Dynamics of adhesion of single liposome at the charged mercury interface is analyzed through its amperometric signal using a reaction kinetics model and a mechanical model. We present analytical solutions of the reaction kinetics model for decoupling and identifying temporal evolution of three distinct states: i) the initial state corresponding to an intact liposome, ii) the intermediate state where the liposome is partly deformed, and iii) the final state of a lipid monolayer. The results obtained with this model indicate that all three states simultaneously evolve from the onset of the adhesion process.
View Article and Find Full Text PDFJ Phys Condens Matter
July 2012
We investigate--using Monte Carlo computer simulations--the phase behaviour of dimeric colloidal molecules on periodic substrates with square symmetry. The molecules are formed in a two-dimensional suspension of like charged colloids subject to periodic external confinement, which can be experimentally realized by optical methods. We study the evolution of positional and orientational order by varying the temperature across the melting transition.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
April 2011
We theoretically and numerically studied ordering of "colloidal ionic clusters" on periodic substrate potentials such as those generated by optical trapping. Each cluster consists of three charged spherical colloids: two negatively and one positively charged. The substrate is a square or rectangular array of traps, each confining one such cluster.
View Article and Find Full Text PDFAn Acad Bras Cienc
March 2010
A two-dimensional colloidal suspension subject to a periodic substrate evolves into a colloidal molecular crystal under situations of strong confinement. We focus on the long-range orientational order thereby emerging, in the ground state. We study by simulations the situations where in each trap lies a pair of identical colloids, or alternatively a pair of oppositely charged macroions.
View Article and Find Full Text PDFTwo-dimensional suspensions of spherical colloids subject to periodic external fields exhibit a rich variety of molecular crystalline phases. We study in simulations the ground state configurations of dimeric and trimeric systems, that are realized on square and triangular lattices, when either two or three macroions are trapped in each external potential minimum. Bipartite orders of the checkerboard or stripe types are reported together with more complex quadripartite orderings, and the shortcomings of envisioning the colloids gathered in a single potential minimum as a composite rigid object are discussed.
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