Ultratrace Analysis of Aqueous Liquids

Application Note B-XRF3001

Introduction

An incident X-ray beam impinges upon the sample at a shallow angle resulting in virtually complete reflection of the excitation beam away from the silicon drift detector (Figure 1). This affords dramatically reduced background contributions in the measured energy dispersive X-ray fluorescence spectra. Ultratrace elemental analysis of the liquid sample becomes possible using the NANOHUNTER II and “Drop and Dry” sample preparation technique.

B-XRF3001 Figure 1 TXRF principle

Figure 1:  TXRF principle 


Measurement and results

According to standards for hazardous pollutants in effluent, set by the Ministry of the Environment in Japan, arsenic (As) and selenium (Se) limits are set below 0.1 mg/L. The spectrum of 10 ppb Se in water solution clearly shows a prominent Kα peak (blue spectrum) relative to the background (red spectrum).

From this measurement, the calculated lower limit of detection (LLD) is about 0.8 ppb. The sample was easily prepared by pipetting 10 µL of aqueous solution onto a glass substrate followed by drying.

Large numbers of samples may be quickly prepared and measured with this “Drop & Dry” sample preparation technique (Figure 2).

B-XRF3001 Figure 2 Drop and Dry preparation

Figure 2:  “Drop and Dry” preparation


B-XRF3001 Figure 3 Spectra of 10 ppb As and Se in the aqueous solution

Figure 3:  Spectra of 10 ppb As and Se in the aqueous solution 

Contact Us

Whether you're interested in getting a quote, want a demo, need technical support, or simply have a question, we're here to help.