Tag Archives: American Chemical Society

Reversing Parkinson’s type symptoms in rats

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Indian scientists have developed a technique for delivering drugs that could reverse Parkinson-like symptoms according to an April 22, 2015 news item on Nanowerk (Note: A link has been removed),

As baby boomers age, the number of people diagnosed with Parkinson’s disease is expected to increase. Patients who develop this disease usually start experiencing symptoms around age 60 or older. Currently, there’s no cure, but scientists are reporting a novel approach that reversed Parkinson’s-like symptoms in rats.

Their results, published in the journal ACS Nano (“Trans-Blood Brain Barrier Delivery of Dopamine-Loaded Nanoparticles Reverses Functional Deficits in Parkinsonian Rats”), could one day lead to a new therapy for human patients.

An April 22, 2015 American Chemical Society press pac news release (also on EurekAlert), which originated the news item, describes the problem the researchers were solving (Note: Links have been removed),

Rajnish Kumar Chaturvedi, Kavita Seth, Kailash Chand Gupta and colleagues from the CSIR-Indian Institute of Toxicology Research note that among other issues, people with Parkinson’s lack dopamine in the brain. Dopamine is a chemical messenger that helps nerve cells communicate with each other and is involved in normal body movements. Reduced levels cause the shaking and mobility problems associated with Parkinson’s. Symptoms can be relieved in animal models of the disease by infusing the compound into their brains. But researchers haven’t yet figured out how to safely deliver dopamine directly to the human brain, which is protected by something called the blood-brain barrier that keeps out pathogens, as well as many medicines. Chaturvedi and Gupta’s team wanted to find a way to overcome this challenge.

The researchers packaged dopamine in biodegradable nanoparticles that have been used to deliver other therapeutic drugs to the brain. The resulting nanoparticles successfully crossed the blood-brain barrier in rats, released its dopamine payload over several days and reversed the rodents’ movement problems without causing side effects.

The authors acknowledge funding from the Indian Department of Science and Technology as Woman Scientist and Ramanna Fellow Grant, and the Council of Scientific and Industrial Research (India).

Here’s a link to and citation for the paper,

Trans-Blood Brain Barrier Delivery of Dopamine-Loaded Nanoparticles Reverses Functional Deficits in Parkinsonian Rats by Richa Pahuja, Kavita Seth, Anshi Shukla, Rajendra Kumar Shukla, Priyanka Bhatnagar, Lalit Kumar Singh Chauhan, Prem Narain Saxena, Jharna Arun, Bhushan Pradosh Chaudhari, Devendra Kumar Patel, Sheelendra Pratap Singh, Rakesh Shukla, Vinay Kumar Khanna, Pradeep Kumar, Rajnish Kumar Chaturvedi, and Kailash Chand Gupta. ACS Nano, Article ASAP DOI: 10.1021/nn506408v Publication Date (Web): March 31, 2015
Copyright © 2015 American Chemical Society

This paper is open access.

Another recent example of breaching the blood-brain barrier, coincidentally, in rats, can be found in my Dec. 24, 2014 titled: Gelatin nanoparticles for drug delivery after a stroke. Scientists are also trying to figure out the the blood-brain barrier operates in the first place as per this April 22, 2015 University of Pennsylvania news release on EurekAlert titled, Penn Vet, Montreal and McGill researchers show how blood-brain barrier is maintained (University of Pennsylvania School of Veterinary Medicine, University of Montreal or Université de Montréal, and McGill University). You can find out more about CSIR-Indian Institute of Toxicology Research here.

Crumpling graphene to create a 3D structure and reflattening it afterwards

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The reseaarchers at the University of Illinois College of Engineering are quite excited about a new technique for crumpling graphene as a Feb. 17, 2015 news item on ScienceDaily reports,

Researchers at the University of Illinois at Urbana-Champaign have developed a unique single-step process to achieve three-dimensional (3D) texturing of graphene and graphite. Using a commercially available thermally activated shape-memory polymer substrate, this 3D texturing, or “crumpling,” allows for increased surface area and opens the doors to expanded capabilities for electronics and biomaterials.

“Fundamentally, intrinsic strains on crumpled graphene could allow modulation of electrical and optical properties of graphene,” explained SungWoo Nam, an assistant professor of mechanical science and engineering at Illinois. “We believe that the crumpled graphene surfaces can be used as higher surface area electrodes for battery and supercapacitor applications. As a coating layer, 3D textured/crumpled nano-topographies could allow omniphobic/anti-bacterial surfaces for advanced coating applications.”

A Feb. 16, 2015 University of Illinois College of Engineering news release (also on EurekAlert), which originated the news item, describes the nature of graphene and what makes this technique so exciting,

Graphene—a single atomic layer of sp2-bonded carbon atoms—has been a material of intensive research and interest over recent years.  A combination of exceptional mechanical properties, high carrier mobility, thermal conductivity, and chemical inertness, make graphene a prime candidate material for next generation optoelectronic, electromechanical, and biomedical applications.

