Solvent separated before ionization by electron impact

Solvent separated before ionization by electron impact  

Scott et al. used the already known principle of the wire transport detector and adapted it for mass spectrometry. As shown in Fig, 1, a steel wire 

10 and 10 nriHg. For mass spectra to be produced, the sample coated on the wire is volatilized in the ion source by a current passed through the wire. Mass spectra are recorded continuously. Chromatograms are reconstructed from the total ion current and mass fragmentograms plotted by means of an on-line computer. The separation, determination and identification of steroids and d1- and tri-peptides were carried out with this liquid chromatograph-mass spectrometer-computer system. The combined system was shown to have a sensitivity of 10 -10 g/ml which is about equal to that of a refractive index detector. 

The work described by McFadden and co-workers is an extension of the wire transport detector (section Z.A.l). Because the wire will transport only about It of the total effluent into the vacuum locks, sample utilization is low. Therefore, the wire was replaced with a stainless-steel ribbon (3.2 mm wide, 0.05 mm thick) such that effluent was carried into the vacuum lock at a rate of 1 ml/min, thus achieving efficient sample transport to the ion source region (Fig. 2). Depending on the nature of the sample, the efficiency of sample vaporization and other operational processes, sample utilization in the range 30-50% was achieved. The detection limit for the system was less than 1 ng for carbaryl, 

Lovins and co-workers described the design and operation of an interface to couple a liquid chromatograph equipped with an ultraviolet detector to a mass spectrometer. This interface serves only for the identification and not for the detection of substance. If a substance of interest is indicated by 

---

Realized on-line combinations of liquid chromatography and mass spectrometry 154 Z.A. Solvent separated before ionization by electron impact 155... 

A. Solvent separated before ionization by electron impact ... 

---