Navigation Links
Two-faced miniatures
Date:11/15/2007

This release is available in German.

Many scientists are working feverishly to develop reliable but simple methods for the production of tiny particles with defined size and shape that are covered with special regular patterns in two or three dimensions and at both the nano- and the microscale. These miniature objects have countless applications in modern technology, from diagnostic systems to the generation of artificial tissues to improved data storage. A team headed by Edwin L. Thomas and Patrick S. Doyle at MIT in Cambridge, Massachusetts (USA) has now developed a new method for the large-scale synthesis of three-dimensionally patterned polymer particles with morphological characteristics in the submicrometer range. As described in the journal Angewandte Chemie, with the use of stop-flow interference lithography, the team has even been able to produce Janus particles, microparticles with two chemically different hemispheres.

Our new method is a combination of phase mask interference lithography and mirofluidic flow lithography, unifying the strengths of these two methods, explain the researchers. Liquid precursors of a polymer whose formation is induced by light are introduced into a microfluidic system (a system of channels that are just a few micrometers wide). The bottom portion of the device is a phase mask with a periodic surface structure. This arrangement is irradiated through a transparency mask that defines the shape of the resulting particles. In a test sample these were triangles with sides of 60 m. Once the parallel light rays pass through the strictly periodic surface structure of the phase mask, the result is a complex three-dimensional distribution of light intensity within the liquid (interference). In regions of high intensity, the polymer precursors are cross-linked to form three-dimensional structures in a solid hydrogel. In this way, the researchers were able to give the triangular particles a knobby, lattice-like structure.

Because this method works continuously, it can attain a very high throughput: Liquid flows in and polymerizes to form particles that are immediately rinsed away when the next portion of liquid followsall in less than a second. In contrast to other techniques, the liquid does not need to be deposited in an even layer on a support and developed stepwise.

In addition, within a microchannel, it is possible to allow two different liquids to flow side by side without mixing. If the transparency mask is adjusted so that the light irradiates a region around the boundary between the two liquids, the process results in Janus particles with two chemically different hemispheres.


'/>"/>

Contact: Edwin L. Thomas
elt@mit.edu
617-253-6901
Wiley-Blackwell
Source:Eurekalert

Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/26/2017)... Yorba Linda, Ca (PRWEB) , ... May 25, ... ... a number of Terumo BCT case studies, describing how process development ... learn from new results of T-cell expansion using a hollow-fiber bioreactor system, along ...
(Date:5/24/2017)... WEST BOUNTIFUL, Utah (PRWEB) , ... May 24, ... ... announces the selection and implementation of CLEARAS Water Recovery’s Advanced Biological Nutrient ... is a key component of a $24 million plant upgrade to sustainably meet ...
(Date:5/24/2017)... , May 23, 2017 As Ebola resurfaces in ... four deaths and 20 suspected cases now reported, a new ... PubMed database, showed a correlation between the 2014 and 2017 ... counts rose sharply in 2012-13, which preceded the 2014 outbreak. ... the Ebola gene Replikin counts in 2014-15, which again precedes ...
(Date:5/23/2017)... ... May 23, 2017 , ... ... month its 20th anniversary, marking the occasion with a strong presence at Bio-IT ... Welcome Reception and further extends an invitation to all attendees to view ...
Breaking Biology Technology:
(Date:3/28/2017)... PUNE, India , March 28, 2017 ... (Analog, IP, Biometrics), Hardware (Camera, Monitors, Servers, Storage Devices), ... Maintenance), Vertical, and Region - Global Forecast to 2022", ... 30.37 Billion in 2016 and is projected to reach ... 15.4% between 2017 and 2022. The base year considered ...
(Date:3/24/2017)... 2017 Research and Markets has announced the ... & Trends - Industry Forecast to 2025" report to their ... The Global ... CAGR of around 15.1% over the next decade to reach approximately ... the market estimates and forecasts for all the given segments on ...
(Date:3/22/2017)... , March 21, 2017   Neurotechnology , ... recognition technologies, today announced the release of the ... which provides improved facial recognition using up to ... a single computer. The new version uses deep ... accuracy, and it utilizes a Graphing Processing Unit ...
Breaking Biology News(10 mins):