Репозиторий Университета

© 2018 American Chemical Society.  Nanoparticle surface engineering can change its chemical identity to enable surface coupling with functional biomolecules. However, common surface coupling methods such as physical adsorption or chemical conjugation often suffer from the low coupling yield, poorly controllable orientation of biomolecules, and steric hindrance during target binding. These issues limit the application scope of nanostructures for theranostics and personalized medicine. To address these shortfalls, we developed a rapid and versatile method of nanoparticle biomodification. The method is based on a SiO 2 -binding peptide that binds to the nanoparticle surface and a protein adaptor system, Barnase∗Barstar protein pair, serving as a "molecular glue" between the peptide and the attached biomolecule. The biomodification procedure shortens to several minutes, preserves the orientation and functions of biomolecules, and enables control over the number and ratio of attached molecules. The capabilities of the proposed biomodification platform were demonstrated by coupling different types of nanoparticles with DARPin9.29 and 4D5scFv - molecules that recognize the human epidermal growth factor receptor 2 (HER2/neu) oncomarker - and by subsequent highly selective immunotargeting of the modified nanoparticles to different HER2/neu-overexpressing cancer cells in one-step or two-step (by pretargeting with HER2/neu-recognizing molecule) modes. The method preserved the biological activity of the DARPin9.29 molecules attached to a nanoparticle, whereas the state-of-the-art carbodiimide 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysulfosuccinimide method of conjugation led to a complete loss of the functional activity of the DARPin9.29 nanoparticle-protein complex. Moreover, the method allowed surface design of nanoparticles that selectively interacted with antigens in complex biological fluids, such as whole blood. The demonstrated capabilities show this method to be a promising alternative to commonly used chemical conjugation techniques in nanobiotechnology, theranostics, and clinical applications.

© 2017 Elsevier Masson SAS A new water-soluble conjugate, consisting of a chlorin-based photosensitizing part, and a 4-arylaminoquinazoline moiety with high potential affinity to an epidermal growth factor receptors (EGFR) and vascular endothelial growth factor receptors (VEGFR), suitable for photodynamic therapy (PDT), was synthesized starting from methylpheophorbide-a in seven steps. An increased accumulation of this compound in A431 cells with high level of EGFR expression, in comparison with CHO and HeLa cells with low EGFR expression was observed. The prepared conjugate exhibits dark and photoinduced cytotoxicity at micromolar concentrations with IC50dark/IC50light ratio of 11–18. In tumor-bearing mice, the conjugate preferentially accumulates in the tumor tissue.