“In this study, we developed a novel method for controlled crumpling of graphene and graphite via heat-induced contractile deformation of the underlying substrate,” explained Michael Cai Wang, a graduate student and first author of the paper, “Heterogeneous, Three-Dimensional Texturing of Graphene,” which appeared in the journal Nano Letters. ”While graphene intrinsically exhibits tiny ripples in ambient conditions, we created large and tunable crumpled textures in a tailored and scalable fashion.”

“As a simpler, more scalable, and spatially selective method, this texturing of graphene and graphite exploits the thermally induced transformation of shape-memory thermoplastics, which has been previously applied to microfluidic device fabrication, metallic  film patterning, nanowire assembly, and robotic self-assembly applications,” added Nam, whose group has filed a patent for their novel strategy. “The thermoplastic nature of the polymeric substrate also allows for the crumpled graphene morphology to be arbitrarily re-flattened at the same elevated temperature for the crumpling process.”

“Due to the extremely low cost and ease of processing of our approach, we believe that this will be a new way to manufacture nanoscale topographies for graphene and many other 2D and thin-film materials.”

The researchers are also investigating the textured graphene surfaces for 3D sensor applications.

“Enhanced surface area will allow even more sensitive and intimate interactions with biological systems, leading to high sensitivity devices,” Nam said.

The funding agencies for this project were unexpectedly interesting (to me), from the news release,

Funding for this research was provided through the Air Force Office for Scientific Research, American Chemical Society and Brain Research Foundation. [emphasis mine] In addition to Wang, co-authors from Nam’s research group at Illinois include SungGyu Chun, Ryan Han, Ali Ashraf, and Pilgyu Kang.

Here’s a link to and a citation for the paper,

Heterogeneous, Three-Dimensional Texturing of Graphene by Michael Cai Wang, SungGyu Chun, Ryan Steven Han, Ali Ashraf, Pilgyu Kang, and SungWoo Nam. Nano Lett., Article ASAP
DOI: 10.1021/nl504612y Publication Date (Web): February 10, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall.

Dexter Johnson has written a Feb. 20, 2015 post highlighting this work on his Nanoclast blog (on the Institute of Electrical and Electronics Engineers [IEEE] website).

A new approach to heating: warm the clothing not the room

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A Jan. 7, 2015 news item on ScienceDaily describes a new type of textile which could change the way we use heat (energy),

To stay warm when temperatures drop outside, we heat our indoor spaces — even when no one is in them. But scientists have now developed a novel nanowire coating for clothes that can both generate heat and trap the heat from our bodies better than regular clothes. They report on their technology, which could help us reduce our reliance on conventional energy sources, in the ACS journal Nano Letters.

A Jan. 7, 2015 American Chemical Society (ACS) news release (also on EurekAlert), which originated the news item, provides more information about energy consumption and the researchers’ proposed solution,

Yi Cui [Stanford University] and colleagues note that nearly half of global energy consumption goes toward heating buildings and homes. But this comfort comes with a considerable environmental cost – it’s responsible for up to a third of the world’s total greenhouse gas emissions. Scientists and policymakers have tried to reduce the impact of indoor heating by improving insulation and construction materials to keep fuel-generated warmth inside. Cui’s team wanted to take a different approach and focus on people rather than spaces.

The researchers developed lightweight, breathable mesh materials that are flexible enough to coat normal clothes. When compared to regular clothing material, the special nanowire cloth trapped body heat far more effectively. Because the coatings are made out of conductive materials, they can also be actively warmed with an electricity source to further crank up the heat. The researchers calculated that their thermal textiles could save about 1,000 kilowatt hours per person every year — that’s about how much electricity an average U.S. home consumes in one month.

Here’s a link to and a citation for the paper,

Personal Thermal Management by Metallic Nanowire-Coated Textile by Po-Chun Hsu, Xiaoge Liu, Chong Liu, Xing Xie, Hye Ryoung Lee, Alex J. Welch, Tom Zhao, and Yi Cui. Nano Lett., Article ASAP DOI: 10.1021/nl5036572 Publication Date (Web): November 30, 2014
Copyright © 2014 American Chemical Society

This paper is behind a paywall.

A dog’s intimate understanding of chemical communication: sniffing butts

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The American Chemical Society (ACS) has made available a video which answers a question almost everyone has asked at one time or another, why do dogs sniff each other’s bottoms?

Here’s how a July 28, 2014 ACS news release describes this line of inquiry,

Here at Reactions, we ask the tough questions to get to the bottom of the biggest scientific quandaries. In that spirit, this week’s video explains why dogs sniff each other’s butts. It’s a somewhat silly question with a surprisingly complex answer. This behavior is just one of many interesting forms of chemical communication in the animal kingdom

Without more ado, the video,

You can find more videos in ACS’s Reactions series here. (This series was formerly known as Bitesize Science.)

