Wavelength Tech Forum: UV-vis Spectroscopy

This month’s Technology Forum looks at the topic of UV-vis spectroscopy and the trends and issues surrounding it. Joining us for this discussion are Alan Marks, with Thermo Fisher Scientific, Luis Moreno, with Hitachi High Technologies America, and Rob Morris, with Ocean Optics.

Is UV-vis in danger of being phased out?

(Marks) I do not anticipate that UV-Visible spectroscopy will be phased out in the foreseeable future. The simplicity and convenience of performing UV-Visible measurements is very hard to match compared to other techniques. The nondestructive nature of UV-Vis also provides the flexibility for the sample material to be measured by complimentary techniques. With the increased pressure on companies for monitoring and disposing of solvent waste materials and compounds, UV-Vis remains a technique of choice for measuring small volumes of liquids and solids. Measurements of liquids down to less than 1µl and solids down to 1-3 mm are available with the appropriate spectrophotometer and/or accessory system. At these levels waste disposal does not fall under the same guidelines as larger volumes of materials.

One of the important aspects of this technology is the ability to measure the appearance of materials. Appearance or color of materials we take for granted in our everyday lives is performed by visible instruments performing color analysis. Pharmaceutical companies patent specific colors which are used on products and packaging. These are monitored and regulated using visible reflectance spectroscopy.

One of the rapidly growing areas worldwide is the area of UV protection. With the continued increase in occurrence of skin cancer and cataracts, the requirement to regulate materials such as sunglasses, textiles and fabrics, sunscreen lotions, and SPF-labeled cosmetics is growing rapidly. All of these materials are characterized by UV spectroscopy with systems that can analyze the UVA and UVB spectral regions.

UV-Vis is a significant complementary technique to fluorescence. Using a UV-Vis instrument for initial screenings and determination of fluorescence excitation wavelengths is commonplace. As the fluorescence spectrofluorometer market and fluorescence imaging markets grow, so will the requirement for wavelength scanning UV-Vis instrumentation.

(Moreno) No. There is no question UV-Vis spectroscopy is a mature analytical technique, but it is still being used in multiple applications. This is a $700M market that has potential for modest growth.

(Morris) I don’t see such a thing happening any time soon, although UV-Vis spectroscopy has always represented a fairly modest piece of the spectroscopy pie. UV-Vis spectroscopy has lasted for decades, and is still one of the most affordable, accessible, and flexible of the spectroscopy technologies available. The gap in price and flexibility will continue to narrow between UV-Vis and other “scientific-grade” spectroscopy techniques like NIR and FT-IR, but UV-Vis will carry on.

How will multimodal spectroscopy change the landscape of the UV-vis industry?

(Marks) Multimodal spectroscopy (MMS) is one of the new developments in UV-Visible spectroscopy in recent years. There is no question this technology has the potential to make an impact on the traditional UV-Visible scanning market and other areas that use diode-array and simple CCD detection technologies. The cost of ownership compared to traditional techniques versus the overall performance of the system will play an important factor for customers switching to this technology. Also, the compatibility with various accessories providing flexibility for sample handling will also influence acceptance.

(Moreno) Multimodal spectroscopy will renew interest in UV-Vis with new applications and instrumentation designs.

(Morris) That’s difficult to say, because it’s still relatively new and expensive. There are always competing technologies that will come along an occupy a niche among the early adopters, but they are likely to achieve mass acceptance only until they become at least as inexpensive, flexible, and easy to use as the technology they hope to replace.

What role will UV-vis play in the future of protein research?

(Marks) UV-Vis instrumentation will continue to play a significant role in the foreseeable future for protein research. There are no other techniques that will replace the protein concentration estimation at 280 nm. Gels have the ability to be used, but the technique is much less quantitative than UV-Vis absorption measurements. As the cost of making complex proteins and peptides continues to grow, the trend toward high-quality measurements with lower and lower sample volumes will increase. Monitoring protein kinetics using UV-Vis is also a measurement technique that will continue well into the future. There are no other substitution techniques.

(Moreno) Until there is a routine, affordable technique to replace UV-Vis applications, it should continue as a technique of interest for the quantification of proteins.

(Morris) I really can’t answer this one. One of our founding fathers did some work with our spectrometers involving protein research, but the real art was not in the spectrometer, it was in the algorithm he developed for particle-size analysis.

Do you believe that UV-vis has a future in bioanalysis?

(Marks) UV-Vis continues to be the most cost-effective technique in the bioanalysis laboratory. There are currently no methodologies that exist which will replace UV-Vis from the bioanalysis laboratory. More importantly, given the trend of the pharmaceutical market toward larger molecule therapeutics, UV-Vis is well positioned to investigate the binding of peptide and protein drugs. UV-Vis is a fundamental technique that still has possible extensions in the bioanalysis market as researchers are always looking to get the highest quality data from the least amount of sample.

(Moreno) Definitely yes, it offers an economic way to analyze samples.

(Morris) Absolutely. There are many applications involving fluorescence, bioluminescence, and the like that involve samples with spectral response in the UV-Vis. One of our most successful OEM partners, for example, uses our UV-Vis systems for a DNA analysis application.

What do you see in the future for the UV-vis market?

(Marks) The acceptable cost of ownership will continue to shift downward due to market pressure. Many manufacturers are looking toward low cost regions to reduce the cost of components; this is already resulting in lower-cost instruments. There are already many low-cost UV-Visible instruments manufactured in China that are not currently exported. The market for UV-Visible instruments in China is approximately half the total USA market.

Monitoring the UV and Visible spectral regions will never go away, but the nature of the instruments and the product mix may vary. With continued advances in process control equipment and fiber optics, the technique for monitoring UV or Visible wavelengths close to the process or production line will continue to grow. In some areas, such as drug discovery, the requirement to measure more and more samples will continue to change the mix from traditional UV-Visible instruments to multichannel instruments, such as microplate readers. The requirement to analyze the appearance and color of materials using visible reflectance spectroscopy will never go away. Dedicated color-visible spectrophotometers will always have a place in the scientific arena and public domain.

(Moreno) It will continue to experience modest growth, with the tendency of prices to decrease as more Asian manufacturers enter the global market with high quality instrumentation. Software capabilities and accessory offerings will define the market and determine the leaders.

(Morris) If I knew I wouldn’t tell you, because then all my competitors would know, too!

What do you think?

Click here to participate in our "Question of the Month" survey on UV-vis Spectroscopy.