Ultra-trace-level determination of cobalt, chromium, and hydrogen peroxide by luminol chemiluminescence detected with a charge-coupled device

A solid-state two-dimensional charge-coupled device (CCD) is used to detect the chemiluminescence of luminol with hydrogen peroxide and a transition metal ion. The chemiluminescence spectra are recorded with the use of trace amounts of metal ions. Excellent linearity, dynamic range, and detection limits are obtained for the total amount of Cr³⁺, CO²⁺, and H₂O₂ analyzed by manual injection. Detection limits on the order of low femto-mole levels of analytes are reported. The utility of CCDs for ultra-low-level light measurements is discussed, and new concepts for 'luminometers,' both wavelength dispersive and nondispersive, are described.