The Rainbow is a powerful tool for highly accurate dissolution analysis without the high cost, extensive maintenance, operator involvement, and slow turnaround time of conventional methods. UV-based spectroscopy has been adopted for dissolution testing by R&D, manufacturing, and QC laboratories worldwide.
The Rainbow employs a patented process for data acquisition and presents it in real-time. This enables the user to view the collection of data points from each probe as the data are collected. No need for external programs or calculations after the experiment. When the data collection is done, you’re done!
The in situ UV monitoring supersedes traditional HPLC or flow-injection systems by eliminating the problems of operator error, complicated mechanical sipping devices, clogged filters, sample adhesion to tubing walls, wasted bench space, expensive consumables and clean-up. We pipe the light, not the liquid! Equipped to collect data from the very start of the experiment to several days later, the Rainbow monitor is ideal for both rapid-release and extended release solid dosage forms.
Small, Clean, Quiet
The Rainbow fits nicely on your lab bench right next to the dissolution bath. Since the Rainbow pipes the light and not the liquid, it does not generate any waste of its own. 
In fact, the only cleaning required is a quick rinse of the probes. Using the accompanying Indigo™ software, the Rainbow is easy to operate, requiring almost no maintenance, as there are no moving parts in the system.
UV in situ Dip Probes
The Rainbow utilizes dip-type UV probes (6 to 8 per monitor) to measure the amount of active pharmaceutical ingredient (API) released from a solid dosage form. These probes are suspended at the USP sampling position in the dissolution vessels and reside in situ for the duration of the test. 
Constructed of stainless steel, the probes have interchangeable quartz mirror tips offering path lengths of 1, 2, 5, 10, and 20 mm. The probes are sturdy, durable, and may be used in most dissolution media and all baths.
Security in the QC Environment
For GMP and QC environments, the optional IndigoSAM™ software adds a full suite of security tools commonly employed in GMP and 21 CFR Part 11 laboratories.* These include secure user access, audit trails, digital signatures, data security and secure reporting.
Photo Diode Array Spectrometers
The system uses a bank of Zeiss UV spectrometers interfaced to the dip probes for optical sampling; no material is removed from the bath. 
This allows very rapid acquisition of a full UV spectrum from 200 nm to 720 nm, in steps of 2 nm, from all vessels. In the case of a controlled-release formulation, a typical system configuration might sample every 20 minutes for 24 hours. For an immediate-release formulation, samples may be taken as frequent as every second. Watch the compound dissolve in real time.
The precision of the Rainbow exhibits excellent analytical performance in the range of 0.001 to 2.0+ absorbance units. The low thermal expansion properties of the titanium body virtually eliminate drift due to ambient temperature fluctuations. The patented design of the MMS-UV spectrometer eliminates moving parts and ensures high wavelength accuracy and precision (observed annual drift of less than 0.1 nm).
Easy to Use Interface
Rainbow’s software interface, Indigo™ is simple and intuitive to navigate because it uses one screen interface to handle all tasks. Simply clicking tabs on the Indigo desktop takes the user from activity to activity with full access to every step at any time. Setting up a dissolution experiment or any spectral measurement is straightforward.
GMP and QC Environments
IndigoSAM™ software offers a full suite of security tools for the GMP and QC environments.* These include digital signatures, data audit trails and more. IndigoSAM, a secure account manager, provides Indigo users with a full suite of security tools commonly used in GMP and QC laboratories. Methods developed in Indigo may be imported into, locked down, and run in your secure environment.
* GMP and 21 CFR 11 compliance in any given IT environment is solely the responsibility of the user.
Dissolution Baths
