Boron nitride nanotube-CREKA peptide as an effective target system to metastatic breast cancer

Purpose: The development of nanomaterials that are capable of recognizing disease-specific biomarkers with high sensitivity and specificity is related to several advances in the field of nanomedicine. Furthermore, the targeted delivery of anticancer agents to tumor tissues enhances their efficiency and reduces their toxic side effects. Boron nitride nanotubes (BNNTs) are nanostructured materials, analog to carbon nanotubes, which present good biocompatibility and morphology suitable for tumor cell internalization. CREKA is a pentapeptide that has a high affinity to fibrin, a protein found in the new tumor vessels in the early stages of metastasis and in thrombosis regions. Methods: In this study BNNTs were chemically functionalized with the peptide CREKA, and this system was characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), zeta potential, scanning electron microscopy, and transmission electron microscopy. Results: After the mentioned chemical steps, the FTIR analysis shows an organic phase related to the CREKA, TGA indicates that about 10% of the peptide is firmly attached to BNNT surface. In addition, the radiolabeling process was successful, achieving the purity required for the biodistribution study. In vivo experiments showed that a considerable amount of BNNT-CREKA was accumulated at the tumor and metastasis sites. Conclusion: The present results indicate an effective targeting of the system to tumor and metastasis sites. Further studies can reveal potential applications of functionalized BNNTs in cancer treatment.