Collective motion

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Collective motion is defined as the spontaneous emergence of ordered movement in a system consisting of many self-propelled agents. It can be observed in everyday life, for example in flocks of birds, schools of fish, herds of animals and also in crowds and car traffic. It also appears at the microscopic level: in colonies of bacteria, motility assays and artificial self-propelled particles. [1] [2] [3] The scientific community is trying to understand the universality of this phenomenon. In particular it is intensively investigated in statistical physics and in the field of active matter. Experiments on animals, [4] biological and synthesized self-propelled particles, simulations [5] and theories [6] [7] are conducted in parallel to study these phenomena. One of the most famous models that describes such behavior is the Vicsek model introduced by Tamás Vicsek et al. in 1995. [8]

Contents

Collective behavior of Self-propelled particles

Source: [9]

Just like biological systems in nature, self-propelled particles also respond to external gradients and show collective behavior. Micromotors or nanomotors can interact with self-generated gradients and exhibit schooling and exclusion behavior. [10] For example, Ibele, et al. demonstrated that silver chloride micromotors, in the presence of UV light, interact with each other at high concentrations and form schools. [11] Similar behavior can also be observed with titanium dioxide microparticles. [12] Silver orthophosphate microparticles exhibit transitions between schooling and exclusion behaviors in response to ammonia, hydrogen peroxide, and UV light. [13] [14] This behavior can be used to design a NOR gate since different combinations of the two different stimuli (ammonia and UV light) generate different outputs. Oscillations between schooling and exclusion behaviors are also tunable via changes in hydrogen peroxide concentration. The fluid flows generated by these oscillations are strong enough to transport microscale cargo and can even direct the assembly of close-packed colloidal crystal systems. [15]

Micromotors and nanomotors can also move preferentially in the direction of externally applied chemical gradients, a phenomenon defined as chemotaxis. Chemotaxis has been observed in self-propelled Au-Pt nanorods, which diffuse towards the source of hydrogen peroxide, when placed in a gradient of the chemical. [16] Silica microparticles with Grubbs catalyst tethered to them, also move towards higher monomer concentrations. [17] Enzymes also behave as nanomotors and migrate towards regions of higher substrate concentration, which is known as enzyme chemotaxis. [18] [19] One interesting use of enzyme nanomotor chemotaxis is the separation of active and inactive enzymes in microfluidic channels. [20] Another is the exploration of metabolon formation by studying the coordinated movement of the first four enzymes of the glycolysis cascade: hexokinase, phosphoglucose isomerase, phosphofructokinase and aldolase. [21] [22] More recently, enzyme-coated particles and enzyme-coated liposomes [23] have shown similar behavior in gradients of reactants in microfluidic channels. [24] In general, chemotaxis of biological and synthesized self-propelled particles provides a way of directing motion at the microscale and can be used for drug delivery, sensing, lab-on-a-chip devices and other applications. [25]

