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How Companies And Scientists Are Greening The Analytical Lab

Although green chemistry is a latecomer to the lab, instruments and analysis methods are changing

by Ann M. Thayer
November 30, 2015 | A version of this story appeared in Volume 93, Issue 47

Two researchers using Waters’s Acquity ultraperformance liquid chromatography system.
Credit: Waters Corp.
Waters’s Acquity UPLC system consumes less eluent than traditional HPLC.

Green chemistry principles have been seeping into the chemical community’s consciousness for at least 20 years, but they haven’t fully permeated all corners. One such corner is the analytical lab.

“In some respects, the analytical community has been slower to embrace green chemistry than the organic community,” says Douglas Raynie of South Dakota State University. An industrial scientist turned academic, Raynie teaches a green analytical chemistry course at the annual Pittsburgh Conference on Analytical Chemistry & Applied Spectroscopy, or Pittcon.

Scale is a reason. Organic chemists in industry have more opportunity to develop green processes when they scale up reactions, Raynie explains. In contrast, analytical chemistry is seen as a “necessary evil” for one-off purity checks or regulatory compliance tests. “Because they have to do it, people are more willing to tolerate certain inefficiencies,” he says.

But analytical lab volumes add up. Thus, instrument makers are making an effort to design equipment that is more energy efficient, uses fewer hazardous chemicals, and generates less waste. They are also designing their machines for environmentally friendly end-of-life disposal.

Credit: Thermo Fisher Scientific
Ion chips from gene-sequencing systems can be recycled to recover valuable metals.
Close-up of Ion semiconductor chip used in gene sequencing systems.
Credit: Thermo Fisher Scientific
Ion chips from gene-sequencing systems can be recycled to recover valuable metals.

In many other ways, though, the greening of the instrumentation industry comes not from a desire to do better for the environment but as a by-product of scientific progress. That’s good news for researchers, because few of them are willing to sacrifice speed or accuracy for a green seal of approval.

Indeed, despite numerous grassroots efforts among academic researchers, especially around greener sample extraction and analysis methods, customers don’t appear to be clamoring for green instrumentation. Only 3% of labs are required by their organizations to purchase green lab products, according to a 2014 survey conducted by K.C. Associates for C&EN Media Group.

About 11% of the 400 labs surveyed are encouraged to consider green alternatives as a first choice in buying lab products, and 21% are so encouraged if the cost and performance are equal. But this attitude applies foremost to office supplies, then to chemicals and solvents, and very much less to equipment and instruments.

“People won’t necessarily pay extra for greenness if all of the other attributes are the same,” Raynie says. “But if it is green and it is quicker, or green and more sensitive, then there is more of an impetus to buy.”

Who is doing the purchasing also comes into play. Progressive companies or younger employees who have grown up with more of an environmental mind-set are more likely to look for something green, Raynie adds.

In fact, the survey found, attitudes have been shifting over the past six years. About 55% of respondents expect that their organizations’ requirements to purchase green products will increase over five years.

Large companies looking to cut energy consumption as part of sustainability initiatives may not even look at their analytical instrumentation. “The lab is such a small component of their energy use,” says James McCabe, sustainability manager at the instrument maker Waters Corp.

But other savings can be found. For long-lived pieces of equipment, managing solvents, consumables, and hazardous wastes can have a significant impact on operating costs and returns on investments.

McCabe often conducts life-cycle analyses for customers. In one case, a customer asked him to compare the production, transportation, use, emissions, and end-of-life profiles of high-performance liquid chromatography (HPLC) and ultra-performance LC (UPLC), two of the company’s big areas of business.

The “use” step includes solvents, energy, glassware, and consumables. Solvents can factor in twice, McCabe explains. Not only is there the up-front cost to buy them, but they can also come with a high cost of disposal, especially if innocuous materials are mixed with hazardous ones.

Credit: Bruker Corp.
Bruker’s Ascend NMR magnets are actively shielded to reduce stray magnetic fields.
Operator at nuclear magnetic resonance console with Ascend superconducting magnet in background.
Credit: Bruker Corp.
Bruker’s Ascend NMR magnets are actively shielded to reduce stray magnetic fields.

Life-cycle analyses are part of Waters’s move toward “sustainable innovation” to address energy and materials use. Other instrument makers have similar initiatives. PerkinElmer’s Eco-Innovative Products and Mettler Toledo’s EcoDesign programs try to minimize health and environmental impacts. Thermo Fisher Scientific calls its program “re:” and highlights greener products with a leaf symbol.

