Low toxic graphene quantum dot (GQD) was synthesized by pyrolyzing citric acid in alkaline solution and characterized by ultraviolet--visible (UV–vis) spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM), spectrofluorimetery and dynamic light scattering (DLS) techniques. GQD was used for electrode modification and electro-oxidation of doxorubicin (DOX) at low potential. A substantial decrease in the overvoltage (−0.56 V) of the DOX oxidation reaction (compared to ordinary electrodes) was observed using GQD as coating of glassy carbon electrode (GCE). Differential pulse voltammetry was used to evaluate the analytical performance of DOX in the presence of phosphate buffer solution (pH 4.0) and good limit of detection was obtained by the proposed sensor. Such ability of GQD to promote the DOX electron-transfer reaction suggests great promise for its application as an electrochemical sensor.

No abstract

No abstract

No abstract

Ketoconazole is an important drug with low water solubility. Its low aqueous solubility could be increased using various methods such as by the addition of a pharmaceutical cosolvent. The solubility of ketoconazole in ethanol þ water mixtures at 293.2, 298.2, 303.2, and 308.2 K were determined, and the results showed that the addition of ethanol increased the solubility and the maximum value was obtained at 80% of ethanol. The generated data were mathematically represented using the Jouyban-Acree model within an acceptable accuracy.

No abstract

No abstract

Aims: The efficiency of mesoporous silica magnetic nanoparticles (MSMNP) as a targeted drug-delivery system was investigated. Methods: The superparamagnetic iron oxide nanoparticles (NP) were synthesized, coated with mesoporous silica and conjugated with polyethylene glycol and methotrexate. Next, 1-methyl D tryptophan was loaded into the prepared nanosystems (NS). They were characterized using transmission electron microscopy, scanning electron microscopy, dynamic light scattering, vibrating sample magnetometer, x-ray powder diffraction, Fourier transform-infrared spectroscopy and the Brunauer–Emmett–Teller method and their biological impacts on breast cancer cells were evaluated. Results: The prepared NSs displayed suitable properties and showed enhanced internalization by folate-receptor-expressing cells, exerting efficient cytotoxicity, which was further enhanced by the near-infrared radiation irradiation. Conclusions: On the basis of our findings, the engineered NS is a promising multifunctional nanomedicine/theranostic for solid tumors.