Vogel, N. ; Utech, S. ; England, G. T. ; Shirman, T. ; Phillips, K. R. ; Koay, N. ; Burgess, I. B. ; Kolle, M. ; Weitz, D. A. ; Aizenberg, J. Color from hierarchy: Diverse optical properties of micron-sized spherical colloidal assemblies. Proceedings of the National Academy of Sciences 2015, 112, 10845–10850. 2015_pnas_vogel.pdf
Hackelbusch, S. ; Rossow, T. ; Steinhilber, D. ; Weitz, D. A. ; Seiffert, S. Hybrid Microgels with Thermo-Tunable Elasticity for Controllable Cell Confinement. Advanced healthcare materials 2015, 4 1841–1848. 2015_advhealthmater_hackelbusch.pdf
Zhang, H. ; Cockrell, S. K. ; Kolawole, A. O. ; Rotem, A. ; Serohijos, A. W. R. ; Chang, C. B. ; Tao, Y. ; Mehoke, T. S. ; Han, Y. ; Lin, J. S. ; et al. Isolation and analysis of rare norovirus recombinants from co-infected mice using drop-based microfluidics. Journal of virology 2015, JVI–01137. 2015_jvi_zhang.pdf
Abbaspourrad, A. ; Zhang, H. ; Tao, Y. ; Cui, N. ; Asahara, H. ; Zhou, Y. ; Yue, D. ; Koehler, S. A. ; Ung, W. L. ; Heyman, J. ; et al. Label-free single-cell protein quantification using a drop-based mix-and-read system. Scientific reports 2015, 5. 2015_srep_abbaspourrad.pdf
Utech, S. ; Prodanovic, R. ; Mao, A. S. ; Ostafe, R. ; Mooney, D. J. ; Weitz, D. A. Microfluidic Generation of Monodisperse, Structurally Homogeneous Alginate Microgels for Cell Encapsulation and 3D Cell Culture. Advanced healthcare materials 2015, 4 1628–1633. 2015_advancedhealthcarematerials_utech.pdf
Mazutis, L. ; Vasiliauskas, R. ; Weitz, D. A. Microfluidic Production of Alginate Hydrogel Particles for Antibody Encapsulation and Release. Macromolecular Bioscience 2015, n/a–n/a. Publisher's Version 2015_macromolecularbioscience_mazutis.pdf
Chang, C. B. ; Wilking, J. N. ; Kim, S. - H. ; Shum, H. C. ; Weitz, D. A. Monodisperse Emulsion Drop Microenvironments for Bacterial Biofilm Growth. Small 2015, 11, 3954–3961. Publisher's Version 2015_small_chang.pdf
Wagner, O. ; Zieringer, M. ; Duncanson, W. J. ; Weitz, D. A. ; Haag, R. Perfluoroalkyl-Functionalized Hyperbranched Polyglycerol as Pore Forming Agents and Supramolecular Hosts in Polymer Microspheres. International journal of molecular sciences 2015, 16, 20183–20194. 2015_ijms_wagner.pdf
Tao, Y. ; Rotem, A. ; Zhang, H. ; Chang, C. B. ; Basu, A. ; Kolawole, A. O. ; Koehler, S. A. ; Ren, Y. ; Lin, J. S. ; Pipas, J. M. ; et al. Rapid, targeted and culture-free viral infectivity assay in drop-based microfluidics. Lab on a Chip 2015, 15, 3934–3940. 2015_labchip_tao.pdf
Arriaga, L. R. ; Amstad, E. ; Weitz, D. A. Scalable single-step microfluidic production of single-core double emulsions with ultra-thin shells. Lab on a Chip 2015, 15, 3335–3340. 2015_labchip_arriage.pdf
Park, J. - A. ; Kim, J. H. ; Bi, D. ; Mitchel, J. A. ; Qazvini, N. T. ; Tantisira, K. ; Park, C. Y. ; McGill, M. ; Kim, S. - H. ; Gweon, B. ; et al. Unjamming and cell shape in the asthmatic airway epithelium. Nature materials 2015, 14, 1040–1048. 2015_natmater_park_ja.pdf
Han, H. - S. ; Cantalupo, P. G. ; Rotem, A. ; Cockrell, S. K. ; Carbonnaux, M. ; Pipas, J. M. ; Weitz, D. A. Whole-Genome Sequencing of a Single Viral Species from a Highly Heterogeneous Sample. Angewandte Chemie 2015. 2015_angewchem_han.pdf
Tao, Y. ; Rotem, A. ; Zhang, H. ; Cockrell, S. K. ; Koehler, S. A. ; Chang, C. B. ; Ung, L. W. ; Cantalupo, P. G. ; Ren, Y. ; Lin, J. S. ; et al. Artifact-Free Quantification and Sequencing of Rare Recombinant Viruses by Using Drop-Based Microfluidics. ChemBioChem 2015, n/a–n/a. Publisher's Version 2015_chembiochem_tao.pdf
Licup*, A. J. ; Münster*, S. ; Sharma*, A. ; Sheinman, M. ; Jawerth, L. M. ; Fabry, B. ; Weitz, D. A. ; Mackintosh, F. C. Stress controls the mechanics of collagen networks. Proceedings of the National Academy of Sciences 2015, 112, 9573-9578. Publisher's VersionAbstract

