Combination of an intensified charge coupled device with an echelle spectrograph for analysis of colloidal material by laser-induced plasma spectroscopy

An evaluation of the adaptation of an echelle spectrograph to an intensifie d charge coupled device (ICCD) for Laser-induced Plasma Spectroscopy (LIPS) analysis of environmentally relevant heavy metal hydrocolloids deposited o n a membrane filter is presented. For artificial and natural colloids we co uld demonstrate that an echelle spectrograph with an ICCD allows a spectral resolution and enlarged spectral coverage superior to a conventional LIPS detector system based on a Czerny-Turner spectrograph and an intensified di ode-array. Especially natural samples were not accessible with the conventi onal system, while the echelle system permitted an unequivocal multivariate identification of a set of emission lines from a large set of individual e lements. For different heavy metal hydrocolloids we could verify that no si gnificant difference in terms of limit of detection exists between the eche lle/ICCD system and the conventional system. In addition, we illustrated fo r Al2O3 colloids the utilization of the echelle spectrograph for plasma dia gnostics, which can be important for normalization in case of variable plas ma conditions and self-absorption. (C) 1998 Elsevier Science B.V. All right s reserved.