Impact of Surface Functionalization of AgNPs on Binding and Conformational Change of Hemoglobin (Hb) and Hemolytic Behavior

Abstract

With increasing application of silver nanoparticles (AgNPs) in biological sensing, detection, enzyme immunoassays, antimicrobial activity as well as SERS, it has been realised that the toxicity limits their application in biomedicine. However, the interaction of proteins with nanoparticle (NPs) surface possessing different chemical functionalities reduces the potential impact of NPs rendering them biocompatible. Here, we have functionalized the AgNPs with β-hydroxy propyl cyclodextrin (β-HPCD-AgNPs) and studied the conformational changes and thermal stability of haemoglobin (Hb) upon interaction with β-HPCD-AgNPs. Interaction of Hb with borohydride capped AgNPs (BH 4 -AgNPs) was also evaluated. Hb remained in native form upon binding with β-HPCD-AgNPs which is unveiled by UV-vis and fluorescence spectroscopic as well as dynamic light scattering (DLS) studies.However, BH 4 -AgNPs induced unfolding of Hb and reduced the α-helical content following interaction with Hb. Further, the accessibility of tryptophan fluorescence was found to be 33% for β-HPCD-AgNPs quencher, which implies that β-HPCD-AgNPs retains the native conformation of Hb Dichroic study revealed that β-HPCD-AgNPs did not affect thermal stability of Hb, whereas BH 4 -AgNPs decreased the thermal stability of Hb by 5 °C.Haemolysis assay demonstrated the biocompatibility of β-HPCD-AgNPs towards RBC.Functionalization of NPs with controlled surface property thus dictated overall biological reactivity of Hb-AgNPs. Therefore, we trust that the obtained results will help in designing surface functionalized AgNPs for biomedical applications. . Mahato, M.; Pal, P.; Tah, B.; Ghosh, M.; Talapatra, G. B. Study of silver nanoparticle-haemoglobin interaction and composite formation.

Size Dependent Uptake and Hemolytic Effect of Zinc Oxide Nanoparticles on Erythrocytes and Biomedical Potential of ZnO-Ferulic acid Conjugates

“…The bimolecular quenching constant (Kq) was found to be 3.8 × 10 15 , 2.4 × 10 15 , 1.6 × 10 15  M −1  s −1 (Figure S6). These values are higher than diffusion controlled (10 10  M −1  s −1 ) quenching process and it implies the type of quenching is static 26 .…”

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A new strategy for the green synthesis of chondroitin sulfate-reduced gold nanoparticles; in vitro evaluation of synthesized nanoparticles

“…Then, the samples were centrifuged at 13 400 rpm for 5 minutes, and 100 µL of supernatants was added to a well of 96-well plate and absorbance (Optical Density) was measured at 540 nm using a microplate reader, Synergy H1, BioTek. 24 , 25 Hemolytic percent was calculated as follows:…”