Speciation analysis of lead in marine animals by using capillary electrophoresis couple online with inductively coupled plasma mass spectrometry

Abstract

We herein reported a environment-friendly microwave-assisted extraction used to extract trace lead compounds from marine animals and a ultrasensitive method for the analysis of Pb²⁺, trimethyl lead chloride (TML) and triethyl lead chloride (TEL) by using CE-ICP-MS. The extraction method is simple and has a high extracting efficiency. It can be used to completely extract both inorganic lead and organolead in marine animal samples without altering its species. The analytical method has a detection limit as low as 0.012-0.084 ng Pb/mL for Pb²⁺, TML, and TEL, and can be used to determine ultratrace Pb²⁺, TML, and TEL in marine animals directly without any preconcentration. With the help of above methods, we have successfully determined Pb²⁺, TML, and TEL in clam and oyster tissue within 20 min with a RSD (n = 6) < 5% and a recovery of 91-104%. Our results showed that Pb²⁺ was the main species of lead in clam and oyster, and organolead (TML) was only found in oyster. The proposed method provides a realistic approach for the accurate evaluation of lead pollution in seafood.

Species characteristics of lead in sea foods collected from coastal water of Fujian, Southeastern of China

“…To the speciation analysis of lead in sea foods, all Pb species in sea foods samples were completely extracted and each Pb species keep no altering during extraction/analysis process are two key points. As we mentioned above, the microwave-assisted extraction reported in our previous paper were used to extract all Pb species from sea foods samples, and the CE-ICP-MS method reported in the same paper were used for determining Pb 2+ , TML and TEL in this study 26 . In order to confirm the reliability of our methods, the Pb 2+ , TML and TEL in the clam sample ( Paphia undulate ), the mandarin fish sample and a certified reference shrimp material (GBW10050) were extracted and determined with the previous method 26 .…”

“…Each species of Pb in fish, shellfish and shrimp samples was determined by CE-ICP-MS with the method reported in our previous paper 26 . In summary, firstly, inorganic lead (Pb 2+ ) and organolead lead including TML and TEL in dried sea foods was separately extracted with a microwave-assisted extraction method by using 50% methanol solution (dissolved in 70 mmol/L H 3 BO 3 –17.5 mmol/L Na 2 B 4 O 7 solution) and 0.5M acetic acid as solvent respectively.…”

“…For example, high performance liquid chromatography (HPLC) and gas chromatography (GC) coupled with atomic emission spectrometry (AES) 19 , mass spectrometry and inductively coupled plasma mass spectrometry (ICP–MS) 20 21 22 23 24 25 . Not long ago, we developed a environment-friendly microwave-assisted extraction method for quantitatively extracting trace lead compounds from sea foods without altering the individual lead species, and we also developed a sensitive method for simultaneously determining Pb 2+ , trimethyl lead (TML) and triethyl lead (TEL) in sea foods with CE-ICP-MS 26 . The previous research provided a realistic approach for investigating the species characteristic of Pb in sea foods.…”

Recent advances in CE‐MS coupling: Instrumentation, methodology, and applications

“…A commercial instrumentation for CE‐ICP‐MS coupling is available. Fu's lab used the CE‐ICP‐MS system with CEi‐SP20 CE‐interface (Reeko Instrument, Xiamen, China) and an Agilent 7700 ICP‐MS (Agilent Technologies, USA) for analysis of heavy metals in food and water . They developed various concentration methods.…”

“…CE methods were developed for contactless conductivity, fluorescence, UV, and MS detection. The authors declare the systems with contactless conductivity and fluorescence detection superior to UV and MS. As already mentioned, CE‐ICP‐MS was used for the speciation of trace amounts of lead in marine animals , chromium in a nutritional supplement , arsenic in rice , and ultratrace amounts of mercury in water samples . Acunha et al.…”