title: Improved BrdUrd-Hoechst bivariate cell kinetic analysis by helium-cadmium single laser excitation.
abstract: In laser based flow cytometers, UV excitation of Hoechst 33258 and propidium iodide (PI) or ethidium bromide (EB) is performed with 351/364 nm high power lines of UV-capable argon ion lasers, which are expensive and short-lived. In this paper we note for the first time that helium-cadmium lasers emitting 10 to 30 mW at 325 nm are even more superior for cell kinetic bivariate bromodeoxyuridine (BrdUrd)/Hoechst PI or EB cell cycle analysis. HeCd single laser UV excitation gives comparable CVs for cell cycle distributions, and almost normal G2M/G1 ratios of 1.9 to 2.0 for all cell cycles. This is shown for synchronous and asynchronous cell populations on a FACStar+ and an Ortho Cytofluorograf. Therefore we recommend helium-cadmium lasers as low-power, cheap, and long-lived UV excitation sources for the cytochemically simple but high resolution multiparameter BrdUrd-Hoechst cell kinetic analysis.
mesh_terms: D000818:Animals; D006690:Bisbenzimidazole; D001973:Bromodeoxyuridine; D002104:Cadmium; D002453:Cell Cycle; D002478:Cells, Cultured; D004996:Ethidium; D005434:Flow Cytometry / Q000379:methods*; D006371:Helium; D006801:Humans; D007834:Lasers; D007962:Leukocytes / Q000166:cytology; D051379:Mice; D010954:Plasmacytoma / Q000473:pathology; D011419:Propidium; D014407:Tumor Cells, Cultured
chemical_list: D002104:Cadmium; D006371:Helium; D011419:Propidium; D004996:Ethidium; D001973:Bromodeoxyuridine; D006690:Bisbenzimidazole