PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Researchers model macroscale plasmonic convection to control fluid and particle motion

2014-01-22
(Press-News.org) Contact information: Kimani Toussaint
ktoussai@illinois.edu
217-244-4088
University of Illinois College of Engineering
Researchers model macroscale plasmonic convection to control fluid and particle motion

Researchers at the University of Illinois at Urbana-Champaign have developed a new theoretical model that explains macroscale fluid convection induced by plasmonic (metal) nanostructures. Their model demonstrates the experimentally observed convection velocities of the order of micrometers per second for an array of gold bowtie nanoantennas (BNAs) coupled to an optically absorptive indium-tin-oxide (ITO) substrate.

"Plasmonics offers numerous opportunities to control fluid motion using light absorption," explained Kimani Toussaint, an associate professor in the Department of Mechanical Science and Engineering (MechSE) at Illinois. "The common understanding in the literature is that the observation of micron/s particle motion in plasmonic tweezers experiments can be accurately modeled if one increased the number of nanostructures—for example, nanoantennas—in the array. We showed that this alone would not explain the phenomena. The ITO is the critical piece to the puzzle,"

"This first collaborative study opens doors to investigate phenomena such as particle separation, nanobubble generation, and optical switching. Computations provide a complementary approach to laboratory observations," said MechSE emeritus professor Pratap Vanka, a co-author of the study. Results of the plasmon-induced convection research, with electrical and computer engineering graduate students Brian Roxworthy and Abdul Bhuiya, have been published in the January issue of Nature Communications.

"This work is the first to establish both theoretically and experimentally that micron/s fluid velocities can be generated using a plasmonic architecture, and provides important insight into the flows affecting particle dynamics in plasmonic optical trapping experiments. And our system can be integrated into microfluidic environments to enable greater dexterity in fluid handling and temperature control," Roxworthy said. The work was funded by the National Science Foundation.

The model uses a set of coupled partial differential equations describing the electromagnetic, heat-transfer, and fluid mechanics phenomena, which is solved using COMSOL Multiphysics, a commercial software package. In the study, gold BNAs are illuminated by 2.5 mW of laser light at three different wavelengths, whereby each wavelength corresponds to be on-, near-, or off-resonance with respect to the plasmon resonance wavelength of the BNAs. A solution containing dielectric, spherical particles with diameters of 1 to 20 microns are placed on the BNAs and used to trace the generated fluid flows.

The development of the model led the researchers to several important conclusions. It allowed them to understand the high-velocity particle motion observed in experiments with plasmonic tweezers, and they realized that inclusion of an ITO layer is critical in distributing the thermal energy created by the BNAs—a fact that has previously been overlooked. Additionally, they found that the ITO alone could be used as a simple, alternative route to achieving fluid convection in lab-on-a-chip environments. The researchers also observed that the plasmonic array alters absorption in the ITO, causing a deviation from Beer–Lambert absorption.



INFORMATION:



ELSE PRESS RELEASES FROM THIS DATE:

New test targets salmonella

2014-01-22
New test targets salmonella Rice University-based research develops fast biosensor for pathogens in food An array of tiny diving boards can perform the Olympian feat of identifying many strains of salmonella at once. The novel biosensor developed by scientists at Rice University ...

NASA still watching an amazingly stubborn, strong tropical low: System 94S

2014-01-22
NASA still watching an amazingly stubborn, strong tropical low: System 94S The tropical low pressure area known as System 94S continues to soak Australia and NASA satellites continue to track its movements. NASA's Terra and Aqua satellites captured visible and infrared ...

UH researcher finds anonymity makes a difference with online comments

2014-01-22
UH researcher finds anonymity makes a difference with online comments Study reports most anonymous comments online are uncivil In a study titled, "Virtuous or Vitriolic: The Effect of Anonymity on Civility in Online Newspaper Reader Comment Boards," University of ...

New web-based course to prevent excessive weight gain may improve health in young adults

2014-01-22
New web-based course to prevent excessive weight gain may improve health in young adults According to a new study in the Journal of Nutrition Education and Behavior PHILADELPHIA, PA, January 21, 2014 – The transition from adolescence to adulthood presents individuals ...

