Near-infrared (NIR) chemical imaging is emerging as the analytical tool of choice for drug formulation development, analysis and process monitoring of the increasing number of advanced drug delivery systems.
>Spectral Dimensions, the leader in NIR chemical imaging systems, now receives 80 per cent of its business from the pharmaceutical market, part of which it attributes to an increase use of its products for advanced drug delivery systems.
The company now also provides NIR chemical imaging outsourcing services to at least half of the top 100 pharmaceutical companies, who are not yet ready to bring the required machinery in-house.
Drug companies are now doing more complex and exciting things with dosage forms, including controlled-release tablets, multi-coated tablets, granule coatings and transdermal patches, in order to survive in increasingly competitive markets.
A relatively emerging market, transdermal delivery is now worth $12.7 bn (€10.7 bn) and is expected to increase to $21.5 billion in the year 2010 and $31.5 bn in the year 2015.
In the past, the main emphasis of quality control in pharmaceuticals has been on the potency and purity of the ingredients in a blend. But this discounts other physical factors, caused by inadequate formulation or process control, such as the size and distribution of the ingredient particles that can also affect the performance of a drug.
As drug delivery systems are becoming more sophisticated, the complex components involved need to be checked more carefully during formulation development and quality control than traditional delivery systems.
Standard NIR spectroscopy can measure the constituents and average blending characteristics of a drug product. However, a chemical imaging system provides additional information - including the identities and relative arrangement and sizes of component particles, providing a more complete assessment of the mixture.
NIR chemical imaging works by taking a series of images across the known infrared spectrum of a drug sample. This chemical image represents the relative distribution of the active pharmaceutical ingredient (API) and excipients throughout the drug, and the accompanying software then turns the visual into a quantitative picture.