Correction: Seedless assembly of colloidal crystals by inverted micro-fluidic pumping

Abstract

Correction for ‘Seedless assembly of colloidal crystals by inverted micro-fluidic pumping’ by Ran Niu et al., Soft Matter, 2018, 14, 3435–3442.

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In our recent paper¹ we demonstrated the use of inverted electro-osmotic pumps for the seedless assembly of single colloidal crystals. In our devices, gravity plays no role.² One can therefore directly transform the results obtained for the upright geometry by Patrick Kreissl from extensive finite element method (FEM) simulations including full hydrodynamics in ref. 2. Therefore, rather than engaging in new calculations, for the inverted geometry used in ref. 1 we transformed data from ref. 2 and displayed these in Fig. 1b. Unfortunately we also inverted the velocity color scale, such that fast flows in the vicinity of the pump became slow and slow flows not in the vicinity of the pump became fast. In Fig. 1 below, we show the corrected plot. However, this does not influence any of the results or conclusions presented in our paper.¹

Fig. 1 Visualization of the FEM calculated fluid flow generated by an IEX45-based inverted pump at cell height H = 1 mm over a radial range of 2 mm (full range of simulation = 3 mm).² The IEX45 is fixed in the top right corner, the direction of flow is shown with arrows, and the color indicates the magnitude of the local velocity.

The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.

Notes and references

1. R. Niu and T. Palberg, Soft Matter, 2018, 14, 3435.
2. R. Niu, P. Kreissl, A. T. Brown, G. Rempfer, D. Botin, C. Holm, T. Palberg and J. de Graaf, Microfluidic pumping by micromolar salt concentrations, Soft Matter, 2017, 13, 1505.

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