An Improved Configuration of a Moving Wire Transport Detector

Abstract

An improved design of the transport detector is described that uses a pre-oxidized titanium ribbon as the transport medium. The titanium ribbon has a high loading capacity that permits a large proportion of the total column eluent to be taken into the sensing system. The solute is sensed by pyrolysis and the subsequent detection of pyrolysis products by a miniature argon detector. The pyrolyzer and sensor system is designed to ensure that all the pyrolysis products enter the detector with minimum dilution and band dispersion. As a result, the sensitivity of the detector (or minimum detectable concentration) has been reduced by approximately two orders of magnitude compared with the original design. The sensitivity of the system described to sucrose is 8 x 10(-8) g/mL, which is similar to the sensitivity of the fixed-wavelength UV detector to benzene (approximately 5 x 10(-8) g/mL). It would appear that the new design has potentially a sensitivity at least an order of magnitude lower than that reported here.

Direct‐EI in LC–MS: Towards a universal detector for small‐molecule applications

“…The reliability and robustness of EI has been the main reason for the worldwide success of GC-MS. In spite of a great research effort, the first attempts made to bring the same consistency into the LC-MS world were disappointing, and none of them was even close to the GC-MS performance (Scott & Lawrence, 1970;Scott & Kucera, 1973;Vestal et al, 1974;McFadden et al, 1979;Arpino et al, 1981;Tijssen et al, 1981;Bruins & Drenth, 1983;Arpino & Beaugrand, 1985;Kientz et al, 1996;Dijkstra et al, 1998;Scott, Little, & De la Pena, 2000;Scott, 2003). Only the particle beam (PB) interface, due to its brilliant and efficient interfacing mechanism, gave the possibility to collect EI spectra in an LC application.…”

The UnimasTM detector: A near-universal interface between HPLC and GC

“…Also, the tape temperature is kept below that which would cause softening of the metal and subsequent breakage. The use of a thin, rectangular shaped tape offers significant strength advantages over the wire transport system and has been described in more detail, elsewhere [14]. The titanium tape is only used once to avoid memory effects at high detector sensitivity and because continuous re-oxidation due to cleaning, would substantially weaken the tape, ultimately leading to tape breakage.…”