Earth Day, Water Day, and every day

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I’m blaming my confusion on the American Chemical Society (ACS) which seemed to be celebrating Earth Day on April 15, 2014 as per its news release highlighting their “Chemists Celebrate Earth Day” video series  while in Vancouver, Canada, we’re celebrating it on April 26, 2014 and elsewhere it seems to be on April 20, this year. Regardless, here’s more about how chemist’s are celebrating from the ACS news release,

Water is arguably the most important resource on the planet. In celebration of Earth Day, the American Chemical Society (ACS) is showcasing three scientists whose research keeps water safe, clean and available for future generations. Geared toward elementary and middle school students, the “Chemists Celebrate Earth Day” series highlights the important work that chemists and chemical engineers do every day. The videos are available at http://bit.ly/CCED2014.

The series focuses on the following subjects:

  • Transforming Tech Toys– Featuring Aydogan Ozcan, Ph.D., of UCLA: Ozcan takes everyday gadgets and turns them into powerful mobile laboratories. He’s made a cell phone into a blood analyzer and a bacteria detector, and now he’s built a device that turns a cell phone into a water tester. It can detect very harmful mercury even at very low levels.
  • All About Droughts – Featuring Collins Balcombe of the U.S. Bureau of Reclamation: Balcombe’s job is to keep your drinking water safe and to find new ways to re-use the water that we flush away everyday so that it doesn’t go to waste, especially in areas that don’t get much rain.
  • Cleaning Up Our Water – Featuring Anne Morrissey, Ph.D., of Dublin City University: We all take medicines, but did you know that sometimes the medicine doesn’t stay in our bodies? It’s up to Anne Morrissey to figure out how to get potentially harmful pharmaceuticals out of the water supply, and she’s doing it using one of the most plentiful things on the planet: sunlight.

Sadly, I missed marking World Water Day which according to a March 21, 2014 news release I received was being celebrated on Saturday, March 22, 2014 with worldwide events and the release of a new UN report,

World Water Day: UN Stresses Water and Energy Issues 

Tokyo Leads Public Celebrations Around the World

Tokyo — March 21 — The deep-rooted relationships between water and energy were highlighted today during main global celebrations in Tokyo marking the United Nations’ annual World Water Day.

“Water and energy are among the world’s most pre-eminent challenges. This year’s focus of World Water Day brings these issues to the attention of the world,” said Michel Jarraud, Secretary-General of the World Meteorological Organization and Chair of UN-Water, which coordinates World Water Day and freshwater-related efforts UN system-wide.

The UN predicts that by 2030 the global population will need 35% more food, 40% more water and 50% more energy. Already today 768 million people lack access to improved water sources, 2.5 billion people have no improved sanitation and 1.3 billion people cannot access electricity.

“These issues need urgent attention – both now and in the post-2015 development discussions. The situation is unacceptable. It is often the same people who lack access to water and sanitation who also lack access to energy, ” said Mr. Jarraud.

The 2014 World Water Development Report (WWDR) – a UN-Water flagship report, produced and coordinated by the World Water Assessment Programme, which is hosted and led by UNESCO – is released on World Water Day as an authoritative status report on global freshwater resources. It highlights the need for policies and regulatory frameworks that recognize and integrate approaches to water and energy priorities.

WWDR, a triennial report from 2003 to 2012, this year becomes an annual edition, responding to the international community’s expression of interest in a concise, evidence-based and yearly publication with a specific thematic focus and recommendations.

WWDR 2014 underlines how water-related issues and choices impact energy and vice versa. For example: drought diminishes energy production, while lack of access to electricity limits irrigation possibilities.

The report notes that roughly 75% of all industrial water withdrawals are used for energy production. Tariffs also illustrate this interdependence: if water is subsidized to sell below cost (as is often the case), energy producers – major water consumers – are less likely to conserve it.  Energy subsidies, in turn, drive up water usage.

The report stresses the imperative of coordinating political governance and ensuring that water and energy prices reflect real costs and environmental impacts.

“Energy and water are at the top of the global development agenda,” said the Rector of United Nations University, David Malone, this year’s coordinator of World Water Day on behalf of UN-Water together with the United Nations Industrial Development Organization (UNIDO).

“Significant policy gaps exist in this nexus at present, and the UN plays an instrumental role in providing evidence and policy-relevant guidance. Through this day, we seek to inform decision-makers, stakeholders and practitioners about the interlinkages, potential synergies and trade-offs, and highlight the need for appropriate responses and regulatory frameworks that account for both water and energy priorities. From UNU’s perspective, it is essential that we stimulate more debate and interactive dialogue around possible solutions to our energy and water challenges.”

