A technique is presented for aligning, in a desired region within a flow chamber of a flow cell, a non-spherical biological entity carried in a sample. The flow chamber has a rectangular cross-section. A bottom flow input module, a top flow input module and a sample input module provide a viscoelastic first fluid, a second viscoelastic fluid, and the sample, respectively, to the flow chamber. The first and the second viscoelastic fluids laminarly flow along a bottom and a top wall of the flow chamber and the sample laminarly flows sandwiched between them. By controlling rate of flow of the first and/or the second viscoelastic fluids the sample flow, and thus the non-spherical biological entity, is focused in the desired region. A gradient of sheer within the sample flow set up due to the first and second viscoelastic fluids orients the non-spherical biological entity in the desired region.