Such programs often look beyond solvents and other consumables to the instruments themselves because suppliers increasingly must meet international regulations around materials use and disposal.

Under the European Union’s Waste Electrical & Electronic Equipment Directive, firms must supply information for the disassembly and recycling of equipment. Companies also will have to be compliant with the EU’s Restriction of Hazardous Substances Directive, which restricts some heavy metals and other substances, by 2017.

Most suppliers have take-back programs for recycling, trade-in, or trade-up of their instruments. The business is “moving on to an economy of ‘cradle to cradle,’ ” according to Cristina Amorim, chief sustainability officer for Thermo Fisher’s life sciences group. “We no longer look at designing for manufacturability; we now look at designing for disassembly because we know that we are going to have to bring it back and take it apart.”

Speaking at the Inform­Ex trade show earlier this year, Amorim described how refurbishing old machines saved Thermo Fisher $100,000 and diverted 18 metric tons of waste from landfills. Harvesting high-value parts generated another $200,000. And recycling gene-sequencer chips returned by customers brought in $45,000.

“We are not losing any money in that endeavor,” she said about reclaiming metal from the chips. “Green chemistry and engineering are paying off.”

One of the principles of green chemistry is safer chemistry. The instrument maker Bruker addressed operator safety and working conditions by developing technology to reduce stray magnet fields emanating from nuclear magnetic resonance (NMR), magnetic resonance imaging (MRI), and Fourier transform mass spectrometer (FTMS) systems.

Stray fields can attract metal objects, erase information on magnetic media, and damage electronics. Even more critical, exposure to variations in field strength may affect medical devices such as pacemakers.

An unshielded high-field magnet can have a stray field as high as 5 gauss extending 4 to 5 meters. By actively shielding the main magnet coil, Bruker has reduced the stray field to not much more than Earth’s field, the firm says. This change, combined with reduced sizes and weights, means that magnets can be housed in smaller rooms and don’t require physical shielding or other support structures.

Such efforts notwithstanding, green chemistry is not necessarily one of the design criteria when suppliers create new instruments, Raynie suggests. Instead, technology developments, such as the move toward smaller diameter chromatography columns, often yield unintentional gains in greenness. “Either way, they are putting green chemistry thinking out into the perception of the end user,” he says.

Applying Green Chemistry

Several of the discipline’s defining principles can be adapted for analytical methods.

SOURCES: Chem. Rev. 2007, DOI: 10.1021/cr068359e; Pure Appl. Chem. 2013, DOI: 10.1351/pac-con-13-02-05; and Trends Anal. Chem. 2013, DOI: 10.1016/j.trac.2013.04.010

A distinction made by Daryl Belock, vice president for innovation and R&D collaboration in Thermo Fisher’s analytical instruments unit, is telling. Avoiding hazardous materials or chemistries and reducing energy use are part of product development discussions at the firm, Belock explains. But more important, he says, product design requires “ruthless prioritization on the aspects that create the most value for the customer.”

Innovation and productivity are two primary design considerations, Belock says. Researchers don’t want to sacrifice performance and, in fact, hope to see innovations in accuracy, precision, sensitivity, and other features when purchasing new equipment. On the productivity side, users typically want quality, robustness, throughput, and reduced cost of ownership.

The truth of the matter is that, for instrumentation firms, environmental impact is typically not the main criterion in new product development. They know users aren’t willing to make trade-offs, such as adding 10% to run time or giving up 0.5 ppm in accuracy to use 10% less power.

However, often they don’t have to. For example, Thermo Fisher developed a new fluorescence imaging microscope in which it replaced mercury lamps with more stable and longer-lived light-emitting diodes. Similarly, the company has redesigned some of its polymerase chain reaction (PCR) instruments to be smaller, lighter, and more energy efficient and to use less material in ­construction.

In the case of instrument size, a smaller instrument footprint just makes good business sense. “Customers want everything at their disposal, and companies like us are constantly competing for their bench space,” Amorim pointed out. “Prime space in the lab is quite important, and the smaller the footprint, the more we actually get of it.”

Helping customers conserve resources is also a good business move. A few years ago, customers began struggling with rising helium costs and shortages. For its gas chromatographs, Thermo Fisher created a helium-saving module that reduces the amount of gas needed in sample injection and transport.

Meanwhile, liquefied helium use in cooling superconducting magnets became significant at Bruker, which has made other design changes in addition to shielding magnets for NMR, MRI, and FT-MS systems.

An added refrigeration unit eliminates the need for liquid nitrogen cooling, while helium reliquefaction reduces consumption of the gas to “near zero,” explains Thorsten Thiel, head of marketing communications. Getting rid of the nitrogen-containing vessel also reduces the magnet size and weight.

