Dear All Has anyone out ther any experience with PE-conjugated antibodies in confocal microscopy ? I'm trying to double label cells (using FITC secondary antibodies) and monoclonal coupled to PE. As far as I understand, PE absorbs at both 488 and 565, emitting at 578. So, in principle one should be able to discriminate FITC and PE based on their different emissions, which I can discrminate at the microscope eyepiece. However, at the detector level (on a BioRad 1024) the signal obtained using excitation at 488 or 568 and emission at 578 are quite the same. If anyone has had success using PE-labeled antibodies in double-labeling exepriments on confocal microscopy, please contact me directly. Thanks . Dr. Renato Arruda Mortara Division of Parasitology Universidade Federal de Sao Paulo ESCOLA PAULISTA DE MEDICINA Rua Botucatu, 862 6o. andar 04023-062 Sao Paulo SP Brasil Email [log in to unmask] Fax : 55 11 571-1095 Fone: 55 11 570-8306