Abstract: Systems comprising a diffraction grating, a light source configured to illuminate at a limited waveband, an optical detection system configured to detect zero and non-zero diffraction orders of light, and a signal processing unit adapted to analyze zero and non-zero diffraction orders to determine time-dependent changes in effective optical depth are provided. Methods for use of these systems for real-time detection of cell replication, microorganism detection, and for selecting a therapeutic agent for treating a microorganism are also provided.

Abstract: Methods of determining a phenotype of cells in a biological sample are provided. The methods are based measuring a refractive index of said cells based on a diffraction pattern received from a diffraction grating having a plurality of compartments having lateral dimensions such that said cells can fit therein.

Abstract: Methods of determining a phenotype of cells in a biological sample are provided. The methods are based measuring a refractive index of said cells based on a diffraction pattern received from a diffraction grating having a plurality of compartments having lateral dimensions such that said cells can fit therein.

Abstract: Methods and devices for causing uptake of materials by cells, temporary using local chemical environment modification. The modification may be caused chemically by reducing pH. The uptake method is passive and does not require bioactivity of the cells.