Recent progress in upgrading optical microscopy resolution: an opening into biological observations at nanoscale

The advancement of nanotechnology, as a promising novel technology, have been associated with concerns about biosafety and bioenvironmental issues. Specially, since this technology raises the claim of material manipulation in cellular-molecular-level, and improving biological functions of biomaterials with medical and biotechnological aims. In this regard, the safety of nanostructures and sub-cellular components according to the biological observations, and accurate study of biological mechanisms at the nanometer scale is of critical importance. The advantage of optical microscopy as an important tool in development of science is the ability to observe the living sample models, with minimal disruption to their functions, flexibility, sensitivity, and specificity. However, the limitation is the diffraction of light and its effect on the resolution. Recently, improvement of novel super-resolution imaging methods relying on molecules consisting of a labeled structure as nanometer source of light, has led to a significant reduction of resolution gap between fluorescent and electron microscopy. The images obtained by superresolution technique contain valuable information in areas such as chromosome studies, genome mapping, membrane transport, cell division, viral infection and cytotoxicity. This article introduces the latest scientific achievements of optical microscopy resolution improvement to the nanoscale with hope to upgrade the general information in different field of biology and medicine.