The present invention relates to a bed, in particular a hospital bed, fitted with a plurality of adjacent individual barrier elements along at least one of its longitudinal sides, the barrier elements extending vertically and each occupying a fraction of the length of the bed. It comprises either a half or full bridge connected to each cell of a set of N cells, which are either floating or connected in series. The sensor particles may be employed to sense unknown environmental conditions or analytes in biological or non-biological systems, in vitro or in vivo.