Detection of uranium in industrial and mines samples by microwave plasma torch mass spectrometry

Abstract

Microwave plasma torch (MPT), traditionally used as the light source for atomic emission spectrophotometry, has been employed as the ambient ionization source for sensitive detection of uranium in various ground water samples with widely available ion trap mass spectrometer. In the full-scan mass spectra obtained in the negative ion detection mode, uranium signal was featured by the uranyl nitrate complexes (e.g. [UO2 (NO3 )3 ](-) ), which yielded characteristic fragments in the tandem mass spectrometry experiments, allowing confident detection of trace uranium in water samples without sample pretreatment. Under the optimal experimental conditions, the calibration curves were linearly responded within the concentration levels ranged in 10-1000 µg·l(-1) , with the limit of detection (LOD) of 31.03 ng·l(-1) . The relative standard deviations (RSD) values were 2.1-5.8% for the given samples at 100 µg·l(-1) . The newly established method has been applied to direct detection of uranium in practical mine water samples, providing reasonable recoveries 90.94-112.36% for all the samples tested. The analysis of a single sample was completed within 30 s, showing a promising potential of the method for sensitive detection of trace uranium with improved throughput.

Comparative study on ambient ionization methods for direct analysis of navel orange tissues by mass spectrometry

“…Microwave plasma torch‐MS was set up according to previous studies . Briefly, the horizontal and vertical distances between sample and MS ion inlet were 8 and 5 mm, respectively.…”

“…It has been noticed that the sensitivity and selectivity of ionization processes would be seriously affected by the means how the energy was delivered to the targeted analytes , and thus, more ambient ionization methods were developed by innovating the energy/charge transfer process under ambient conditions . For instance, the primary ions generated by electric field (discharge/plasma) have been employed to deliver a certain amount of energy to the analytes in many ambient ionization technologies including direct analysis of real time , low‐temperature plasma , microwave plasma torch (MPT) , plasma‐assisted desorption ionization dielectric barrier discharge ionization and desorption atmospheric pressure chemical ionization (DAPCI) . Similarly, ionic species created by spray‐based technologies such as desorption electrospray ionization , probe electrospray ionization , extractive electrospray ionization , fused droplet electrospray ionization , laser ablation electrospray ionization , paper spray ionization , internal extractive electrospray ionization (iEESI) and easy ambient sonic spray ionization are utilized for transferring a relatively low amount energy to softly ionize the analytes, which is particularly beneficial for ionization of molecules with high polarity.…”

The contribution of photoinduced charge-transfer enhancement to the SERS of uranyl(VI) in a uranyl-Ag2O complex

“…) is one of the most common radioactive pollutants in the environment, and the concerns about its environmental effects and threats to human health have steadily increased over time [1][2][3][4]. Hence, there is an urgent need to precisely and rapidly monitor the content of uranyl ions in environmental aqueous settings, which has resulted in the rapid development of many different uranyl detection methods, such as colorimetric methods [5][6][7], fluorescence methods [8,9], mass spectrometry [10][11][12], and electrochemistry [13,14]. Due to its fast response, high sensitivity, and its successful application in the rapid trace analysis of biological molecules [15][16][17], organic pollutants [18][19][20][21][22], and heavy metal ions [23,24], SERS is expected to become an alternative technique for the detection of uranyl.…”

Considerations for uranium isotope ratio analysis by atmospheric pressure ionization mass spectrometry

“…1, 2 As technologies improve, it is important to evaluate state-of-the-art mass spectrometry (MS) approaches for these aims. As such, the analytical performance of a wide range of isotope ratio (IR)MS-based instrumentation and techniques have been investigated, including secondary ion mass spectrometry (SIMS), 3-10 thermal ionization (TI)MS, 11,12 inductively coupled plasma (ICP)-MS, 13,14 , isotope dilution (ID)MS, 15 extractive electrospray ionization (EESI)-MS, 16, 17 and atmospheric plasma-based sources such as microwave plasma torch (MPT)-MS, 18 solution-cathode glow discharge (SCGD), 19 and liquid sampling-atmospheric pressure glow discharge (LS- APGD) ionization coupled with Orbitrap MS. 20-23…”