UNIDO Director-General LI Yong, emphasized the importance of water and energy for inclusive and sustainable industrial development.

“There is a strong call today for integrating the economic dimension, and the role of industry and manufacturing in particular, into the global post-2015 development priorities. Experience shows that environmentally sound interventions in manufacturing industries can be highly effective and can significantly reduce environmental degradation. I am convinced that inclusive and sustainable industrial development will be a key driver for the successful integration of the economic, social and environmental dimensions,” said Mr. LI.

Rather unusually, Michael Bergerrecently published two Nanowerk Spotlight articles about water (is there theme, anyone?) within 24 hours of each other. In his March 26, 2014 Spotlight article, Michael Berger focuses on graphene and water remediation (Note: Links have been removed),

The unique properties of nanomaterials are beneficial in applications to remove pollutants from the environment. The extremely small size of nanomaterial particles creates a large surface area in relation to their volume, which makes them highly reactive, compared to non-nano forms of the same materials.

The potential impact areas for nanotechnology in water applications are divided into three categories: treatment and remediation; sensing and detection: and pollution prevention (read more: “Nanotechnology and water treatment”).

Silver, iron, gold, titanium oxides and iron oxides are some of the commonly used nanoscale metals and metal oxides cited by the researchers that can be used in environmental remediation (read more: “Overview of nanomaterials for cleaning up the environment”).

A more recent entrant into this nanomaterial arsenal is graphene. Individual graphene sheets and their functionalized derivatives have been used to remove metal ions and organic pollutants from water. These graphene-based nanomaterials show quite high adsorption performance as adsorbents. However they also cause additional cost because the removal of these adsorbent materials after usage is difficult and there is the risk of secondary environmental pollution unless the nanomaterials are collected completely after usage.

One solution to this problem would be the assembly of individual sheets into three-dimensional (3D) macroscopic structures which would preserve the unique properties of individual graphene sheets, and offer easy collecting and recycling after water remediation.

…

The March 27, 2014 Nanowerk Spotlight article was written by someone at Alberta’s (Canada) Ingenuity Lab and focuses on their ‘nanobiological’ approach to water remediation (Note: Links have been removed),

At Ingenuity Lab in Edmonton, Alberta, Dr. Carlo Montemagno and a team of world-class researchers have been investigating plausible solutions to existing water purification challenges. They are building on Dr. Montemagno’s earlier patented discoveries by using a naturally-existing water channel protein as the functional unit in water purification membranes [4].

Aquaporins are water-transport proteins that play an important osmoregulation role in living organisms [5]. These proteins boast exceptionally high water permeability (~ 1010 water molecules/s), high selectivity for pure water molecules, and a low energy cost, which make aquaporin-embedded membrane well suited as an alternative to conventional RO membranes.

Unlike synthetic polymeric membranes, which are driven by the high pressure-induced diffusion of water through size selective pores, this technology utilizes the biological osmosis mechanism to control the flow of water in cellular systems at low energy. In nature, the direction of osmotic water flow is determined by the osmotic pressure difference between compartments, i.e. water flows toward higher osmotic pressure compartment (salty solution or contaminated water). This direction can however be reversed by applying a pressure to the salty solution (i.e., RO).

The principle of RO is based on the semipermeable characteristics of the separating membrane, which allows the transport of only water molecules depending on the direction of osmotic gradient. Therefore, as envisioned in the recent publication (“Recent Progress in Advanced Nanobiological Materials for Energy and Environmental Applications”), the core of Ingenuity Lab’s approach is to control the direction of water flow through aquaporin channels with a minimum level of pressure and to use aquaporin-embedded biomimetic membranes as an alternative to conventional RO membranes.

Here’s a link to and a citation for Montemagno’s and his colleague’s paper,

Recent Progress in Advanced Nanobiological Materials for Energy and Environmental Applications by Hyo-Jick Choi and Carlo D. Montemagno. Materials 2013, 6(12), 5821-5856; doi:10.3390/ma6125821

This paper is open access.

Returning to where I started, here’s a water video featuring graphene from the ACS celebration of Earth Day 2014,

Happy Earth Day!

Chemists wish us all a Happy April Fool’s Day with puns!

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The American Chemical Society (ACS) has produced a video of chemistry jokes/puns,

From the March 31, 2014 ACS news release on EurekAlert,

… the American Chemical Society’s (ACS) Reactions video series is celebrating with an episode featuring our favorite chemistry jokes. Which two elements look cute together? Why is father water concerned about his “iced out” son? What do you get when you combine sulfur, tungsten and silver? Get all the punchlines in the latest Reactions episode, available at: http://youtu.be/C5RZRkhk0OM.

Subscribe to the series at Reactions YouTube, and follow us on Twitter @ACSreactions.

Happy April Fool’s Day1