Nanocs provides a rich selection of various silica nanoparticles and microbeads that have narrow size distribution, spherical shape and wide selection of their size and surface functionalities. These silica beads are biocompatible and they can be used for cellular and molecular imaging and detection. Silica particles from Nanocs are made from well controlled proprietary process to enure their narrow size distribution and controlled surface functionality. Size of our silica beads ranges from 5 nm to 5 mm. Standard deviation of these silica particles is in the range of 10% of listed size parameter. Our fluorescently labeled and surface functionalized silica particles can be used for flow cytometry and many other biomedical research.