Determination of cadmium using slotted quartz tube atom trap atomic absorption spectrometry and metal coatings

Özcan Gurbetçioğlu, G. Pelin
Flame atomic absorption spectroscopy (FAAS) is a common technique for detecting metals and metalloids in environmental, biological and metallurgical samples. Although it is a rather old technique, it is still very reliable, simple to use and inexpensive. The technique can be used to determine the concentration of over 70 different metals in a solution. However, it has detection limits at mg/L levels. Some atom trapping methods have been developed to reach the detection limits of ng/mL levels. Slotted quartz tube (SQT) is one of these atom trapping methods. It is an important technique, since it is easy to use, applicable in all laboratories, commercially available and economical. This thesis consists of development of a sensitive method for cadmium with the help of SQT atom trap. In this study, it was used for two different purposes. One was for keeping the analyte atoms more in the light path; in other words, for increasing the residence times of analyte atoms in the measurement zone. This first application was provided a 2.9 times enhancement with respect to conventional FAAS. Second application was for trapping the analyte on the surface of the SQT, in other words, for performing on-line preconcentration of cadmium in SQT. In the presence of a lean flame, analyte samples were trapped and collected for a few minutes at a low suction rate. After finishing the collection period, analyte atoms were revolatilized with the help of a small volume of (10-50 µL) methyl isobutyl ketone (MIBK) and a rapid atomization occurred. This introduction also altered the flame composition momentarily and analyte atoms were released from the surface of the SQT. Application of this method enhanced the sensitivity 2065 times with respect to conventional FAAS. Another approach to this type of atom trapping has been investigated also in this study, which was coating of SQT with some metals having low volatility. Therefore, some transition metals were coated to the surface of SQT and among them zirconium was selected as the best coating material as having the most sensitivity enhancement factor. That is why, rest of the study was performed with the Zr coated SQT. The enhancement was 3368 as compared with FAAS. Cd determination with this method provides LOD value of 8 pg/mL and Co value of 19 pg/mL. In order to see the effect of some other type of elements or ions on determination of cadmium, interference study was done.


Determination of silver by chemical vapour generation and atomic absoption spectrometry
Öztürk, Çağla Pınar; Ataman, Osman Yavuz; Department of Chemistry (2004)
A method for determination of silver has been developed based on chemical vapour generation atomic absorption spectrometry (CVGAAS). Volatile species of silver in acidified medium were generated by the reduction of sodium tetrahydroborate; these species were sent to a flame-heated quartz tube atomizer (QTA) following isolation by using a gas-liquid separator. Flow injection (FI) was used for sample introduction. Optimization of parameters such as; concentrations of acid and NaBH4 concentration, flow rates o...
Determination of Arsenobetaine in Fish Tissue by Species Specific Isotope Dilution LC-LTQ-Orbitrap-MS and Standard Addition LC-ICPMS
Yang, Lu; Ding, Jianfu; Maxwell, Paulette; McCooeye, Margaret; Windust, Anthony; Ouerdane, Laurent; Bakirdere, Sezgin; Willie, Scott; Mester, Zoltan (American Chemical Society (ACS), 2011-05-01)
An accurate and precise method for the determination of arsenobetaine (AsB, (CH(3))(3)(+)AsCH(2)COO(-)) in fish samples using exact matching species specific isotope dilution (ID) liquid chromatography LTQ:Orbitrap mass spectrometry (LC-LTQ-Orbitrap-MS) and standard addition LC inductively coupled plasma mass spectrometry (LC-ICPMS) is described. Samples were extracted by sonication for 30 min with high purity deionized water. An in-house synthesized (13)C enriched AsB spike was used for species specific ID...
Determination of germanium at trace levels by chloride generation atomic absorption spectrometry
Kaya, Murat; Volkan, Mürvet; Department of Chemistry (2004)
Trace amounts of germanium is determined by flame atomic absorption spectrometry by utilizing the vaporization of germanium tetrachloride. Using a continuous flow reactor, sample solution is mixed with concentrated hydrochloric acid and heated to 80ð C to form volatile germanium tetrachloride which can be subsequently sent to N2O-C2H2 flame AAS. The necessary conditions for the volatilization of germanium tetrachloride are investigated in detail and the applicability of the method for the determination of t...
Use of multi-walled carbon nanotubes in matrix solid phase dispersion extraction combined with gas chromatography
Njie, Njaw; Aygün, Rüveyde Sezer; Department of Chemistry (2008)
The use of Multi-Walled Carbon Nanotubes (MWCNT) as solid sorbent in Matrix Solid-Phase Dispersion (MSPD) extraction and preconcentration method was presented to determine some commonly used organophosphorus insecticides/OPIs in honey samples using a Gas Chromatography Flame Ionization Detector (GC-FID). OPIs are poisonous compounds used to kill insects and rodents by affecting their nervous system. The limit of detections obtained after MSPD extraction were 7.0 ng/g for Malathion, Malaoxon and Fenitrothion...
Volkan, Mürvet; Ataman, Osman Yavuz (1987-10-01)
Silica modified by the addition of mercapto chelating groups has been developed for the pre-concentration of trace metals from natural waters. This material removes cadmium, copper, lead and zinc from aqueous solution and can be employed for the pre-concentration of these metals by both column and batch techniques. Under column and batch conditions recoveries larger than 95% were common. For batch extractions of cadmium, zinc, copper and lead from sea water, recoveries of 91 ± 5, 98 ± 4, 97 ± 4 and 96 ± 5%,...
Citation Formats
G. P. Özcan Gurbetçioğlu, “Determination of cadmium using slotted quartz tube atom trap atomic absorption spectrometry and metal coatings,” M.S. - Master of Science, Middle East Technical University, 2010.