Re-Imagining
Raman Sampling Optics

RIO 100

Introduction

This year we started to see the benefits of the ongoing focus on invention and innovation to identify and develop new Raman products for Life Sciences and other industries that utilize Raman spectroscopy as an advanced analytical tool.

The RIO 100 is the first of the next generation of Raman probe optics incorporating the technical innovation disclosed in the granted patent “Raman Immersion Probe Systems and Methods”

The collimated laser and backscatter Raman collection design relates closely to Transmission Raman as both rely on diffuse scattering and photon migration within the sample to enhance the Raman signal and provide representative sampling while at the same time avoiding the unwanted Raman signal from surface coatings or the probe optic window.

Products

RIO 50 Plus

RIO 50 Plus2nd Quarter

Non-Contact probe optic using collimated laser and backscatter collection, Plus Real-Time Raman Calibration Unwanted wavenumber shifts observed in the Raman spectra due to laser wavelength and spectrograph drifting or instability can be identified and corrected for in real time.

RIO 100 - Raman Immersion Optic

RIO 100

With the retroreflector module it is an immersion optic that can collect Raman spectra from turbid liquids (Colloids, Suspensions, Slurries), without the retroreflector module it is a non-contact optic that can collect Raman spectra directly from solids. (Powders, Blends, Tablets)

RIO 200S Plus

RIO 200S Plus3rd Quarter

Immersion probe optic using focused laser and back scatter collection, Plus Real-Time Raman Calibration.By constructing the focusing lens from the calibration material fast f/2 data collection and Real-Time Raman Calibration are combined.

New Products

The technical innovation outlined within the following patent applications will be incorporated into a series of new products for release during this year.

"Solids Analysis using Raman Spectroscopy" Collimated laser and backscatter collection from solids is an alternative to transmission Raman. The addition of the Raman optical module to a research Raman microscope will enable quantitative measurements from solid samples while avoiding unwanted Raman signals from surface coatings.

"Real-Time Raman Calibration" is a technique to significantly improve the spectral precision of Raman instruments using an encoding immersion probe optic. Improving spectral precision and reproducibility between probes and instruments will be very beneficial for developing improved chemical models and calibration transfer.

RIO 100 with Retroreflector

Description - RIO 100 with Retroreflector

The RIO 100 with the retroreflector is an immersion optic that can collect Raman spectra from turbid liquids.

  • The collimated laser and backscatter Raman collection design relates closely to Transmission Raman as both rely on diffuse scattering and photon migration within the sample to enhance the Raman signal and provide Representative Sampling while at the same time significantly reducing the unwanted Raman signal from the probe optic window.
  • The RIO 100 Raman Immersion optic offers an adjustable optical pathlength (0 to 40mm) with signal enhancing retroreflector.
  • This probe optic is a retrofit option for use with most Raman instruments.

Applications - Turbid Liquids - Colloids, Suspensions, and Slurries

  • Nucleation, crystallization, upstream and downstream fermentation processes, nanoparticles, and micro-plastics are potential applications that will benefit from using this Raman Immersion Optic.

RIO 100 - Raman Non-Contact Optic

RIO 100 without Retroreflector

Description - RIO 100 without Retroreflector

The RIO 100 without the retroreflector acts a non-contact optic that can collect Raman spectra directly from solids.

  • The collimated laser and backscatter Raman collection design relates closely to Transmission Raman as both rely on diffuse scattering and photon migration within the sample to enhance the Raman signal and provide representative sampling while at the same time avoiding the unwanted Raman signal from surface coatings.
  • The RIO 100 Raman Non-Contact optic offers an extended working distance and depth of field.
  • This probe optic is a retrofit option for use with most Raman instruments.

Applications - Solids, Powders, Blends, Granules

  • Qualitative and Quantitative measurements on tablets, capsules, packaged pharma products are applications that will benefit from using this Raman Non-Contact Optic.

Benefits - RIO 100 Non-Contact Configuration

Raman spectra collected from an over-the-counter Excedrin tablet using a research Raman microscope with a focusing 20X objective. The surface coating generates a strong unwanted signal

Figure 1

Raman spectra collected from the over-the-counter Excedrin tablet using a 5mm spot collimated laser and backscatter collection, Enabling representative sampling with the surface coating not an issue.

