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A dendrimer is a synthetically made branched molecule. In this work, a family of amphiphilic Janus dendrimers bearing precise carbohydrate residues arranged in a defined sequence – glycodendrimers – were used to make vesicles that could be agglutinated by naturally occurring lectins that binds to carbohydrates. The lectins, called galectins, are human adhesion and growth regulatory lectins. Very small differences in the chemistry of different galectin were detected through differences in agglutination with different Janus glycodendrimers.

Shape morphing systems may find potential application in smart textiles, autonomous robotics, biomedical devices, drug delivery and tissue engineering. Lewis and Mahadevan at the Harvard MRSEC have developed 4-D printing by creating a hydrogel-cellulose fibril ink that could be printed to induce a programmable shape change as recently reported in Nature Materials.

The 6th annual Philadelphia Materials Day was held on Saturday, February 6, 2016 at the Bossone Research Center at Drexel University. This joint venture between Penn and Drexel Universities was attended by over 1100 students and parents. Each year faculty and their students present demos on materials-related themes of interest to K-12 students. The themes this year were: Communications, Earth, Environment, Energy, and Sports.

Optimum function of plasmonic nanocrystal in assembly requires precision control of separation. Often, larger separations are desired while still maintaining order. With our COMPASS collaborators, Hough and Donnio, IRG-4 has developed a new class of building blocks that incorporate dendrimer ligands. Dendrimer-nanocrystal building blocks have diameters controlled by dendrimer “generation.” This work was published in  J. Am. Chem. Soc. 137, 10728–10734 (2015).

The U.S. National Science Foundation has awarded additional funds to support helium conservation in the Property Measurement Shared Experimental Facility (SEF). The SEF hosts over a dozen low temperature measurement capabilities requiring liquid helium.

There is an abiding interest in using nanocrystals as laser gain media due to their tunable emission wavelengths, low cost, and solution processability. However, it has been proven difficult to achieve low lasing thresholds suitable for practical applicatons.  NSF MRSEC members Engel and Talapin showed that colloidal semiconductor nanoplatelets (NPLs) with electronic structure of quantum wells can produce optical gain and lase in the red, yellow, green, and blue regions of the visible spectrum with low thresholds and high gains, both a significant improvement over colloidal quantum dots [1].

Present day silicon chips for communication and computing are densely packed with transistors and other passive elements.

Strong interactions at the interface between a crystalline film and substrate can impart new structure to thin films. Here, a germanium surface (purple atoms) squeezes a BaTiO3 thin film above, revealing a hidden phase not seen in the bulk. The hidden phase of BaTiO3 shows oxygen octahedra cages (shaded in aqua) alternating in size. By combining theory, synchrotron x-ray diffraction, and electron microscopy, a new materials design approach has uncovered hidden traits of a material that can be expressed through articulated forces at an interface.

Siderophores are compounds in microorganisms that bind and store iron. Parallels between the chemistry of compounds secreted by mussels to aid adhesion to rocks, and the chemistry of some siderophores inspired UCSB researchers Butler, Israelachvili, and Waite and their coworkers to study their adhesive properties.

Artificially designed planar devices known as metasurfaces can control the output of an incident beam to generate prechosen patterns.