Chromatography Forum

Has anybody tried analyzing inorganic anions with an evaporative light scattering detector (ELSD)?

Here are examples for separation of anions on mixed-mode Primesep and Obelisc columns using ELSD as detection:
http://www.sielc.com/application_252.html (ionic liquids)
http://www.sielc.com/application_210.html (sulfate and phosphate ions)
http://www.sielc.com/application_078.html (chloride and nitrate)
http://www.sielc.com/application_173.html (perchlorate, methylsulfonate, nitrate and chloride)
http://www.sielc.com/application_187.html (chloride, bromide, nitrate, etc.)

other applications with ESLD detection:
http://www.sielc.com/Applications_By_Detection.html

regards,

I have done some work in the where I used ELSD for inorganic anions and cations. You need to keep the temparature of the drift tube low for anions like Cl- to detect them with good sensitivity otherwise other ions are easy to detect as non-volatile.

Have a look to the interesting paper below...

Title: Determination of inorganic anions on porous graphitic carbon using evaporative light scattering detection - Use of carboxylic acids as electronic competitors
Author(s): Elfakir, C; Chaimbault, P; Dreux, M
Source: JOURNAL OF CHROMATOGRAPHY A Volume: 829 Issue: 1-2 Pages: 193-199 Published: DEC 31 1998

We worked on separation of both organic and inorganic anions on Acclaim Mixed-Mode columns using ELSD. Currently, we developed a new stationary phase which can separate both anions and cations within the same analysis. Some aspects were presented in the following poster: http://www.dionex.com/en-us/webdocs/675 ... l-note.pdf
(Please pay attention to Figures 6 and 7).

Analysis of inorganic anions by ELSD shouldn't be a problem when the analytes are above 10 ppm. Depending on samples, mobile phase conditions, ELSD setting and the make of ELSD, the sensitivity may vary significantly. For NaCl standard in rather optimized conditions, the detection limits of Na+ and Cl- I could get were 1 ng and 10 ng, respectively.

ELSD is a universal detector (not selective). For high sensivity and high selectivity analysis of inorganc anions and cations, ion-chromatograpgy is a way to go.

Regards,