International Diffuse Reflectance Conference

In our original column on this topic [1] we had only done a principal component analysis to compare with the MLR results. One of the comments made, and it was made by all the responders, was to ask why we did not also do a PLS analysis of the synthetic linearity data. There were a number of reasons, and we offered to send the data to any or all of the responders who would care to do the PLS analysis and report the results. Of the original responders, Paul Chabot took us up on our offer. In addition, at the 1998 International Diffuse Reflectance Conference (The Chambersburg meeting), Susan Foulk also offered to do the PLS analysis of this data. 

A number of instrument suppliers as well as engineering specialty houses are able to install in-line NIR hardware in production settings. For up-to-date listings and manufacturers, a newcomer (or even experienced user) should scan the Internet, attend meetings such as PittCon, IFPAC, and more specialized conferences such as the International Diffuse Reflectance Conference... 

Figure 1 presents what may be referred to as the near-infrared method validation pyramid. Ritchie [11] presented this idea at the Ninth International Diffuse Reflectance Conference (Chambersburg) in 1998. Since then, he has presented it at the Spectroscopy in Process and Quality Control Conference (SPQ) in 1999, the Eastern Analytical Symposium (EAS) in 1999, and the Pittsburgh Conference and Exposition on Analytical Chemistry and Applied Spectroscopy (PittCon) in 2000. 

Esbensen, K (2002) Multivariate data analysis - in practice. CAMO Process AS, Oslo. Ritchie G (2002) Software shootout data. International Diffuse Reflection Conference, Cham-bersburg. 

G. E. Ritchie, Qualitative Uses of NIRA in Pharmaceutical Analysis, presented at 9th International Diffuse Reflectance Conference, Wilson College, Chambersburg, PA, August 1998. 

G. J. Kemeny and D. L. Wetzel, Acousto-Optic Tunable Filter Based Analyzer System, Third International Diffuse Reflectance Conference, August 17-22, 1986, Chambersburg, PA. 

G J. Kemeny, Proposed Standardization of Near-Infrared Blend Monitoring, International Diffuse Reflectance Conference, Chambersburg, 2004. 

After nearly 40 years as an internationally recognized authority in this field, Karl was awarded a well-deserved honorary doctorate by Wilson College on August 10, 2006. This came as a surprise during the 25th anniversary celebration of the International Diffuse Reflectance Conference in Chambersburg, PA, before a crowd of nearly 150 colleagues. 

Hoult, R.A. Spragg, R.A. Abrasive sampling for diffuse reflectance using reflective substrates, Fourier Transform Spectroscopy, 12th International Conference Itoh, K., Tasumi, M., Eds. Waseda University Press Tokyo, 1999, 506-507. 

Two book chapters discussing NIR analysis of tablets were published in 1991. The first was from the Fourth International Conference on NIRS [92], In it, Stark used a newly developed diode array spectrometer scanning from 520 to 1800 nm. The instrument was useful for macro- and microspecimens. Samples were placed on a glass slide maintained at an angle to the probe. Spectra were collected from a 1-mg sample of acetaminophen powder. The sample was divided into 500, 250, and 125 mg. Diffuse reflectance spectra of intact acetaminophen, ibuprofen, and antacid tablets were collected. 

B. Barabas. Comparison of measurability of two produces of high protein content. In Near Infrared diffuse reflectance/transmittance spectroscopy. Proceedings of the International NIR/NFF conference, Budapest, Hungary, May 12-16,1986. J. Hollo, et al co-eds. Akademiai Kiado, Budapest. 1987, p. 169-176. 

Guiader, M., Cheese and meat analysis by NIR, International Near Infrared Diffuse Reflectance/Transmittance Spectroscopy Conference, Budapest, Hungary, May 1986. 

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