Fluorescent organic small molecular nanomaterials, due to their excellence performance in organic electronics and biological sensing, have attracted more and more attention in the fields of chemistry, materials, biology, and so on. In the past years, significant advances in both the experimental and theoretical fronts have been made for the nanomaterials and nanotechnology. However, compared with fluorescent inorganic quantum dots or polymer nanoparticles, fluorescent organic nanoparticles(FONs) which based on π-conjugated systems, are becoming more and more important to bio-imaging, drug carriers and optoelectronic, since the wider variability and flexibility in materials synthesis and nanoparticles preparation of organic molecules. This paper systematically introduces the recent research developments of the design, synthesis, photophysical properties and application of fluorescent organic small molecular nanomaterials. The highlights of this paper are the preparation methods of fluorescent organic small molecular nanomaterials, such as reprecipitation method, ion association method, self-assembly method, micro-emulsion method, laser fabrication method, adsorbent assisted physical vapor deposition method. We briefly conclude the advantages and disadvantages of the above-mentioned synthetic methods. In addition, we also compare the properties of the fluorescent organic small molecular nanomaterials synthesized by different method, and give a brief introduction to their application on organic optoelectronic devices, chemical and biological sensing, bio-imaging and other fields.

Contents
1 Introduction
2 Preparation methods of fluorescent organic small molecular nanomaterials
2.1 Reprecipitation method
2.2 Ion association method
2.3 Self-assembly method
2.4 Micro-emulsion method
2.5 Laser fabrication method
2.6 Adsorbent assisted physical vapor deposition method
3 Conclusions and outlook