Application of a Fiber Optic Refractometric Sensor to Measure the Concentration of Paracetamol in Crystallization Experiments
- Resource Type
- Authors
- Patrícia Cruz; Susana Novais; Liliana Soares; Susana Silva; Orlando Frezao; António Ferreira
- Source
- IEEE Instrumentation & Measurement Magazine. 24:36-40
- Subject
- Optical fiber
Materials science
Multi-mode optical fiber
Single-mode optical fiber
Analytical chemistry
Physics::Optics
Model system
Measure (mathematics)
law.invention
law
Electrical and Electronic Engineering
Crystallization
A fibers
Instrumentation
Oscillatory flow
- Language
- ISSN
- 1941-0123
1094-6969
A refractometric sensor was applied to measure in real-time the concentration of Active Pharmaceutical Ingredients (APIs) in crystallization experiments. Paracetamol was used as a model system due to the extensive literature available for this API. The refractometric sensor was fabricated by a simple and inexpensive method that consisted in splicing a short section of a multimode fiber to a single mode fiber. The compact geometry of this sensor, with an external diameter of just $125\ \mu\mathrm{m}$ , allowed it to measure the concentration of paracetamol, both in a stirred tank crystallizer operating in batch and in an oscillatory flow crystallizer operating continuously. The proposed technique shows the potential to monitor the concentration of APIs in crystallizers of different sizes and geometries as an alternative to more expensive and complex analysis equipment.