Disadvantaged, non-college bound young adults at risk for excessive weight gain

2014-01-22
Disadvantaged, non-college bound young adults at risk for excessive weight gain Nutritionists develop weight management program relevant to low-income population, according to a new study in the Journal of Nutrition Education and Behavior PHILADELPHIA, PA, January ...

Desire to reproduce drives active nightlife of birds

2014-01-22
Desire to reproduce drives active nightlife of birds URBANA, Ill. – For a non-nocturnal bird, the yellow-breasted chat spends a significant amount of time visiting other birds' territories during ...

Study demonstrates care managers in PCMHs increase improvements in diabetes patients

2014-01-22
Study demonstrates care managers in PCMHs increase improvements in diabetes patients BOSTON – January 21, 2013 – Patient centered medical homes (PCMHs) have been found to be an effective way to help care for patients with chronic diseases such as diabetes. Dr. ...

Study could lead to 'liquid biopsy' tests for bladder cancer

2014-01-22
Study could lead to 'liquid biopsy' tests for bladder cancer MAYWOOD, Il. – Findings from a Loyola University Medical Center study ultimately could lead to tests to screen for and diagnose bladder cancer. Bladder cancer is the fourth most common non-skin cancer. ...

Liquid crystal turns water droplets into 'gemstones,' Penn materials research shows

2014-01-22
Liquid crystal turns water droplets into 'gemstones,' Penn materials research shows Liquid crystals are remarkable materials that combine the optical properties of crystalline solids with the flow properties of liquids, characteristics that come together to enable ...

Mayo Clinic scientists propose a breast cancer drug for bladder cancer patients

2014-01-22
Mayo Clinic scientists propose a breast cancer drug for bladder cancer patients ROCHESTER, Minn. ― Jan. 21, 2014 ― Researchers at Mayo Clinic have found amplification of HER2, a known driver of some breast cancers, in a type of bladder cancer called micropapillary ...

LAST 30 PRESS RELEASES:

What’s behind the enormous increase in early-onset gastrointestinal cancers?

Pharmacogenomics expert advances precision medicine for bipolar disorder

Brazilian researcher explores centenarian stem cells for aging insights

Dr. Xuyu Qian's breakthrough analysis of 18 million brain cells advances understanding of human brain development

Gene networks decode human brain architecture from health to glioma

How artificial light at night damages brain health and metabolism

For ultrasound, ultra-strength not always a good thing

Matching your workouts to your personality could make exercising more enjoyable and give you better results

Study shows people perceive biodiversity

Personality type can predict which forms of exercise people enjoy

People can accurately judge biodiversity through sight and sound

People diagnosed with dementia are living longer, global study shows

When domesticated rabbits go feral, new morphologies emerge

Rain events could cause major failure of Waikīkī storm drainage by 2050

Breakthrough in upconversion luminescence research: Uncovering the energy back transfer mechanism

Hidden role of 'cell protector' opens cancer treatment possibilities

How plants build the microbiome they need to survive in a tough environment

Depression due to politics and its quiet danger to democracy addressed in new book 'The Sad Citizen'

International experts and patients unite to help ensure all patients are fully informed before consenting to new surgical procedures

Melting glaciers could trigger more explosive eruptions globally, finds research

Nearly half of U.S. grandchildren live within 10 miles of a grandparent

Study demonstrates low-cost method to remove CO₂ from air using cold temperatures, common materials

Masonic Medical Research Institute (MMRI) welcomes 13 students to prestigious Summer Fellowship program

Mass timber could elevate hospital construction

A nuanced model of soil moisture illuminates plant behavior and climate patterns

$2.6 million NIH grant backs search for genetic cure in deadly heart disease

Pennsylvania’s medical cannabis program changed drastically when anxiety was added as a qualifying condition

1 in 5 overweight adults could be reclassified with obesity according to new framework

Findings of study on how illegally manufactured fentanyl enters U.S. contradict common assumptions, undermining efforts to control supply

Satellite observations provide insight into post-wildfire forest recovery

[Press-News.org] Researchers model macroscale plasmonic convection to control fluid and particle motion