The change was driven in large part by MRI users in clinical settings, such as hospitals, who don’t want to handle the cryogens and routinely refill the magnets, Thiel says. Bruker has been able to adapt the technology so that it also works on the high-field magnets of up to 1 gigahertz that are used in research settings. Doing so required “balancing performance versus convenience versus sustainability,” he adds.

Measuring Success: Analytical chemists are attempting to develop green metrics

Although much effort in chromatography is directed at reducing solvent use, the field has lacked metrics to determine the relative greenness of methods and evaluate the specific solvents used. Analytical chemists are borrowing from work done by organic and medicinal chemists, including solvent selection guides created by green chemistry groups and pharmaceutical companies.

Several metrics have emerged within the analytical chemistry field to create standard measures by which to gauge progress. An environmental assessment tool called HPLC-EAT that came largely out of Lund University and another from Merck & Co. researchers dubbed Analytical Method Volume Intensity (AMVI) are metrics targeting solvent consumption in chromatography operations.

AMVI covers use and waste during sample prep and analysis. It can be used to compare methods and normalizes solvent amounts to the efficiency of the analysis, namely number of peaks obtained.

“It is the first metric I have seen that gives some measure of the analytical chemistry as part of the measure of the green chemistry,” says Douglas Raynie of South Dakota State University. Although AMVI doesn’t directly address solvent identity, it would catch whether switching solvents might increase the amount needed.

A simple graphical guide, the National Environmental Methods Index (NEMI) label developed through the efforts of U.S. agencies and private experts in the U.S., indicates whether a method uses harmful or corrosive chemicals. It also shows the amount and hazard of wastes generated, though it doesn’t look at energy use.

And a collaboration among Gdan´sk University of Technology and others is promoting an analytical Eco-Scale that ranks methods in several categories—reagents, hazard, energy, and waste—according to a cumulative point scale. The Gdan´sk group has also proposed a system for scoring solvents by toxicological and exposure hazards.

The different metrics range in utility, according to Raynie. “Several of them are becoming increasingly complex,” he cautions. “While they provide more information, it means they are not being used.”

Raynie’s group hopes to soon publish a metric that is similar to the NEMI label but more quantitatively looks at waste and energy, as well as health, safety, and environmental factors for an entire analytical approach. “Our philosophy is to keep it simple,” he says. “There are going to be value judgments that have to be made because nothing is going be completely green.”

About 10 years ago, Waters began developing UPLC instruments as an advance over HPLC instruments. Although McCabe admits the company wasn’t necessarily looking to “go green,” using small columns and high pressures to decrease analysis times and increase separations ended up yielding energy and solvent savings.

Over one year, the firm’s Acquity system uses 222 less L of solvent than comparable HPLC runs. This amounts to about $20,000 worth of acetonitrile, the solvent most commonly used in chromatography. “If we could get rid of acetonitrile, that would be huge because it is a hazardous waste,” McCabe says, as is methanol, the next most used solvent.

Reducing solvent use while running analyses is only a drop in the bucket compared with what is generally the least green part of the analytical process: sample preparation. As a result, analytical scientists have been developing a variety of approaches for extraction and sample prep that avoid large quantities of solvents or harmful reagents. Many also try to work with smaller and fewer samples, which can cut down on the length and number of analytical runs.

New miniaturized techniques for synthesis and flow chemistry, along with process analytical methods, can allow for in situ detection and analysis, which don’t require sample handling. Analytical efficiency can increase through approaches that simultaneously detect multiple analytes and multiple parameters. And reduced size and power are key aspects of portable Raman, infrared, and X-ray fluorescence instruments that require no sample prep.

Although it is challenging to evaluate the greenness of any given technology, it can be ever harder to compare different techniques because they are so diverse. Although standard ultraviolet and infrared spectroscopies may require some solvent and use energy, “overall they are fairly green,” Raynie says.

Chemists and chemistry students: Follow key developments connected to the Paris climate change meeting here.

Credit:Ian Langsdon/EPA/Newscom

The same is true for reflectance spectroscopy and other methods that can look at solid samples. But the more complex the analytical technique, “the less green things tend to be,” he adds.

“On the other hand, if you look at nearly all of the developments in analytical chemistry over the past generation, even though they may have been developed to improve the analytical figures of merit and the analytical chemistry, they all tend to have green attributes,” Raynie says. “So I really am a firm believer that if you are doing good analytical chemistry, you are doing green analytical chemistry. They go hand in hand.”


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