Biophysical Interactions of Polyamidoamine Dendrimer Coordinated Fe<SUB>3</SUB>O<SUB>4</SUB> Nanoparticles with Insulin

Abstract

Advanced delivery systems, such as nano/micro carriers have not been studied significantly for their molecular interactions with serum proteins and other biologically relevant macromolecules. Here, we investigated the effect of surface chemistry of iron oxide (Fe3O4) nanoparticles on molecular interactions with human insulin by fluorescence, XRD and FTIR spectroscopy. Nanoparticles of Fe3O4 were chemically modified as Fe3O4-glutathione (GSH) and Fe3O4-GSH-polyamidoamine generation 4 (PAMAM G4) dendrimer. Our results demonstrate that, Fe3O4 and its conjugates such as Fe3O4-GSH, Fe3O4-GSH-G4 quenched insulin fluorescence, indicating strong interactions between insulin protein molecule and Fe3O4. The fluorescence quenching constants Ksv were obtained as 0.0367 x 10(3), 0.0303 x 10(3) and 0.0131 x 10(3) M and the binding constant K were found to be 27.095, 8.404 and 6.026 mM for Fe3O4, Fe3O4-GSH and Fe3O4-GSH-PAMAM G4, respectively. Both the Ksv and K (binding constant) values revealed that the interaction of Fe3O4 with insulin to be stronger over to dendrimer conjugates. In addition, the FTIR spectra suggested that the presence of nanoparticles results in secondary structure alteration in the insulin conformation. The study implies the critical evaluation of new delivery systems in establishing the biocompatibility, especially when delivered by systemic route.

Probing insulin bioactivity in oral nanoparticles produced by ultrasonication-assisted emulsification/internal gelation

“…[1][2][3][4] To ensure enteric protection, recent advances in nanoencapsulation resulted in an increasing growth of innovative formulations such as micro- 5,6 and nanoparticles. 7,8 In drug delivery, nanoparticles have demonstrated numerous advantages over conventional formulations. 9,10 Particle size plays a crucial role in biomedical applications, namely on biorecognition, 11 biodistribution, 12 bioadhesion, 13 biocompatibility, 14 and biodegradation.…”

Hydrothermal Preparation of Five Rare-Earth (Re = Dy, Gd, Ho, Pr, and Sm) Luminescent Cluster-Based Coordination Materials: The First MOFs-based Ratiometric Fluorescent Sensor for Lysine and Bifunctional Sensing Platform for Insulin and Al3+

“…An excellent linear relationship between intensity and insulin concentration is observed ( R 2 = 0.99892). K sv was 2.99 × 10 5 [M] −1 for 2 (Figure ), and using the equation, LOD = 3 S 0 / S ( S 0 is the standard deviation for the blank, S is the slope of calibration curve), the detection limit for insulin should be 0.0012 μM, which reveals higher sensitivity than these previously reported MOFs-based platforms. − These results indicated that MOF2 can be used as a sensing platform for detecting insulin (Ins). Then other human protein hormones such as corticotropin releasing factor (CRF), parathyroid hormone (PTH), and recombination human growth hormone (rHGH) were added into suspensions, respectively.…”

Rational design of polysorbate 80 stabilized human serum albumin nanoparticles tailored for high drug loading and entrapment of irinotecan

“…Fluorescence intensities at 340 nm were recordedas a function of Iro concentration. Further, binding parameters were obtained using Stern-Volmer equation (Samant et al, 2014):…”