Just a couple weeks ago, I had an opportunity to visit Natoli Engineering at St. Louis; MO. Dale Natoli introduced me to Mike Ponstingl of Custom Sensors and Technology’s (CST). Natoli Engineering has been working closely with CST for Light induced fluorescence (LIF) applications. GlaxoSmithKline (GSK) and CST have co-developed LIF’s pharma application, a technology used for a number of years in several other process industries.

LIF offers a novel solution to a number of applications to the pharma community. CST has developed a multi-wavelength capable LIF Sensor with part-per-billion level detection limits. Initially designed for “blend drug content uniformity” and “real-time end point detection” during the blending of powders, the sensor’s high sensitivity is ideal for cleaning validation measurements.

The sensor may measure surfaces directly for cleanliness, eliminating lab time and HPLC analysis, or it may be used to measure liquid rinse samples. In addition, fluorescence can also be used in the measurement of pharmaceutical waters for effluent monitoring. The sensor can be utilized across a wide variety of application scenarios through in-line, on-line or at-line deployment. In order to address multiple applications, the sensor can be reconfigured by simply swapping out the probe sleeve, offering versatility and ease in obtaining multi-wavelength data.

The LIF Sensor was designed as a Process Analytical Technology (PAT) Tool with a strong emphasis on smart-sensing. Real-time detection assurance is provided by the health and diagnostics information. The source LEDs provide integrated referencing on each diode for monitoring and referencing capabilities. Additional features of the LIF Sensor include:

1. Dynamic control to provide tailored analytical versatility via UV-Vis LED array technologies
2. Small, lightweight, self-contained form factor for the “sensor” device
3. Communication options including WiFi or Ethernet with OPC, Modus, and 4-20 platforms
4. Multiple powering options, both AC and battery
5. Optical configurations suitable for various sample phases (liquid, solid, gas)
6. Onboard accelerometer for mobile applications such as pharmaceutical final drug product tumble and bin blending

The dynamic control of the detector, source LEDs and the swappable probes that provide for multi-wavelength analysis; allow for one sensor to be applied for multiple applications. As a valuable new piece of PAT, the LIF sensor enables manufacturers to build quality into the process, utilizing QbD to the fullest extent. Along with quality comes a decrease in product waste, reduced labor, and less equipment needed, making the LIF an economically attractive solution for all fluorescence applications. Software features include 21 CFR Part 11 compliance, system administration and user access levels, method and calibration management, various analysis modes, data integrity, audit control, and electronic signatures that collectively provide the security and compliance required by the pharmaceutical industry. These comprehensive sensor novelties afford reliable monitoring for robust process control.

Sensors can be applied to several realtime analytical problems such as end-point detection for powder blending, cleaning validation, security/surveillance, color measurement, protein purity and other applications in biologics for cleaning validation!

I am very confident that the LIF technology is going to catch on quickly within pharma due to its wide variety of applications for precision cleaning validation, which offers tremendous time and cost savings!

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Makarand (Mak) Jawadekar most recently served as Director, Portfolio Management and Performance at Pfizer Global R&D, until February 2010, when he opted for an early retirement after 28 years at Pfizer Inc. He currently serves on several companies’ advisory boards and also consults with bio/pharmaceutical companies for global outreach in emerging market regions. He can be reached at mjawadekar@yahoo.com.