A method and apparatus for analyzing a response of a cellular entity to a component of interest are described. The cellular entity may be a cell or an organoid. The method includes processing a heterogeneous population of cellular entities that are combined with the component of interest. An entity flow containing the cellular entities is generated. A morphological image of a portion of the entity flow having a cellular entity is acquired and the cellular entity is identified as belonging to an entity class. The entity flow is provided to a mass spectrometer system that performs an analysis of the cellular entity. The mass spectrometer analysis of the cellular entity can be correlated with the identified entity class. Alternatively, portions of the entity flow are deposited as samples on a sample plate and the mass spectrometer analysis is performed offline, for example, using an ionization process with each sample.