Instrument: Spectrophotometer
An instrument used to measure the relative absorption of electromagnetic radiation of different wavelengths in the near infra-red, visible and ultraviolet wavebands by samples.
Biogenic silica samples (200 mL) were filtered through 0.4 µm 25-mm PCTE filters and then dried at 60°C prior to storage. Samples were digested in 0.2 M NaOH and quantified spectrophotometrically.