See also

Notes

  1. Palacci, Jeremie; Sacanna, Stefano; Steinberg, Asher Preska; Pine, David J.; Chaikin, Paul M. (2013). "Living Crystals of Light-Activated Colloidal Surfers". Science. 339 (6122): 936–940. Bibcode:2013Sci...339..936P. doi:10.1126/science.1230020. PMID   23371555. S2CID   1974474.
  2. Theurkauff, I.; Cottin-Bizonne, C.; Palacci, J.; Ybert, C.; Bocquet, L. (2012). "Dynamic clustering in active colloidal suspensions with chemical signaling". Physical Review Letters. 108 (26): 268303. arXiv: 1202.6264 . Bibcode:2012PhRvL.108z8303T. doi:10.1103/physrevlett.108.268303. PMID   23005020. S2CID   4890068.
  3. Buttinoni, I.; Bialké, J.; Kümmel, F.; Löwen, H.; Bechinger, C.; Speck, T. (2013). "Dynamical clustering and phase separation in suspensions of self-propelled colloidal particles". Physical Review Letters. 110 (23): 238301. arXiv: 1305.4185 . Bibcode:2013PhRvL.110w8301B. doi:10.1103/physrevlett.110.238301. PMID   25167534. S2CID   17127522.
  4. Feder, Toni (2007). "Statistical physics is for the birds". Physics Today. 60 (10): 28–30. Bibcode:2007PhT....60j..28F. doi: 10.1063/1.2800090 .
  5. Grégoire, Guillaume; Chaté, Hugues (2004-01-15). "Onset of Collective and Cohesive Motion". Physical Review Letters. 92 (2): 025702. arXiv: cond-mat/0401208 . Bibcode:2004PhRvL..92b5702G. doi:10.1103/PhysRevLett.92.025702. PMID   14753946. S2CID   37159324.
  6. Toner, John; Tu, Yuhai (1995-12-04). "Long-Range Order in a Two-Dimensional Dynamical $\mathrm{XY}$ Model: How Birds Fly Together". Physical Review Letters. 75 (23): 4326–4329. Bibcode:1995PhRvL..75.4326T. doi:10.1103/PhysRevLett.75.4326. PMID   10059876.
  7. Chaté, H.; Ginelli, F.; Grégoire, G.; Peruani, F.; Raynaud, F. (2008-07-11). "Modeling collective motion: variations on the Vicsek model" (PDF). The European Physical Journal B. 64 (3–4): 451–456. Bibcode:2008EPJB...64..451C. doi:10.1140/epjb/e2008-00275-9. ISSN   1434-6028. S2CID   49363896.
  8. Vicsek, T.; Czirok, A.; Ben-Jacob, E.; Cohen, I.; Shochet, O. (1995). "Novel type of phase transition in a system of self-driven particles". Physical Review Letters. 75 (6): 1226–1229. arXiv: cond-mat/0611743 . Bibcode:1995PhRvL..75.1226V. doi:10.1103/PhysRevLett.75.1226. PMID   10060237. S2CID   15918052.
  9. Altemose, A; Sen, A. (2018). Collective Behaviour of Artificial Microswimmers in Response to Environmental Conditions. Royal Society of Chemistry. pp. 250–283. ISBN   9781788011662.{{cite book}}: CS1 maint: multiple names: authors list (link)
  10. Wang, W.; Duan, W.; Ahmed, S.; Mallouk, T.; Sen, A. (2013). "Small power: Autonomous nano- and micromotors propelled by self-generated gradients". Nano Today. 8 (5): 531. doi:10.1016/j.nantod.2013.08.009.
  11. Ibele, M.; Mallouk, T.; Sen, A. (2009). "Schooling behavior of light-powered autonomous micromotors in water". Angewandte Chemie International Edition. 48 (18): 3308–12. doi:10.1002/anie.200804704. PMID   19338004.
  12. Hong, Y.; Diaz, M.; Córdova-Figueroa, U.; Sen, A. (2010). "Light-Driven Titanium-Dioxide-Based Reversible Microfireworks and Micromotor/Micropump Systems". Advanced Functional Materials. 20 (10): 1568. doi:10.1002/adfm.201000063. S2CID   51990054.
  13. Duan, W.; Liu, R.; Sen, A. (2013). "Transition between collective behaviors of micromotors in response to different stimuli". Journal of the American Chemical Society. 135 (4): 1280–3. doi:10.1021/ja3120357. PMID   23301622.
