Additions and corrections
## Batch-mode mixing on centrifugal microfluidic platforms |

M. Grumann, A. Geipel, L. Riegger, R. Zengerle and J. Ducrée

*Lab Chip*, 2005, **5**, 560 (DOI: 10.1039/b418253g). *Amendment published 4th August 2005*

Eqns. (1), (3) and (5) should read:

On p. 563, Section entitled 'Mixing in alternate spinning mode', the second and third paragraphs should read:

To understand the origin of the mixing effect, we consider the change of the spinning frequency for a given fluid element spaced at a radial distance *r* from the center of rotation (Fig. 4). Inertia tends to stabilize its angular velocity *ω* = 2*π**ν* and thus the angular momentum. According to the given geometry, a difference in the angular momentum Δ*Γ _{ω}* arises from the difference in radial position Δ

This difference in the angular momentum translates into a shear force which drives an advective current within the fluid upon acceleration and deceleration. Mixing is promoted by a twisting pattern of the two fluids shown in Fig. 3B compared to mere deflection of the magnetic beads in constant spinning mode where the angular momentum *Γ _{ω}* does not change in time to eliminate these inertially induced shear forces.

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