Flow Systems are ‘ready-to-run’ and are particularly easy to use, the operator being guided throughout the performance of the test by a series of on-screen prompts.
SYSTEM COMPONENTS
The system comprises four main elements:
- 1) Dissolution Tester
Choose our DIS 6000 or DIS 8000 or our latest model: DIS-EMC
- 2) Ismatec 8-Channel Pump
A relatively low cost 8-channel pump operating on the peristaltic principle, the Ismatec IPC-8 is the ideal pump for incorporation into the conventional dissolution system.
When used with 2.79 mm bore tubes, the pump has a range of 1 to 37 ml/min per line. The flow rate is adjusted by altering the speed of the pump - a setting of 55% will for example give a flow rate of approx. 20 ml/min per line which is suitable for most conventional dissolution applications (USP Methods 1, 2, 5 and 6).
The speed and direction of the pump are adjusted either manually from the pump’s in-built controls (via up and down keys linked to a LCD screen) or via its RS232 Interface directly by the Dissolution Software.
The pump is also fitted with a ‘maximum speed override’ button which when pressed causes the pump to run at maximum speed, a useful facility for flushing lines when cleaning, etc. The unit is extremely compact measuring only 220 mm long x 150 mm wide x 130 mm high.
- UV/VIS Spectrophotometer
In the case of Agilent, 2 Dissolution Software options are available. Our Copley CDS Software or Agilent's own software based on the 8453 Spectrometer.
A wide range of spectrophotometers is now available for dissolution applications.
The Windows based software will interface with most commercially available spectrophotometers including Beckman, Cecil, Perkin Elmer and Shimadzu using the interface facility provided for this purpose.
All packages quoted include bath, peristaltic pump, spectro-photometer, 8 cell programmer, 8 x 10 mm cells, peristaltic pump, tubing kit, PC with dissolution software and IQ/OQ documentation.
For highly absorbing drug formulations, the systems can be supplied with 1, 2 or 5 mm pathlength flow cells in place of the standard 10 mm giving effective dilution ratios of 10:1, 5:1 and 2:1 respectively.
The choice of spectrophotometer will depend to a large extent on cost and the degree of sophistication required i.e., single beam, double beam, etc. Some examples are given on the right.
Model numbers change frequently. Please consult our technical staff for up-to-date details.
- Dissolution Software (incl. Interface, PC and Printer)
Our Dissolution Software (CDS) is a comprehensive and versatile full colour software package for the automatic ‘real-time’ generation of tablet dissolution results. The software assumes complete control over all of the system components via the interface facility provided for this purpose.
Key features include:
- 21 CFR Part 11 compliant (including electronic signatures)
- User friendly graphical interface for system set-up
- Provision for simultaneous or staggered starts
- ‘Real time’ display of dissolution profiles and results
- Easy method construction
- Four standardisation methods
- Validation Log of temperature and speed during test
- Five results formats (Abs, Conc, % , mg or time to % dissolved)
- Graphic display of individual or overlaid dissolution curves
- Graphic display/highlighting of ‘out of limits’ results
- Powerful post-run screen editing facilities
- User defined reporting procedures
For more information: 