Organic Fluorescent Dye-based Nanomaterials: Advances in the Rational Design for Imaging and Sensing Applications

Abstract

Self-assembled fluorescent nanomaterials based on small-molecule organic dyes are gaining increasing popularity in imaging and sensing applications over the past decade. This is primarily due to their ability to combine spectral property tunability and biocompatibility of small molecule organic fluorophores with brightness, chemical, and colloidal stability of inorganic materials. Such a unique combination of features comes with rich versatility of dye-based nanomaterials: from aggregates of small molecules to sophisticated core-shell nanoarchitectures involving hyperbranched polymers. Along with the ongoing discovery of new materials and better ways of their synthesis, it is very important to continue systematic studies of fundamental factors that regulate the key properties of fluorescent nanomaterials: their size, polydispersity, colloidal stability, chemical stability, absorption and emission maxima, biocompatibility, and interactions with biological interfaces. In this review, we focus on the systematic description of various types of organic fluorescent nanomaterials, approaches to their synthesis, and ways to optimize and control their characteristics. The discussion is built on examples from reports on recent advances in design and applications of such materials. Conclusions made from this analysis allow a perspective on future development of fluorescent nanomaterials design for biomedical and related applications.

Near‐Infrared‐II Nanomaterials for Fluorescence Imaging and Photodynamic Therapy

“…In addition, by adding adenosine triphosphate (ATP), the FL efficiency can be further enhanced due to the additional aggregation of the cationic dye driven by the phosphate anions of ATP. [ 53 ]…”

“…In addition, by adding adenosine triphosphate (ATP), the FL efficiency can be further enhanced due to the additional aggregation of the cationic dye driven by the phosphate anions of ATP. [53] In order to improve the defects of poor water solubility and low QY of OSDs, Tao et al combined the hydrophobic smallmolecule IR-1061 with polyacrylic acid (PAA) to form hydrophilic IR-PEG nanoparticles after DSPE-mPEG coating. [54] Under the excitation of 808 nm wavelength, the emission peak was 1064 nm.…”

Engineering Red-Enhanced and Biocompatible Upconversion Nanoparticles

“…Nanoscale luminescent materials have attracted a special interest in numerous biological applications including biological tissue imaging, super-resolution imaging, sensitive optical sensing, optogenetic (brain studies), and drug delivery. These include organic dyes [ 1 , 2 , 3 ], quantum dots (QDs) [ 4 , 5 ], and fluorescent polymers [ 6 , 7 , 8 ]; however, they are limited by either photostability [ 9 ], toxicity [ 10 , 11 ], or chemical environment sensitivity [ 12 ].…”

Eu-Doped Citrate-Coated Carbonated Apatite Luminescent Nanoprobes for Drug Delivery

“…Fluorescent inorganic and organic nanoparticles including quantum dots, silica, gold, conjugated polymers, organic dyes and structures labeled with organic dyes and monoclonal antibodies have been largely investigated [5][6][7][8][9][10][11]. Among them, and in the context of bioimaging, some organic fluorescent dyes-based nanomaterials have been reported to present favorable characteristics compared to those of inorganic nanoparticles such as higher biodegradability, biocompatibility and lower toxicity [12], especially when compared to quantum dots, which are somehow cytotoxic and show photoblinking [5,13]. In spite of the systems already developed, there is still room for new ones with the goal of improving efficiency and lowering toxicity.…”