Aspects of the invention include hematology analysis reagents, systems and methods that can be used to preserve blood cell morphology and integrity as well as provide sample integrity and optical clarity to facilitate optical analysis of blood samples. In some embodiments, the reagents include a non-phosphate organic buffer and a sphering surfactant. The pH and osmolality of the reagents may be adjusted to desired ranges. In addition, the reagents can be simply diluted with de-ionized water prior to use.