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Already renowned for human health benefits, green tea could have a new role — along with other natural plant-based substances — in a healthier, more sustainable production of the most widely used family of nanoparticles.
Credit: iStockphoto/Thinkstock

Already renowned for its beneficial effects on human health, green tea could have a new role — along with other natural plant-based substances — in a healthier, more sustainable production of the most widely used family of nanoparticles, scientists say. Published in ACS Sustainable Chemistry & Engineering, their Perspective article concludes that greener methods for making silver nanoparticles are becoming available.

Rajender Varma, Mallikarjuna Nadagouda and colleagues explain that silver nanoparticles are used in a host of products, especially for their ability to kill bacteria and ward off undesirable odors. Those products include antibacterial socks, undergarments and other clothing. Existing processes for making silver nanoparticles require potentially hazardous substances, use a lot of energy and leave behind undesirable byproducts that require special handling. With production expected to increase, scientists are seeking greener ways to make silver nanoparticles.

The article describes how extracts from plants — such as green tea plants, sunflowers, coffee, fruit and peppers — have emerged as possible substitutes that can replace toxic substances normally used to make the nanoparticles. In addition, extracts from bacteria and fungi, as well as natural polymers, like starches, could serve as substitutes. “These newer techniques for greener AgNP synthesis using biorenewable materials appear promising as they do not have any toxic materials deployed during the production process,” the scientists say.

The authors acknowledge funding from the
U.S. Environmental Protection Agency.

Read the abstract, "Greener Techniques for the Synthesis of Silver Nanoparticles Using Plant Extracts, Enzymes, Bacteria, Biodegradable Polymers, and Microwaves."

From the ACS Office of Public Affairs


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Some of the most enthusiastic green chemistry advocates you can find anywhere are the undergraduate ACS Student Chapter members. At the recent ACS National Meeting in New Orleans, I had a chance to meet many of these students and hear what they are doing to promote sustainability and green chemistry in their communities and universities. As we celebrate Earth Day here in the United States, what better time is there to recognize the creativity and passion of the next generation of chemists!

ACS GCI's Jennifer MacKellar and Dr. David Constable presenting a Green Chemistry Award in New Orleans

to Fresno State ACS Student Affiliate President Brittany Bevier (center). Nick L. Mole, the mascot of the
chapter and the San Joaquin Valley Local Section joins on the left
. Photo Credit: Christine Brennan Schmidt


ACS Green Chemistry Student Chapter Award Ceremony


This year there were 56 ACS Student Chapters who were recognized with a Green Chemistry Award. The award signifies that the chapter engaged in at least three green chemistry outreach and educational activities during the school year. ACS GCI Director, Dr. David Constable and ACS GCI Program Manager, Jennifer MacKellar, presented the awards at the ACS Chapter Awards Ceremony in New Orleans.


Catching up with Successful Green Student Chapters


Monday night at the National Meeting is capped by Sci-Mix—a packed celebration of science which included the "Successful Student Chapter" posters among many others. Dr. David Constable (ACS GCI Director), Jennifer MacKellar (ACS GCI Program Manager), and I (ACS GCI Communications Manager) wound our way through the popcorn-strewn isles to talk to some of the many ACS Student Chapters that were presenting on their green chemistry activities. By no means did we chance to speak with all of the chapters, and many others are doing great green chemistry outreach, but the following selection gives you a sense of the enthusiasm these students have for making an impact in their communities.


Pontifical Catholic University of Puerto Rico

José Mercado and Natalia Fernández, PUCPR Green Chemistry Chair, present their poster 'PUCPR Go Green!'


At Pontifical Catholic University of Puerto Rico (PUCPR) students engaged in a wide variety of activities including designing green chemistry t-shirts and participating in an eco-fashion show, hosting guest lectures on topics such as “Conversion of Biomass to Ethanol for a Green Environment and a Sustainable Economy” and “Impact of Climate Change in the Caribbean Region”, and doing green chemistry demonstrations for other students. This is one active group!


Natalia Fernández, the PUCPR ACS Chapter’s Green Chemistry Chair, says, “Last week, we also had a get together in a park close to our school where we did a scavenger hunt using our green chemistry knowledge to go through different challenges. For example, the players had to decipher the 12 Principles of Green Chemistry that were coded. They also had to make an indicator using flowers, and sort waste between recyclable items and garbage.”


“Applying the 12 Principles of Green Chemistry is important because as future scientists, we have a responsibility to demonstrate to others the importance of protecting our planet,” commented José Mercado, one of the PUCPR students at the National Meeting.


