The present disclosure relates to optical crosstalk reduction in particle processing (e.g., cytometry including flow cytometry using microfluidic based sorters, drop formation based sorters, and/or cell purification) systems and methods in order to improve performance. More particularly, the present disclosure relates to assemblies, systems and methods for minimizing optical crosstalk during the analyzing, sorting, and/or processing (e.g., purifying, measuring, isolating, detecting, monitoring and/or enriching) of particles (e.g., cells, microscopic particles, etc.). The exemplary systems and methods for crosstalk reduction in particle processing systems (e.g., cell purification systems) may be particularly useful in the area of cellular medicine or the like. The systems and methods may be modular and used singly or in combination to optimize cell purification based on the crosstalk environment and specific requirements of the operator and/or system.