Sidra Nazir

Bio: Sidra Nazir is an academic researcher. The author has contributed to research in topics: Chemistry & Phosphorene. The author has an hindex of 3, co-authored 7 publications receiving 42 citations.

DFT study of the therapeutic potential of phosphorene as a new drug-delivery system to treat cancer

Abstract: In this study, the therapeutic potential of phosphorene as a drug-delivery system for chlorambucil to treat cancer was evaluated. The geometric, electronic and excited state properties of chlorambucil, phosphorene and the phosphorene–chlorambucil complex were evaluated to explore the efficiency of phosphorene as a drug-delivery system. The nature of interaction between phosphorene and chlorambucil is illustrated through a non-covalent interaction (NCI) plot, which illustrated that weak forces of interaction are present between phosphorene and chlorambucil. These weak intermolecular forces are advantageous for an easy offloading of the drug at the target. Frontier molecular orbital analysis revealed that charge was transferred from chlorambucil to phosphorene during excitation from the HOMO to LUMO. The charge transfer was further supplemented by charge-decomposition analysis (CDA). Excited-state calculations showed that the λmax was red-shifted by 79 nm for the phosphorene–chlorambucil complexes. The photo-induced electron-transfer (PET) process was observed for different excited states, which could be well explained visually based on the electron–hole theory. The photo-induced electron transfer suggests that a quenching of fluorescence occurs upon interaction. This study confirmed that phosphorene possesses significant therapeutic potential as a drug-delivery system for chlorambucil to treat cancer. This study will also motivate further exploration of other 2D materials for drug-delivery applications.

Probing the Reactions of Thiourea (CH4N2S) with Metals (X = Au, Hf, Hg, Ir, Os, W, Pt, and Re) Anchored on Fullerene Surfaces (C59X)

Abstract: Upon various investigations conducted in search for a nanosensor material with the best sensing performance, the need to explore these materials cannot be overemphasized as materials associated with best sensing attributes are of vast interest to researchers. Hence, there is a need to investigate the adsorption performances of various metal-doped fullerene surfaces: C59Au, C59Hf, C59Hg, C59Ir, C59Os, C59Pt, C59Re, and C59W on thiourea [SC(NH2)2] molecule using first-principles density functional theory computation. Comparative adsorption study has been carried out on various adsorption models of four functionals, M06-2X, M062X-D3, PBE0-D3, and ωB97XD, and two double-hybrid (DH) functionals, DSDPBEP86 and PBE0DH, as reference at Gen/def2svp/LanL2DZ. The visual study of weak interactions such as quantum theory of atoms in molecule analysis and noncovalent interaction analysis has been invoked to ascertain these results, and hence we arrived at a conclusive scientific report. In all cases, the weak adsorption observed is best described as physisorption phenomena, and CH4N2S@C59Pt complex exhibits better sensing attributes than its studied counterparts in the interactions between thiourea molecule and transition metal-doped fullerene surfaces. Also, in the comparative adsorption study, DH density functionals show better performance in estimating the adsorption energies due to their reduced mean absolute deviation (MAD) and root-mean-square deviation (RMSD) values of (MAD = 1.0305, RMSD = 1.6277) and (MAD = 0.9965, RMSD = 1.6101) in DSDPBEP86 and PBE0DH, respectively.

Plasma-Induced Hierarchical Amorphous Carbon Nitride Nanostructure with Two N2C-Site Vacancies for Photocatalytic H2O2 Production

Abstract: Carbon nitride (CN) with nitrogen vacancy is a robust photocatalyst with proven enhancing H 2 O 2 production ability. However, nitrogen vacancy control is extremely challenging with the majority of reports representing it as a few vacancies. Herein, for the first time, the amorphous CN (ACN) with two N 2 C -site vacancies in one CN unit is prepared by a one-step H 2 plasma approach. First-principles calculations and experimental results provide consistent evidence that two N 2 C vacancies are located in one CN unit structure after amorphous transformation. Plasma-induced ACN is stable with a hierarchical continuous nanosheet network structure and exhibits an ultrahigh specific surface area of ~405.76 m 2 g −1 , which is 83 times higher than that of pristine CN (4.89 m 2 g −1 ) and significantly enhanced photocatalytic H 2 O 2 production, yielding 1874 μmolg −1 h −1 . Besides, the existence potential drop of 2.61 eV for the electrostatic potential in ACN is key to charge carrier separation. Moreover, the amorphous transformation leads to a new strong band tail, which remarkably enhances the absorbance edge of ACN up to 593 nm, resulting in a wider range of visible-light absorption to enhance H 2 O 2 production. The results have provided an effective approach for promoting the practical application of ACN in photocatalytic H 2 O 2 production. Upon the H 2 plasma treatment, the high energetic particles bombarded the N lattice sites of graphitic carbon nitride (GCN) to form an amorphous carbon nitride (ACN) with two N 2 C -site vacancies in one CN unit. The ACN with hierarchical nanostructure exhibits ultra-high specific surface area and photocatalytic activity. • We developed a one-step H 2 plasma treatment to induce hierarchical ACN nanostructure with two N 2 C -site vacancies in one unit of CN structure without element doping. • The plasma-induced ACN is stable with hierarchical continuous nanosheet network structure and exhibits ultrahigh specific surface area and significantly enhanced photocatalytic H 2 O 2 production yielding. • The two N 2 C vacancies in ACN nanostructure are determined by the first-principles calculations and the consistent electronic character of experimental results. • The amorphous transformation of CN leads to a new strong band tail, which remarkably enhances the absorbance edge of ACN up to 593 nm, resulting in a wider range of visible-light absorption.