Northeastern University

Christine Dunne, NUSAAC chapter President, and Elise Miner, chapter Vice President,
presenting their chapter's poster “Integrating Green Chemistry into Everyday Life.”


Students at Northeastern University Student Affiliates of the American Chemical Society (NUSAAC) celebrated Earth Day by holding a campus event promoting green chemistry awareness and by setting up a table at the Boston Museum of Science to educate children and adults alike on environmentally benign alternatives to traditional cleaning products. Other activities the group organized included bringing speakers to campus, including Dr. Berkeley “Buzz” Cue and Dr. John Warner as well as visiting the Warner Babcock Institute for Green Chemistry. The group also volunteers for Beyond Benign, an organization dedicated to green chemistry education.


“NUSAAC have been pioneers in the green movement on Northeastern's campus and the greater Boston community,” says Dr. Kathleen Cameron, Faculty Advisor in the Dept. of Chemistry. “The group has also been a major player in an effort to make Northeastern University’s chemistry labs more “green” through alternative and new coursework. These efforts earned them the National Green Chemistry Award for which they are most deserving.”


University of Puerto Rico - Aguadilla

Eva Isis Gordian-Rivera and Genesis Millan-Serrano presenting the ACS-UPRAg poster at New Orleans


The University of Puerto Rico – Aguadilla (UPRAg), whose ACS Student Chapter has won the Green Chemistry Award every academic year since 2008-2009, presented a poster demonstrating their green activities. The chapter has a strong commitment to green chemistry and they describe themselves as “a group of scientists with the desire of generating new ways of thinking, creating a movement to help preserve the environment and human health…by giving our community the appropriate education and by explaining the benefit of the Green Chemistry Principles.” As an example of this commitment, the chapter went on a field trip to uncover the chemistry behind the beaches in Puerto Rico and volunteered to do beach conservation. The chapter also publishes a newsletter called “La Idea Química” which features articles and tips on sustainable chemistry.


Angelo State University

Brandon Allen and Marissa Saulnier share Angelo State University’s ACS Chapter’s activities
with ACS GCI Program Manager, Jennifer MacKellar and Director, Dr. David Constable.


At Angelo State University in western Texas, the students will be celebrating Earth Day with a screening of ‘Switch,’ an educational movie about the future of energy and energy efficiency. The group has also done community outreach activities at a city-wide 'Eco Fair', demonstrating a microbial fuel cell (that’s a device that converts chemical energy to electric energy through a bacterial reaction—see this video for an explanation) as well as how polylactic acid (PLA) cups can biodegrade. To reach out to small children, the students put on a ‘Green Chemistry Magic Show.’


In addition to the outreach, there is one sustainability issue at Angelo State that is impossible to ignore: water. Located in a drought stricken region, the city of San Angelo has only 18.2 months of available water supply left. “Water is a critical issue,” says Dr. Edith Osborne, Professor of Chemistry and Faculty Advisor to the chapter. “We want our labs to reflect that we value the water we have.” Finding ways to decrease water consumption in the lab is a top priority. And faced with a very real possibility that there may come a time when the university is required to limit water usage in the buildings, Dr. Osborne says these conservation efforts will make them ready to operate in a water-restricted setting.


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How do you get people to change their habits and adopt more environmentally friendly practices? Well, one biotechnology company in the San Francisco bay area, Genentech, seems to have found the answer. By combining the leadership of a few forward-looking advocates with a whole lot of grassroots volunteerism and a foundation of corporate support, the 15,000 employee strong company has made quick progress in bringing green chemistry and sustainability into its research and development labs.


Laboratories have some of the largest environmental footprints of any workplace. The amount of energy, water, and materials consumed in a lab—and waste generated—typically exceeds other environments. For example, a standard laboratory fume hood running continuously will use 3 to 4 times more energy than an average house. Because of this, labs are also an area in which improvements can have the biggest impact.


At Genentech, sustainability goals are a top priority. In 2012, it became one of a handful of companies that have committed to reducing building energy, water, and waste by 20% in two years as part of the U.S. Green Building Council’s California Best Building Challenge. Two of the five buildings that Genentech has committed are research facilities.


But Genentech takes a broader view on sustainability than just recycling and energy efficiency—as important as that is—to include specific green chemistry principles that apply to the biotech industry. It all started when one of Genentech’s EHS Program Managers, Dr. Tse-Sung Wu was introduced to green chemistry through a presentation that Dr. Berkeley “Buzz” Cue—then chair of the ACS GCI Pharmaceutical Roundtable—gave at a conference. Dr. Wu’s interest was sparked and he pursued the subject matter through contacts at the Berkeley Center for Green Chemistry at UC Berkeley. Dr. Wu saw how green chemistry could be applied at Genentech to further its sustainability efforts in the lab.


