| The development of amphiphilc block copolymers have attracted much attention due to their potential uses in drug delivery and targeting. Very few researches are focused on their prospective applications as fluorescent imaging probes. Although some researcher have reported that fluorescent materials encapsulated in amphiphilic micelles could provide significant opportunities for biological labeling and imaging in biomedical fields, these fluorescent materials, such as organic dyes and quantum dots, suffer from photobleaching, cytotoxicity and lack of biodegradability. A novel and ideal amphiphilic biodegradable photoluminescent polymeric micelle should open new avenues for drug delivery and bioimaging.;The objective of this research was to develop novel biodegradable photoluminescent amphiphilic block polymer (BPABP), comprised of a photoluminescent hydrophobic block, poly(propylene glycol)-citrate-cysteine) (PPGCA-Cys), and a hydrophilic block, poly(ethylene glycol) (PEG). Such photoluminescent polymeric micelles with various block compositions were successfully prepared and characterized using Fourier transformed infrared spectrometer (FTIR), nuclear magnetic resonance (NMR), ultra violet-visible spectrophotometer and fluorospectrophotometer. The results of photoluminescent properties of polymeric micelles supported that BPABP offers advantages over the traditional polymeric micelles due to their unique photoluminescent properties. These photoluminescent properties can be tuned by varying the molecular weight of hydrophobic component of amphiphilic polymers and the choices of monomers, specifically amino acids. Also, the cytotoxicity evaluation indicated a superior in vitro biocompatibility compared to semiconducting quantum dots. The results from dynamic light scattering (DLS) and transmission electron microscopy (TEM) indicated the size range of these micelles were from 120 to 180 nm. The critical micelle concentration (CMC) was varied with the change of hydrophobic chain length. The drug loading efficiency and release behavior in vitro justified their potential uses as drug vehicle. Lastly, we demonstrated the possibility of using BPABPP micelles for in vitro cellular labeling. Therefore, the development of novel BPABP micelle can offer new opportunity in bioimaging and drug delivery. |
