Colloids

Colloids are particles that have a diameter of between approximately 1 and 1,000 nanometres and that are evenly dispersed in fluids. Colloids are also known as colloidal dispersions because the particles remain dispersed and don't settle to the bottom.

Latest Research and Reviews

  • Research | | open

    The hard disk model is generally applied to study melting in two dimensional colloidal solids, which for idealized 2D systems proceeds through a solid to hexatic - hexatic to fluid process, but impurities perturb the hexatic phase for real systems. The paper reports Monte Carlo and molecular dynamics simulations of a 2D system of polydisperse hard disks, finding that increasing polydispersity decreases stability of hexatic phase, and that even for polydisperse systems there are re-entrant transitions at high density, which is not observed for 3D systems.

    • Pablo Sampedro Ruiz
    • , Qun-li Lei
    •  & Ran Ni
  • Research | | open

    Hydrogel emulsions enable facile loading of bioactive compounds but fabrication methods which allow upscaling and low cytotoxicity are scarce. Here, the authors report a thermally triggered low energy gelation mechanism based on the interaction between a nontoxic Pluronic and nanoemulsion droplets.

    • Seyed Meysam Hashemnejad
    • , Abu Zayed Md Badruddoza
    • , Brady Zarket
    • , Carlos Ricardo Castaneda
    •  & Patrick S. Doyle
  • Research | | open

    The development of functional microrobots calls for new strategies to design locomotion facilitating navigation through complex environments. Here, Lee et al. show how to realize and program helical motion in three dimensions using patchy microspheres under an alternating current electric field.

    • Jin Gyun Lee
    • , Allan M. Brooks
    • , William A. Shelton
    • , Kyle J. M. Bishop
    •  & Bhuvnesh Bharti
  • Research | | open

    It has been previously shown theoretically that the average path length of random walks inside a closed domain is invariant. Here the authors demonstrate that this invariance property can be used to predict the mean residence time of swimming bacteria exploring structured micro-environments.

    • Giacomo Frangipane
    • , Gaszton Vizsnyiczai
    • , Claudio Maggi
    • , Romolo Savo
    • , Alfredo Sciortino
    • , Sylvain Gigan
    •  & Roberto Di Leonardo
  • Research | | open

    Activity often suppresses equilibrium ordering and crystallization in a group of driven or self-propelling colloids. Massana-Cid et al. show tunable self-healing process, where magnetic colloidal rollers are assembled to crystalline carpets upon a balance between magnetism and hydrodynamic interactions.

    • Helena Massana-Cid
    • , Fanlong Meng
    • , Daiki Matsunaga
    • , Ramin Golestanian
    •  & Pietro Tierno

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