In this study, we have synthesized a new hyperbranched polyester polymer containing sulfur-pendants (HBPE-S) in the branching points. This HBPE-S polymer is composed of spherical shaped, aliphatic three-dimensional architecture with carboxylic acid groups on the surface. The presence of sulfur pendants in the polymeric cavities demonstrated important role in the effective encapsulation of Bi-DOTA complexes ([Bi] = 5.21 μM), when compared to the previously reported polymer without sulfur pendants (HBPE, [Bi] = 1.07 x 10-3 μM). Higher X-ray blocking capability and excellent X-ray contrast images were obtained from Bi-DOTA encapsulating HBPE-S polymeric nanoparticles when compared with that of HBPE nanoparticles. In addition, the HBPE-S polymer’s spherical structure with amphiphilic cavities allow for the successful encapsulation of anti-tumor drugs and optical dyes, indicating suitable for delivery of wide-range of theranostic agents for cancer diagnosis and treatment. Therapeutic drug taxol encapsulating, folic acid decorated HBPE-S-Fol nanoparticles showed more than 80% of lung carcinoma cell death within 24 h of incubation. Cell viability and microscopic experiments also confirmed for the targeted delivery, thereby minimizing toxicity to healthy tissues. Taken together, new HBPE-S polymer and multimodal theranostic nanoplatforms were synthesized with enhanced X-ray blocking capability for the effective cancer targeting and treatment monitoring.

In this study, we have synthesized new class of hyperstar polyester (HSPE) polymer using a functional A2B monomer and bio‐based sorbitol. We hypothesize that by incorporating sorbitol, its amphiphilic nature will give the polymer greater solubility and allow for the encapsulation of wide range of anti‐cancer therapeutics. We used potassium methoxide to catalyze the melt polymerization reaction. Using the solvent diffusion method, this polymer was used to construct polymeric nanoparticles to encapsulate therapeutics, in one step, for monitoring drug delivery and treatment. The cytotoxicity of our HSPE nanoparticles was evaluated by a cell‐based MTT assays using prostate cancer cells (LNCaP) and healthy cells (CHO). In addition, the level of internalization of our HSPE nanoparticles was evaluated using fluorescence microscopy. Results showed the HSPE nanoparticles have the capability to target and concurrently image and kill cancer cells. Taken together, these studies indicate the successful development of a new drug delivery system and demonstrated its potential use in the pharmaceutical industry and the field of medicine.