News

Posted On: 02/27/2006

Less is More: Spectroscopy for a New Generation

PharmaManufacturing.com

By Agnes Shanley, Editor in Chief

Of the new and improved analytical technologies presented at the 2006 International Forum for Process Analysis and Control (IFPAC) in Arlington, Va., two were real standouts, promising to make spectroscopy easier, faster, and far less expensive for pharmaceutical quality control operations than it is today.

SpectrinLine processware, introduced by Ometric, a new company established a year ago in Charleston, S.C., combines optical spectroscopy with multivariate optical computing (MVOC). MVOC is a technology that Michael Myrick, a chemistry professor at the University of South Carolina has been perfecting for the past 10 years. It can be used with any form of optical spectroscopy.

“MVOC takes the power of spectroscopy and speeds it up,” explains Chief Technology Officer, Robert Freese, “so that analysis can be done in real time, in-line.” Dr. Freese, who founded the optical storage firm Alphatronix, was a member of the 3M Corp. team that invented the erasable optical computer disc in the late 1980s.

MVOC can be used in pharmaceutical applications, but also in environmental, chemical and food analysis, and has received funding from the U.S. Department of Defense, for use in the detection of airborne nerve gases.

With MVOC, computer algorithms are developed based on the pattern of a specific measurement (whether for a specific compound or impurity, or a variable that is critical to product quality). Other algorithms are then used to design an optical filter that will recognize that pattern. Different filters can be developed at low cost, for different variables or materials, customized for each specific installation.

Instead of buying the technology outright, pharmaceutical customers would license SpectrInline for each specific application. They would send Ometric spectra for one specific production line or operation, so that filters could be customized to detect the most critical contaminants or to monitor the most important process variables.

No product samples ever need be exchanged — only spectra. This practice eliminates the need for capital investment, and enhances the security of the licensee’s process technology.

SpectrinLine has already been tested for pharmaceutical tableting applications, where it has reportedly achieved real-time in-line testing at the rate of five tablets per second. For a process line producing 100,000 tablets per hour, for example, six systems could be used to perform 100% final product testing. The system could also be used upstream, to monitor blending or drying in real time.

Spectrinline is expected to help the drug industry minimize product recalls, reduce the time and resources now wasted by product sampling and QC laboratory testing, and improve operator safety, said CEO Walter Alessandrini, a fiber optics entrepreneur from Genoa, Italy, who previously led the fiber optic equipment firm, Avanex. Ometric was formerly known as Opton Technologies.

Also notable were Polychromix’s (Wilmington, Mass.) Near Infrared Digital Transform Spectrometers (DTS). The devices, first developed by Sandia National Laboratories, and later improved by Honeywell and an MIT team led by Stephen Senturia (now CTO of the company), use micro-electromechanical systems (MEMS) in a portable form factor, featuring a single InGaAs detector and no moving parts.

A sample spectrum is dispersed across the MEMS chip, and applying voltage to individual pixels within the chip determines which pixels diffract, and which reflect light. A fixed grating, rather than an expensive detector array, then collects and recombines reflected light onto a photodetector. As a result, the device costs significantly less than traditional spectrometers that use detector arrays. The devices cost less than $10,000, with some models selling for $5,000 to $7,500.

The spectrometers can be operated in a number of modes, including:

• Monochromator, in which the MEMS chip selects one spectral region at a time, diffracting all other wavelengths. Scanning each pixel across the chip then produces the full spectrum.



• NDIR, in which a sequence of filters is created within the MEMS that functions like a filter wheel.



• Chemometric, in which analog control is used for each pixel, and multiple wavelengths are analyzed using “optimum partial least squares” weighting, so that output is proportional to the concentration of target compound.

The devices are small (in the neighborhood of 3 x 4 x 5 in), light and energy efficient and use a standard USB connection for both communications and power connections.

Both Ometric's and Polychromix's technologies will be demonstrated in March, at the Pittcon conference in Orlando, Fla.