As Dr. Wu was envisioning what became the Green BioPharma Program, in the fall of 2011, he sought and received funding for a new role: a Green Chemistry/BioPharma Project Manager. A recently graduated PhD analytical chemist with green chemistry training and experience as an intern in the Genentech labs got the job—Dr. Kristi Budzinski. Dr. Budzinski’s role was to implement a green chemistry inspired program that would engage employees, encourage innovation, provide resources, and develop leaders. Functionally the program would reside within Genentech’s Sustainability Council’s “Green Genes” program, a grassroots sustainability program that started in 2003 and has 1400 volunteer members.



The Green BioPharma Program


“Up to now we’ve had a great sustainability program, but this is the first time we’ve been able to start making inroads into the core work of what we do.” –Dr. Tse-Sung Wu

One aspect of the Green BioPharma Program is to provide voluntary green lab assessments. “We look at everything in the laboratory and give the lab, one, a picture of what its environmental footprint looks like, and two, actions to reduce that footprint based on what they are specifically doing in the lab,” explains Dr. Budzinski. Each assessment covers energy usage, cold storage, waste streams, and procurement policies. Suggested improvements include things like using a new green product, saving energy by turning off unused fume hoods, increasing recycling signage specific to lab type, and making people aware of programs the company has such as surplus chemical sharing program.


So far 15 labs have gone through the assessment, each receiving a “Green Lab” designation upon completion of at least 50% of the action items. The interest has been very high. “It’s almost like there was a pent up demand for this,” says Dr. Wu. “People are very eager to take it upon themselves.” “When we give them the organizational framework, they are very eager to run with it,” adds Dr. Budzinski. addition to the lab assessments, the team is raising awareness of green chemistry through word of mouth opportunities that have in turn spurred innovation. For example, one interested VP of Medicinal Chemistry invited Wu and Budzinski to present green chemistry to their senior staff.  With an understanding of the types of solutions that would resonate with this unit, Wu and Budzinski were able to provide customized information such as alternative solvent selections applicable to medicinal chemistry. The medicinal chemistry team responded enthusiastically. They took it upon themselves to test the proposed solutions, and then went a step further to develop their own green task force that works to test and recommend greener solvents and methods for chromatography.  By raising awareness and uncovering workable solutions, they were soon able convert people initially skeptical to the idea of green chemistry into advocates.


“Six months after our presentation to the medicinal chemists’ all-hands meeting, I was in a research safety team meeting one day and the question was asked, ‘Does anyone have any best practices to share?’ A member of the medicinal chemistry department volunteered, ‘Well, we are doing greener solvents now. Maybe that’s something people would like to know about?’” Dr. Wu recounts. It’s a perfect example of how employees can become “peer resources” for others and share best practices throughout the company.


Another aspect of the Green BioPharma program involves participation in the ACS GCI Pharmaceutical Roundtable. Genentech was integrated into the Roundtable when the company became a member of the Roche Group, an existing Roundtable member, in 2009. Through the Green BioPharma Program, Dr. Budzinski expanded the collaboration by connecting with other Roundtable members and starting a BioPharma focus group in June of 2012. Together, the participating companies are working on a biologic metric for green chemistry—a version of the Process Mass Intensity calculation tool that’s tailored to the manufacturing of large molecule drugs. The focus group is also engaged in developing a green engineering best practices guide for biotech companies.


By leveraging Genentech’s volunteer forces, inspiring employees to innovate, raising awareness in labs, engaging vendors to source greener products, coordinating resources, and collaborating with other companies through the ACS GCI Industrial Roundtable program, Genentech is taking a leadership role in bringing sustainability and green chemistry into the labs. “The core of what we do is to define transformative medicines that will help patients. The goal of this is to make certain we are doing the chemistry just as effectively—we are getting the same or better results—but doing it in a way that benefits the environment,” comments Bruce Roth, VP of Discovery Chemistry.



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By Emily Hong, Yale University


Any college student who has ever had to cook and fend for themselves knows the advantages of one-pot cooking. One-pot cooking means no complex culinary wrangling of ingredients or excessive rounds of prep-work: Drop the goods in a pan, add a little heat, and out comes something delicious. Or at least edible.