  14. Altemose, A.; Sánchez-Farrán, M. A.; Duan, W.; Schulz, S.; Borhan, A.; Crespi, V. H.; Sen, A. (2017). "Chemically-controlled spatiotemporal oscillations of colloidal assemblies". Angewandte Chemie International Edition. 56 (27): 7817–7821. doi: 10.1002/anie.201703239 . PMID   28493638.
  15. Altemose, Alicia; Harris, Aaron J.; Sen, Ayusman (2020). "Autonomous Formation and Annealing of Colloidal Crystals Induced by Light-Powered Oscillations of Active Particles". ChemSystemsChem. 2 (1): e1900021. doi: 10.1002/syst.201900021 . ISSN   2570-4206.
  16. Hong, Y.; Blackmann, NMK; Kopp, ND.; Sen, A.; Velegol, D. (2007). "Chemotaxis of nonbiological colloidal rods". Physical Review Letters. 99 (17): 178103. Bibcode:2007PhRvL..99q8103H. doi:10.1103/physrevlett.99.178103. PMID   17995374.
  17. Ravlick, RA.; Sengupta, S.; McFadden, T.; Zhang, H.; Sen, A. (2011). "A Polymerization-Powered Motor". Angewandte Chemie International Edition. 50 (40): 9374–7. doi:10.1002/anie.201103565. PMID   21948434. S2CID   6325323.
  18. Sengupta, S.; Dey, KK.; Muddana, HS.; Tabouillot, T.; Ibele, M.; Butler, PJ.; Sen, A. (2013). "Enzyme Molecules as Nanomotors". Journal of the American Chemical Society. 135 (4): 1406–14. doi:10.1021/ja3091615. PMID   23308365.
  19. Mohajerani, Farzad; Zhao, Xi; Somasundar, Ambika; Velegol, Darrell; Sen, Ayusman (2018-10-30). "A Theory of Enzyme Chemotaxis: From Experiments to Modeling". Biochemistry. 57 (43): 6256–6263. arXiv: 1809.02530 . doi:10.1021/acs.biochem.8b00801. ISSN   0006-2960. PMID   30251529. S2CID   52816076.
  20. Dey, Krishna Kanti; Das, Sambeeta; Poyton, Matthew F.; Sengupta, Samudra; Butler, Peter J.; Cremer, Paul S.; Sen, Ayusman (2014). "Chemotactic Separation of Enzymes". ACS Nano. 8 (12): 11941–11949. doi: 10.1021/nn504418u . ISSN   1936-0851. PMID   25243599.
  21. Zhao, Xi; Palacci, Henri; Yadav, Vinita; Spiering, Michelle M.; Gilson, Michael K.; Butler, Peter J.; Hess, Henry; Benkovic, Stephen J.; Sen, Ayusman (2018). "Substrate-driven chemotactic assembly in an enzyme cascade". Nature Chemistry. 10 (3): 311–317. Bibcode:2018NatCh..10..311Z. doi:10.1038/nchem.2905. ISSN   1755-4330. PMID   29461522.
  22. Metabolons and Supramolecular Enzyme Assemblies. Academic Press. 2019-02-19. ISBN   9780128170755.
  23. Somasundar, Ambika; Ghosh, Subhadip; Mohajerani, Farzad; Massenburg, Lynnicia N.; Yang, Tinglu; Cremer, Paul S.; Velegol, Darrell; Sen, Ayusman (December 2019). "Positive and negative chemotaxis of enzyme-coated liposome motors". Nature Nanotechnology. 14 (12): 1129–1134. Bibcode:2019NatNa..14.1129S. doi:10.1038/s41565-019-0578-8. ISSN   1748-3395. PMID   31740796. S2CID   208168622.
  24. Dey, Krishna K.; Zhao, Xi; Tansi, Benjamin M.; Méndez-Ortiz, Wilfredo J.; Córdova-Figueroa, Ubaldo M.; Golestanian, Ramin; Sen, Ayusman (2015-11-30). "Micromotors Powered by Enzyme Catalysis". Nano Letters. 15 (12): 8311–8315. Bibcode:2015NanoL..15.8311D. doi:10.1021/acs.nanolett.5b03935. ISSN   1530-6984. PMID   26587897.
  25. Zhao, Xi; Gentile, Kayla; Mohajerani, Farzad; Sen, Ayusman (2018-10-16). "Powering Motion with Enzymes". Accounts of Chemical Research. 51 (10): 2373–2381. doi:10.1021/acs.accounts.8b00286. ISSN   0001-4842. PMID   30256612. S2CID   52845451.

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