Exploration of phosphorene as doxorubicin nanocarrier: An atomistic view from DFT calculations and MD simulations

Theoretical studies of phosphorene as a drug delivery nanocarrier for fluorouracil

The interactions between phosphorene nanosheets (PNSs) and 5-fluorouracil (FLU) were explored using the density functional theory (DFT) method and molecular dynamics (MD) simulations. DFT calculations were performed utilizing M06-2X functional and the 6-31G(d,p) basis set in both gas and solvent phases. Results showed that the FLU molecule is adsorbed horizontally on the PNS surface with an adsorption energy (Eads) of -18.64 kcal mol-1. The energy gap (Eg) between the highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO, respectively) of PNS remains constant after the adsorption process. The adsorption behavior of PNS is not affected by carbon and nitrogen doping. The dynamical behavior of PNS-FLU was studied at T = 298, 310, and 326 K reminiscent of room temperature, body temperature, and temperature of the tumor after exposure to 808 nm laser radiation, respectively. The D value decreases significantly after the equilibration of all systems so that the equilibrated value of D is about 1.1 × 10-6, 4.0 × 10-8, and 5.0 × 10-9 cm2 s-1 at T = 298, 310, and 326 K, respectively. About 60 FLU molecules can be adsorbed on both sides of each PNS, indicating its high loading capacity. PMF calculations demonstrated that the release of FLU from PNS is not spontaneous, which is favorable from a sustained drug delivery point of view.

Fabricating of Fe3O4@Ag-MOF nanocomposite and evaluating its adsorption activity for removal of doxorubicin

The purpose of this research was to investigate the doxorubicin (DOX) adsorption behavior on Fe3O4@Ag-Metal Organic Framework (Fe₃O₄@Ag-MOF). This adsorbent was effectively prepared using a simple synthetic process. Many instruments, including FTIR, XRD, SEM, TEM, and XPS, were used to characterized the new Fe₃O₄@Ag-MOF. Additionally, the presented Fe₃O₄@Ag-surface MOF's area was shown to be 586.06 m2/g with a size of around 43 nm. The composite that was made has magnetic properties that were quite strong (63.3 emu/g). The produced Fe₃O₄@Ag-MOF was discovered to have a fantastic ability to adsorb the anti-cancer drug DOX, with a 1.72 mmol/g (934.85 mg/g) adsorption capacity. On the basis of changes in temperature, pH, and DOX concentration, the DOX adsorption behavior mechanism was investigated. The adsorption capacity of Fe₃O₄@Ag-MOF for DOX was greater at pH 7.0, according to experimental data. The adsorption equilibrium also demonstrated that the Langmuir adsorption was regulated the best fit to the extracted data compared with the other models. Additionally, the activation energy of adsorption for DOX onto Fe₃O₄@Ag-MOF was determined, indicating the chemisorption process. The adsorption kinetics was shown in the well-known kinetic model of the pseudo-second-order. The adsorption thermodynamic measurements were documented according to according to the enthalpy (ΔH°), entropy(ΔS°), and Gibbs free energy (ΔG°) parameters demonstrated that the reaction was endothermic and spontaneous thermodynamic. The adsorption of DOX onto Fe₃O₄@Ag-MOF from real water samples (tap water, effluent wastewater, and influence wastewater) were investigated. It's interesting that the synthetic adsorbent had great recyclability 72.6 percent in the fifth cycle indicating that it was highly recyclable. After adsorption, the typical Fe₃O₄@Ag-MOF XRD peak intensities and locations were mostly unchanged throughout adsorption indicates the crystalline phase remained steady. The results indicated that Fe₃O₄@Ag-MOF were a good candidate for adsorbing the DOX and treating wastewater.

An Update on Graphene Oxide: Applications and Toxicity

Graphene oxide (GO) has attracted much attention in the past few years because of its interesting and promising electrical, thermal, mechanical, and structural properties. These properties can be altered, as GO can be readily functionalized. Brodie synthesized the GO in 1859 by reacting graphite with KClO3 in the presence of fuming HNO3; the reaction took 3-4 days to complete at 333 K. Since then, various schemes have been developed to reduce the reaction time, increase the yield, and minimize the release of toxic byproducts (NO2 and N2O4). The modified Hummers method has been widely accepted to produce GO in bulk. Due to its versatile characteristics, GO has a wide range of applications in different fields like tissue engineering, photocatalysis, catalysis, and biomedical applications. Its porous structure is considered appropriate for tissue and organ regeneration. Various branches of tissue engineering are being extensively explored, such as bone, neural, dentistry, cartilage, and skin tissue engineering. The band gap of GO can be easily tuned, and therefore it has a wide range of photocatalytic applications as well: the degradation of organic contaminants, hydrogen generation, and CO2 reduction, etc. GO could be a potential nanocarrier in drug delivery systems, gene delivery, biological sensing, and antibacterial nanocomposites due to its large surface area and high density, as it is highly functionalized with oxygen-containing functional groups. GO or its composites are found to be toxic to various biological species and as also discussed in this review. It has been observed that superoxide dismutase (SOD) and reactive oxygen species (ROS) levels gradually increase over a period after GO is introduced in the biological systems. Hence, GO at specific concentrations is toxic for various species like earthworms, Chironomus riparius, Zebrafish, etc.