Now imagine your one-pot recipe is for converting algae — that's right, the green scummy stuff you find in tide pools or at the lake — into a biofuel that you can pump straight into your car. Sounds more like fantasy than Food Network, am I right?


Well, this is exactly what Julie Zimmerman's group at the Yale Center for Green Engineering and Green Chemistry is working on (I worked as an undergraduate research assistant at the center during my sophomore year). Zimmerman and her collaborators aim to achieve the conversion of biomass to biofuels without having to push the chemistry to extreme heats or conditions, as well as streamline the conversion process for maximum sustainability.



biofuel pic

The idea of biofuels (essentially petrochemical substitutes derived from plants and the like) present some interesting opportunities for chemists and scientists interested in sustainable technologies. A broader shift towards biofuels could reduce our dependence on fossil fuels with a renewable replacement. However, biofuels often rely on not-so-sustainably produced feed stocks that are dependent on fertilizers, pesticides, and energy-intensive conversion processes to extract the valuable compounds from the raw plant mass.


So far, life cycle analyses of conventional biofuel production techniques have shown that the conversion of biomass into usable fuel raises real concerns of energy balance: With conventional techniques, the energy required to convert biomass into fuel could cancel out the environmental benefits of this renewable technology.


In an article that will soon be published in ChemSusChem, Zimmerman and her collaborators describe their method for the conversion of triolein to methyl oleate - the transesterification of a triglyceride - in supercritical carbon dioxide and methanol with a heterogeneous catalyst, which builds on previous work on lipid extraction from wet biomass using similar scCO2 dependent conditions. Together, these techniques represent significant advances towards the development of a one-pot conversion of biomass to biofuels.

Transesterification of Triglycerides

Transesterification of triglycerides with ethanol (Dr. Zimmerman's work uses methanol)
Source: File:Transesterification of triglycerides with ethanol.png - Wikimedia Commons



Now think back to that kitchen analogy. Cooking can lead to co-products: for example, the egg yolks and shells you don’t need in that meringue, or the broth you made as a result of boiling vegetables for dinner. Another major advantage of the Yale group’s extraction approach is the commitment to maximize all possible utilities from the biomass, following the old maxim of “using every part of the buffalo.” While it is the lipid fractions that are converted to biofuels, the Zimmerman group can also retrieve nutraceuticals along with leftover proteins and carbohydrates from algae, which can then be converted for use in animal feels. Evan Beach, the Program Manager and an Associate Research Scientist with the Yale Center for Green Chemistry and Green Engineering, describes these methods within the concept of a “biorefinery,” which further allows for flexibility regarding “what to do with the biomass depending on market conditions and environmental impacts.”


Again, the analogy of cooking is helpful to understand the power of these techniques to turn renewable biomass into usable products. A potato can be mashed, but it can also be used in soups, turned into fries, or be baked and dressed with sour cream depending on the circumstance. Very few people see raw potatoes as delicious, but with the right culinary skills, their unlimited potential for tastiness is unlocked. Zimmerman’s group is harnessing simple principles to literally turn green into to (black) gold and beyond. Their innovations seem to circle back and serve “sustainability” on many different levels. Now there’s something to toast to.


Emily HongEmily Hong is a junior at Yale University from Nashville, TN. While she is currently majoring in Global Affairs, Emily is a lifelong chemistry nerd who loves Chemistry Cat jokes and the smell of benzaldehyde. In the past she has conducted research on the depolymerization of lignin, and she’s interested in the implications of technology and sustainability in the developing world. Her other activities include varsity fencing, coordinating social media for the Yale Admissions Office, and eating French desserts after studying abroad and working at a bakery in Paris.




This blog was co-published in the ACS Undergraduate blog, Reactions

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By John Adams, Marketing and Business Development, BASF Corporation and Orkun Onur, Marketing Manager, Mermet Corporation


Increasing greenhouse gas emissions are among one of the main contributors to global climate change. As the world’s population continues to grow, so does its energy demands. Thus, the development of energy-efficient products is necessary to reduce emissions, save resources and mitigate rising energy costs.—The Chemical Company—is helping to create sustainable solutions to address global challenges such as this through science and innovation. One example is the use of Cool pigments in innovative KoolBlack Technology for coated solar protection fabrics, such as solar shades and awnings. BASF business partner Mermet successfully launched KoolBlack using BASF pigments for its own product line of solar protection fabrics. Their fabrics for shades and awnings let in sunlight without increasing the interior room temperature, thus lowering cooling energy requirements. This application represents a new approach and ancillary benefit to using window shades. Window shades have historically been used to filter light and keep heat out during the day. Today, users can lower or totally restrict light transmittance into a building while also reducing heat build-up.