Figure 1

Features

  • Diffuse scattering: Particles within the sampling volume will enhance the Raman signal by diffuse scattering and photon migration effectively increasing the laser pathlength as it is scattered internally within the sample.
  • Signal Enhancement: A collimated laser input beam and a Laser/Raman retroreflector increases the Raman signal by up to a factor of 4.
  • Representative Sampling: By using a large diameter collimated laser input and backscatter collection representative sampling enables improved qualitative and quantitative measurements.
  • Calibration Transfer: More reproducible Raman spectra offer the opportunity to create globally transferable chemometric prediction models.
  • Sampling Pathlength: The adjustable sampling pathlength allows you to set up the optimum Raman collection conditions for samples containing particles, potentially making it well suited for looking at small and sub-micron particles.
  • Reduced Window Fouling: Reduced potential for laser induced fouling at the surface of the window due to eliminating localized high laser energy densities at the window.
  • Achromatic Design: Eliminates chromatic blur within the sample avoiding the spectral distortion generated over the extended Raman wavenumber range as experienced by single lens-based probe optics.

Specifications

Laser Wavelength
785nm
Probe Length
250mm
Probe Diameter
1⁄2”
Probe Material
316L SS
Probe Finish
Electrolytic Polish
Window Material
C-axis Sapphire
Window Seal
Epoxy Cement
Sample Pathlength
0 to 20mm
Optical Pathlength
0 to 40mm
Reflector Module
750nm to 1100nm
Operating Temperature
-20°C to 150°C

References

Granted Patent – US 10,976,259 B2
Raman Immersion Probe Systems and Methods

Application Notes

"Solids Analysis using Raman Spectroscopy"

Collimated laser and backscatter collection from solids is an alternative to transmission Raman. A simple upgrade to a research Raman microscope will enable quantitative measurements from solid samples while avoiding unwanted Raman signals from surface coatings.

The Raman collimated laser and backscatter collection as per the schematic below takes advantage of diffuse scattering and photon migration within the sample to enhance the Raman signal as outlined in the following figures for Raman spectral plots from a pharmaceutical tablet.

Using the RIO 100 Raman Immersion Optic we will also see the Raman enhancement effect in turbid liquids containing colloids or larger particles benefiting from increased laser power and the addition of a retro-reflector.

Probehead

Figure 1

Figure 1 Raman spectra collected using a research Raman microscope from an over-the-counter Excedrin tablet using a large spot (5mm) collimated laser and backscatter collection, with low laser power and no reflector in place.

Figure 2

Figure 2 The Raman spectra collected from an over-the-counter Excedrin tablet using a research Raman microscope with a focusing 20X objective. The surface coating generates a strong unwanted signal while the Raman spectra in Figure 1 uses a collimated laser that effectively passes through the surface coating and the Raman spectra from the bulk of the sample dominates the combined Raman spectra as per Transmission Raman.

Figure 3

Figure 3 Superimposed Raman spectra from Figure 1 (in red) and the Raman spectra from the shaved, coating free Excedrin tablet using a research Raman microscope with a focusing 20X objective (in blue). The Excedrin tablet contains 3 components and the additional Raman bands present within the Raman spectra from Figure 1 indicate that more representative bulk sampling of the tablet by using the collimated laser and backscatter collection was achieved.

Summary

This simple experiment demonstrates that Collimated laser and backscattered collection from a coated pharmaceutical tablet has the potential to be an alternative quantitative measurement tool to transmission Raman.

References

  1. Matousek, P., Parker,A.W., “Bulk Raman Analysis of Pharmaceutical Tablets”, Applied Spectroscopy 2006, Volume 60
  2. Anders Sparén, Jonas Johansson, Olof Svensson, Staffan Folestad, & Mike Claybourne, “Transmission Raman Spectroscopy for Quantitative Analysis of Pharmaceutical Solids” American Pharmaceutical Review, January 2009
  3. Neil Everall, Pavel Matousek, Neil MacLeod, Kate L. Ronayne, & Ian P. Clark,” Temporal and Spatial Resolution in Transmission Raman Spectroscopy", Applied Spectroscopy 2010, Volume 64

Biography

Harry Owen a recognized expert in the field of Raman spectroscopy is now director of his own company focusing on pursuing his passion for invention and innovation by creating and patenting new Raman products and applications for existing and new markets.

