Influence of surface oxygen clusters upon molecular stacking of paclitaxel over graphene oxide sheets.

Autor: Patil R; UKA Tarsadia University, Maliba Pharmacy College, Gopal-Vidyanagar Campus, Surat 394350, India., Patel H; UKA Tarsadia University, Maliba Pharmacy College, Gopal-Vidyanagar Campus, Surat 394350, India., Pillai SB; Department of Physics, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara 390002, India., Jha PK; Department of Physics, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara 390002, India., Bahadur P; Department of Chemistry, Veer Narmad South Gujarat University, Surat 395007, India., Tiwari S; UKA Tarsadia University, Maliba Pharmacy College, Gopal-Vidyanagar Campus, Surat 394350, India. Electronic address: tiwarisanju@gmail.com.
Jazyk: angličtina
Zdroj: Materials science & engineering. C, Materials for biological applications [Mater Sci Eng C Mater Biol Appl] 2020 Nov; Vol. 116, pp. 111232. Date of Electronic Publication: 2020 Jun 23.
DOI: 10.1016/j.msec.2020.111232
Abstrakt: Aqueous dispersibility of graphene oxide (GO) sheets can be improved through enrichment of oxygen content (oxidation). However, the resulting 'oxygen clusters' are accompanied with numerous point defects, depletive to π-π stacking behavior of sheets. In this work, we have investigated the properties of sheets oxidized with 2, 4, 6, 8, 10 and 12 weight equivalents of KMnO 4 . Sheets were characterized by spectroscopic, X-ray diffraction (XRD) and electron microscopic techniques. Paclitaxel (PLX) was used as a model drug to analyze the changes in the loading efficiency at different levels of oxidation. Density of oxygen clusters increased as we shifted across increasing proportion of KMnO 4 . This was accompanied with increased inter-layer spacing, disruption of pure graphitic domains and changes in hybridization of carbon atoms (sp 2 to sp 3 ). However, these defects exhibited the tendency of saturation at a finite proportion of KMnO 4 . Oxygen groups negatively affected the loading efficiency of sheets for PLX. Improvement in the loading efficiency of reduced GO (rGO) sheets clarified the predominant role of π-π interactions at the surface. Our study reveals that high oxidation may offset the loading potential of highly aqueous dispersible GO sheets. Therefore, the extent of oxidation must be tuned taking into account the availability of H-bond forming groups in the drug molecule.
Competing Interests: Declaration of competing interest All authors have read and approved this submission. We declare no conflict of interest. This declaration is being made by the corresponding author on behalf of co-authors.
(Copyright © 2020 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
Externí odkaz: