Ultra vitalux 300 w lamp

With the aim of accelerating the oxidation of β-carotene and simulating the radiation of natural sunlight, an Osram Ultra-Vitalux (300 W) lamp (OSRAM, Múnich, Germany) was used. This blend of radiation is generated by a quartz discharge tube and a tungsten filament [19 (link)]. Nanocapsules with β-carotene and free β-carotene were exposed to the UV radiation (13.6 W) at 37 °C. After irradiation at different times (0 h, 6 h, 12 h, 24 h and 48 h), extraction of β-carotene from 2.5 mg of nanocapsules was carried out. The polymeric capsule wall was opened with water (1 mL) under magnetic stirring (200 RPM, 1 min). β-carotene was extracted from the mixture by adding 0.75 mL of chloroform and separated by centrifugation (10,000 RPM, 1 min). An aliquot of the organic phase was taken and the absorbance was measured at 466 nm in a spectrophotometer (Spectrophotometer UV/VIS4000, DINKO instruments, Barcelona, Spain). Chloroform was used as a blank. Oxidation was reported as a function of the relative β-carotene content (% absorbance). Analyses were made in triplicate.

The photocatalytic activity of cadmium sulfide nanoparticles for hydrogen generation experiments was studied using an Osram Ultra-Vita Lux 300 W lamp with a UV cutter (λ ≥ 420) as a source of visible light, as well as an aqueous solution of glycerin (10% by v/v), which uses glycerin as a sacrificial agent. In the typical photocatalytic experiment, a 30 mg catalyst and 100 mL glycerin solution were placed into a 250 mL tree naked flask and sonicated for 15 min. The photocatalytic reactor was connected to an argon gas flow to remove oxygen molecules, and the dispersed solution was kept in the dark for the first hour. The dispersed solution was magnetic and stirred during throughout experiment. An argon gas flow was fed into the solution through a needle at a rate of 100 mL/min at the degassing (1 h), and 5 mL/min during the photocatalytic experiment. Argon gas served to maintain an inert atmosphere in the reaction system and transport generated hydrogen from the reactor to the chromatograph (Chromos 1000, Dzerzhinsk, Russia).