Collagen is the main structural and load-bearing element of various connective tissues, where it forms the extracellular matrix that supports cells. It has long been known that collagenous tissues exhibit a highly nonlinear stress–strain relationship, although the origins of this nonlinearity remain unknown. Here, we show that the nonlinear stiffening of reconstituted type I collagen networks is controlled by the applied stress and that the network stiffness becomes surprisingly insensitive to network concentration. We demonstrate how a simple model for networks of elastic fibers can quantitatively account for the mechanics of reconstituted collagen networks. Our model points to the important role of normal stresses in determining the nonlinear shear elastic response, which can explain the approximate exponential relationship between stress and strain reported for collagenous tissues. This further suggests principles for the design of synthetic fiber networks with collagen-like properties, as well as a mechanism for the control of the mechanics of such networks.


[*Equal contribution]

Amstad, E. ; Gopinadhan, M. ; Holtze, C. ; Osuji, C. O. ; Brenner, M. P. ; Spaepen, F. ; Weitz, D. A. Production of amorphous nanoparticles by supersonic spray-drying with a microfluidic nebulator. Science 2015, 349, 956-960. Publisher's VersionAbstract

Amorphous nanoparticles (a-NPs) have physicochemical properties distinctly different from those of the corresponding bulk crystals; for example, their solubility is much higher. However, many materials have a high propensity to crystallize and are difficult to formulate in an amorphous structure without stabilizers. We fabricated a microfluidic nebulator that can produce amorphous NPs from a wide range of materials, even including pure table salt (NaCl). By using supersonic air flow, the nebulator produces drops that are so small that they dry before crystal nuclei can form. The small size of the resulting spray-dried a-NPs limits the probability of crystal nucleation in any given particle during storage. The kinetic stability of the a-NPs—on the order of months—is advantageous for hydrophobic drug molecules.

Soft Poly(dimethylsiloxane) Elastomers from Architecture-Driven Entanglement Free Design
Cai*, L. - H. ; Kodger*, T. E. ; Guerra, R. E. ; Pegoraro, A. F. ; Rubinstein, M. ; Weitz, D. A. Soft Poly(dimethylsiloxane) Elastomers from Architecture-Driven Entanglement Free Design. Advanced Materials 2015, 27, 5132-5140. Publisher's Version 2015_Cai&Kodger_soft Elastomer.pdf

[*Equal contribution] [Featured as Cover Article; Media]

Duncanson, W. J. ; Kodger, T. E. ; Babaee, S. ; Gonzalez, G. ; Weitz, D. A. ; Bertoldi, K. Microfluidic Fabrication and Micromechanics of Permeable and Impermeable Elastomeric Microbubbles. Langmuir 2015, 31, 3489-3493. Publisher's Version 2015_langmuire_duncanson.pdf

PMID: 25730159

Park, J. ; Elmlund, H. ; Ercius, P. ; Yuk, J. M. ; Limmer, D. T. ; Chen, Q. ; Kim, K. ; Han, S. H. ; Weitz, D. A. ; Zettl, A. ; et al. 3D structure of individual nanocrystals in solution by electron microscopy. Science 2015, 349, 290-295. Publisher's Version 2015_science_park.pdf
Park, J. ; Park, H. ; Ercius, P. ; Pegoraro, A. F. ; Xu, C. ; Kim, J. W. ; Han, S. H. ; Weitz, D. A. Direct Observation of Wet Biological Samples by Graphene Liquid Cell Transmission Electron Microscopy. Nano Letters 2015, 15, 4737-4744. Publisher's Version 2015_nanoletter_park.pdf

PMID: 26065925

Rotem, A. ; Ram, O. ; Shoresh, N. ; Sperling, R. A. ; Schnall-Levin, M. ; Zhang, H. ; Basu, A. ; Bernstein, B. E. ; Weitz, D. A. High-Throughput Single-Cell Labeling (Hi-SCL) for RNA-Seq Using Drop-Based Microfluidics. PLoS ONE 2015, 10, e0116328. Publisher's VersionAbstract

The importance of single-cell level data is increasingly appreciated, and significant advances in this direction have been made in recent years. Common to these technologies is the need to physically segregate individual cells into containers, such as wells or chambers of a micro-fluidics chip. High-throughput Single-Cell Labeling (Hi-SCL) in drops is a novel method that uses drop-based libraries of oligonucleotide barcodes to index individual cells in a population. The use of drops as containers, and a microfluidics platform to manipulate them en-masse, yields a highly scalable methodological framework. Once tagged, labeled molecules from different cells may be mixed without losing the cell-of-origin information. Here we demonstrate an application of the method for generating RNA-sequencing data for multiple individual cells within a population. Barcoded oligonucleotides are used to prime cDNA synthesis within drops. Barcoded cDNAs are then combined and subjected to second generation sequencing. The data are deconvoluted based on the barcodes, yielding single-cell mRNA expression data. In a proof-of-concept set of experiments we show that this method yields data comparable to other existing methods, but with unique potential for assaying very large numbers of cells.