Herein, we report a one-step self-driven process to synthesize multifunctional selleck inhibitor HSSs under an acidic condition with rare-earth ion assistance. Compared with Wang’s report, the synthetic approach of HSSs is simpler. Being synthesized with the assistance of rare-earth ions, the as-prepared HSSs can emit bright fluorescence under ultraviolet radiation, which is convenient to be detected in real time if it is used in biological applications. Typical drug loading and release experiments are carried out using our prepared multifunctional HSSs, SiO2 · Eu2O3 HSs. Methods All chemicals were of analytical grade and purchased from Jinan Camolai
Trading Company (Jinan, China), which were used as received without further purification: tetraethyl orthosilicate (TEOS, 98%), ammonium hydroxide solution (NH3 · H2O, approximately 25% in water), nitric acid (HNO3, 65%), Re2O3, and ethanol (C2H5OH). Rare-earth nitrate solutions [Re(NO3)3 (Re = Y, Eu, La, Sm, Tb, Pr)] with a concentration of 0.04 to 0.08 mol/L were prepared by ourselves. Synthesis of BMS202 research buy monodisperse silica spheres Silica spheres with a diameter of 200 to 500 nm were prepared by the hydrolysis of TEOS in the mixture of ethanol, Temozolomide in vitro water, and ammonium using the Stöber process [37–39]. Synthesis of SiO2 · Re2O3 hollow spheres In a typical synthesis, silica spheres (0.06 g) were added to 20 mL Re(NO3)3 (0.06 mol/L) and stirred for 30 min. The pH of the solution
is 4.5 (adjusted with dilute nitric acid). The mixture was transferred into a Teflon-lined stainless autoclave (capacity 25 mL) and heated at 250°C for 12 h. After the products naturally cooled down to room temperature, they were washed with deionized water
and separated by centrifugation (4,000 rpm) for three times and then dried at 60°C for 4 h in the air. Drug storage and release The steps of drug storage and release are as follows: 1. SiO2 · Eu2O3 HSs (1 g) were added into a 50-mL hexane solution containing 40 mg/mL ibuprofen (IBU). The mixture Tau-protein kinase was sealed and stirred for 24 h. Then the sample was separated by centrifugation and dried at 60°C in the air. The filter was characterized by UV-visible (UV–vis; 264 nm) spectroscopy. 2. The dry SiO2 · Eu2O3 loaded with IBU (0.1 g) was immersed into 50 mL of simulated body fluid (SBF; pH = 7.4) at 37°C and stirred at the rate of 100 rpm. Three milliliters from the top of the solution was used for release measurement at different intervals, and then 3 mL of fresh SBF is added into the solution to keep the volume unchanged. Characterization and instruments The characterization and instruments used are detailed as follows: 1. The samples were characterized by X-ray diffraction (XRD) with a Philips X’Pert Super diffractometer (Amsterdam, The Netherlands) with graphite-monochromatized Cu Kα radiation (λ = 1.54178 Å) in the 2θ range of 1.5° to 10° and 10° to 80°. 2.