He was Born in Manchester, UK, is married to Susan has 3 sons and is currently residing in Michigan, USA.

Education

MSc. Solid State Physics, University of London
Grad. Inst. Physics, John Dalton College of Technology

Experience

As Vice President and Director of Business Development at Kaiser Optical Systems he founded a successful new business utilizing Raman spectroscopy to develop a range of innovative spectroscopic components and instruments.

Awards

“Recognized as a pioneer in the Development of Scientific Instrumentation: Raman Spectroscopy” at the Fourteenth James L Waters Annual Symposium at the 2003 Pittsburgh Conference.

James L. Waters Award

Top Left: M. Bonner Denton, Charles W. Gardner, Bruce Chase, Harry Owen.
Bottom Left: James L Waters, Fran Adar.

The Williams-Wright Award from the Coblentz Society at the 2006 Pittsburgh Conference for the development of novel holographic optical components designed to enable the development of a new generation of compact and robust Raman instruments.

Williams Wright Award

Left: Don Pivonka, Harry Owen, Bob Messerschmidt

HORC Raman Patent Portfolio

Granted Patent - U.S. 10,746,596 B2
Probe Optic Light Shields

Granted Patent – US 10,976,259 B2
Raman Immersion Probe Systems and Methods

Published Patent – US 2020/0257110 A1
Improved Raman Immersion Probe Optics

Provisional Patent – Serial No. 63/058,714
Real Time Raman Calibration

Provisional Patent – Serial No. 63/122,261
Solids Analysis using Raman Spectroscopy

Granted Patents

A track record for invention across 4 different scientific fields is supported by the award of 13 US patents and 3 pending patents from 1978 to 2021.

Raman Applications

US Patent 10,139,329
Particle Size Determination using Raman Spectroscopy

US Patent 6,867,858
Raman spectroscopy crystallization analysis method

Raman Instrumentation

US Patent 5,377,004
Remote optical measurement probe.

US Patent 5,011,284
Detection system for Raman scattering employing holographic diffraction

US Patent 8,675,190
Large-collection-area Raman probe with reduced background fluorescence

US Patent 7,148,963
Large-collection-area optical probe

Holographic Optical Elements

US Patent 5,559,597
Spectrograph with multiplexing of different wavelength regions onto a single opto-electric detector array

US Patent 5,530,565
Holographic transmission bandpass filter.

Photochromic Glasses

US Patent 4,349,634
Method of preparing photochromic glass.

US Patent 4,290,813
Photochromic boro-silicate glass.

US Patent 4,102,693
Photochromic boro-silicate glass.

Contact

Primary

All countries not covered by exclusive partners.

Full name
Harry Owen
Company
HORC
Email address
harry@horc.us
Telephone
+1 248-933-6935
Address
Michigan, USA
About
A recognized expert in the field of Raman spectroscopy focused on creating the Next Generation of Raman Immersion Probe Optics to improve existing and develop new applications and market opportunities.

Exclusive Partner

for Japan

Full name
Dr. Hiroshi Hisada
Company
Tekanalysis Inc.
Email address
hisada@tekanalysis.jp
Telephone
+81 90 4037 2065
Address
Osaka, Japan
About
Hiroshi Hisada founded Tekanalysis, a company that sells and supports Raman analyzers that can be used for drug analysis and research using vibration spectroscopy. He graduated from Meiji Pharmaceutical University Graduate School and obtained his doctorate (Pharmacy and Health Sciences).

Exclusive Partner

for all of Ireland

Full name
Donnchadha Quilty
Company
Particular Sciences Ltd.
Email address
hdonq@particular.ie
Address
Dublin, Ireland
About
Particular Sciences have worked with lab and at-line Raman systems for several years. Particular Sciences specialize in the material characterization of chemicals. They have a 31-year track record in Ireland with world-leading instrument suppliers offering full suites of support to Pharma, BioPharma, Medical Devices, NanoTechnology and specialty materials companies.

Exclusive Partner

for Korea

Full name
Kon-Pyo, Hong
Company
Sunil-Ina Instrument Co., Ltd.
Email address
sunilina@sunilina.com
Address
5, Dongwon-ro 21Beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do, 13547 Korea