Hp 8453 uv vis spectrophotometer

Determination of the in vitro drug release was performed using USP type II dissolution apparatus Sotax AT7 from Sotax AG, Basel, Switzerland, in 900 mL of 0.1 M hydrochloric acid at 37 °C with a paddle speed of 100 rpm. Sampling was executed every 5 min for the first 20 min, every 15 min of the following 2 h, and continuing with every hour up to 4 h. Dissolution studies were performed in triplicate and the average proportional cumulative drug release was plotted as a function of time. The MSN concentration in the dissolution medium was measured using a HP 8453 UV-Vis Spectrophotometer from Agilent Technologies Inc., Santa Clara, CA, USA, at a wavelength of 223 nm in a 1 cm cell versus a blank solution consisting of 0.1 M hydrochloric acid. The applied calibration range was between 1 and 280 mg/L. The LOD and LOQ were found to be 0.17 mg/mL and 0.50 mg/L, respectively (R² = 0.99997).

The UV-vis spectrum of nanorod aqueous solution (Figure 1) was acquired with an Agilent/HP 8453 UV-vis spectrophotometer (200 nm < λ < 1100 nm, Dublin, Ireland). Extinction spectrum of gold nanorods deposited on glass coverslips (Figure 1) was acquired with an inverted IX-71 Olympus microscope under halogen lamp (100 W) illumination. The spectrum was acquired by directing the light collected by the objective into the entrance of slit of a monochromator (SP-300i, Acton Research, UK) equipped with a thermoelectrically cooled, back illuminated CCD (Spec10:100B, Princeton Instruments, UK).