18 chromatography • spectroscopy
Figs, 2, 3, and 4. (Paracetamol Raman Spectra, Carbamazepine Raman Spectra and Alpha Lactose Raman Spectra) The results of the Raman measurements of the four samples are illustrated in these following graphs.
study characteristics of active ingredients, binders, fillers, lubricants and excipients.
Fig. 2.
Raman techniques can be used to acquire data through vial walls, pill pack windows and bags - packaging forms that are frequently used in the biomedical and pharmaceutical industries. A typical application for the pharmaceutical market is the capability of discerning pharmaceutical raw materials such as active ingredients, binders, fillers, lubricants and other excipients commonly used by this industry. Today, portable Raman instruments allow authorities to detect counterfeited pharmaceuticals and contaminated raw materials. To illustrate the capabilities of Raman spectroscopy Ocean Optics has analysed the following pharmaceutical active ingredients (Paracetamol and Carbamazepine) as well as two commonly used excipients (alpha and beta Lactose).
Fig. 3.
Te samples studied consisted of simple organic compounds including excipients and active pharmaceutical ingredients. Tey were contained in standard, clear borosilicate scintillation vials with no additional preparation applied. Most samples were purchased or obtained from a major pharmaceutical company.
Te samples were analysed using an Ocean Optics QE65000 Raman-configured spectrometer incorporating a back-thinned, cooled detector array. For the light source we used a 785nm laser specifically developed for Raman spectroscopy
References: Fig. 4.
system with a 785nm laser and one with a 532nm laser? Te 785nm version is designed to minimize the fluorescence signal, making it useful for chemical identification and fingerprinting. What’s more, the 785nm version generates well defined peaks for use
www.scientistlive.com
in chemometric analysis and can provide semi-quantitative data. For applications where C-OH structural information is important, the 532 nm version is your best option. Such measurements are typical of biological and pharmaceutical sample analysis, where researchers
1. R H Clarke, S Londhe, and M E Womble, “Low-resolution Raman Spectroscopy as an Analytical Tool for Organic Liquids”, Department of Chemistry and Photonics Center, Boston University, Boston
2. R H Clarke, S Londhe, W R Premasiri and M E Womble, “Low Resolution Raman Spectroscopy Instrumentation and Applications for Chemical Analysis”, Clarke Journal of Raman Spectroscopy, 1999, Vol 30: pp. 827-832.
3. J Macho, “Practical Mobile Raman Spectroscopy”, Raman Technology for Today’s Spectroscopists, Spectroscopy, June 2007
4. M Schmitt and J Popp, “Raman Spectroscopy at the Beginning of the 21st Century”, J Raman Spectroscopy, 2006 Vol 37: pp. 20-28
with 500mW output and a narrow spectral line width of only 0.2nm. Light was delivered to and collected from the sample using a fibre optic probe specifically designed to work at the laser wavelength with appropriate filtering to remove the Rayleigh laser line. In order to take the measurements the tip of the probe was placed at the bottom of the glass vials containing the samples. Te samples were measured using an integration time of 8 seconds and averaging three readings.
Te system picture illustrates the overall modular set-up, including the QE65000 spectrometer (black), the laser (white) and the fibre optic Raman probe.
Conlusion
Te spectra obtained in this study show the typical Raman features for these active and excipient substances. Tis demonstrates that such a modular approach to Raman instrumentation can be used to discern the main features of these pharmaceutical samples and differentiate the different raw materials based on their spectral fingerprint. Furthermore, with proper method development and chemometric techniques, this approach may help obtain semi-quantitative data of the active ingredient content in a pharmaceutical mixture.
Enter 18 or ✔ at
www.scientistlive.com/eurolab Nick Barnett – UK Country Manager
Ocean Optics BV, Duiven, The Netherlands.
www.oceanoptics.eu
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44