Mermet initiated this project with BASF due to vigorous testing required to prove the reduction of glare and heat gain from solar radiation offered through its product line. Both companies worked together to develop and optimize the pigments used. The expertise of both parties was utilized to gain fast performance testing and approvals. This patented science changes the long-standing void in the energy saving performance of dark color screens by adding heat reflection properties to the fabric. KoolBlack Technology reflects Near Infrared (NIR) solar radiation, which reduces room temperatures and the Solar Heat Gain. E Screen with KoolBlack Technology, Mermet’s first fabric line with KoolBlack, is GREENGUARD Children and Schools and RoHS Certified and fire rated to NFPA 701 standards like most of Mermet’s other fabrics. GREENGUARD certified Mermet fabrics meet or exceed stringent standards for “low emissions” and are safe to use in all interiors.


This new technology and application is giving Mermet a strong edge in the market by providing comfort and energy savings throughout the year—features that architects and building owners are looking for to create an optimal living environment for consumers. Lower energy consumption not only translates to cost savings, but reduced greenhouse gas emissions. Helping the world’s inhabitants reduce their carbon footprint is one of the ways BASF is creating chemistry for a sustainable future.


For more information about BASF and Mermet, please visit and




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Last month I spoke of a few events I had attended and why these might be of broader interest.  I’d like to beg your indulgence to let me do the same thing again this month.  I think it’s important to highlight the progress being made in sustainable and green chemistry and that message seems to get lost sometimes in the rush of our daily routines.


Prior to the 19th of March I don’t think I had ever heard of the Global Environmental Facility (GEF) an organization that was started by the United Nations Development Program, the UN Environment Program, and the World Bank but is now a separate entity.  It is basically a funding entity for the UN and World Bank to promote environmental programs in developing countries around the world. Prior to the 19th, GEF had little knowledge of green chemistry, so they held a one-day workshop to try and come up to speed on what green chemistry is and look at a few examples of companies that are using green chemistry to make new products or products in a more sustainable way.

By Dr. David C. Constable, Ph.D., ACS GCI Director


I was particularly struck by a presentation made by the CEO of Myriant, Steve Gatto.  Steve, gave an outstanding presentation of Myriant’s vision for developing succinic acid from bio-based feedstocks.  Perhaps the reason I resonated with his story is that he is making the “drop into place” approach to market entry work.  When it comes to most companies trying to enter the biofuels market, they are competing with the petrochemical industry that has been refined, so to speak, over the course of 150 or more years.  It’s a difficult trajectory for a small company to make an entry in a price competitive, highly optimized market, and the commercialization highway is littered with a great many start-ups who had a great vision, but the economics were not in their favor.


What sets Myriant apart in a potentially risky market is that unlike many feedstocks from petroleum, they can produce succinic acid for less than it can be produced from petroleum, and it’s a C-4 chemistry ready for diversification into many different chemicals and potential products.  As a matter of fact, Myriant is in the happy place of having excess demand for a product it has yet to produce.  In addition, its life cycle profile is considerably more beneficial, and it is made from sorghum or other plants–plants that are not competing for an end use as food.


Unlike my experience at GEF where I had not heard of them, I just returned from the ACS National meeting and as usual, there were a considerable number of opportunities to glimpse what is being done in sustainable and green chemistry.  I had the opportunity to attend the Committee on Environmental Improvement’s (CEI) meetings on Saturday and witnessed their activities on public policy, education and member involvement.  We will be working to better coordinate GCI activities with CEI activities as we go forward; there is a great opportunity for synergistic impact. There were also a variety of presentations related to sustainable and green chemistry. I wasn’t able to attend as many sessions as I might have liked, but there were certainly a great breadth of presentations that spanned a range of interests for anyone and everyone in sustainable and green chemistry.


One notable presentation was the Kavli Lecture given by Daniel Nocera on his “Artificial Leaf.” Regardless of what you think about the long-term potential of the approach he has taken to split water, the important take-away for me is that sometimes you have to step back, look at a problem in a new way, and ask fundamental questions that go against existing dogma and paradigms.  Then you have to have the courage of your convictions to carry on.  Many times it means you work in isolation because few see the importance in what you are undertaking.  That seems to be a hallmark of sustainable and green chemistry as the field struggles to gain acceptance as “good science.”   I’m thankful that there are enough researchers who are looking at the world differently, who are asking the right questions, and who are going to be the ones to make a difference.


As always, let me know what you think.





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