development of nearfield opticatomic force microscope for biological materials in aqueous solutions this paper reports improvements of optical fiber cantilevers and the scanning nearfield optical microscopy imaging of biological materials in liquid in our scanning nearfield opticalatomicforce microscope snoam the scanning of an optical fiber cantilever over the specimen was controlled by dynamic mode afm to reduce damage to the probe and soft specimens the typical resonant frequency of the optical fiber cantilever was 195 khz while it was 230 khz in air the qfactor of the cantilever depended on the vibration amplitude and was typically 260600 in air and 40240 in water the relationship between the vibration amplitude and the average sampleprobe separation indicated that the cantilever worked in the noncontact mode in water while it worked in the cycliccontact mode in air cultured cells in aqueous solutions were visualized by the snoam indicating that the snoam is suitable to observe soft specimens