Detection method of lead ion

Abstract

The invention discloses a detection method of lead ions. The detection method comprises the following steps: adding a chloroauric acid solution into a reaction container, stirring, heating, when the temperature is 100 to 108 DEG C, adding a sodium citrate solution into the reaction container, continuously stirring and heating, stopping the heating at a first moment, continuously stirring until thesolution is cooled to the room temperature, adding 1mL of 8 to 12 mmol / L polyoxyethylene dehydrosorbitol monoleate into 100mL of solution, stirring until the second moment, adding 7 to 9 mL of 10mmol / L dodecylphosphonic acid tetrahydrofuran solution, stirring until a third moment, then adding 28 to 32 mmol / L of N-(2-ethoxy) piperazine-N'-2-ethanesulfonic acid solution, adjusting the pH to be 7.1to 7.3, obtaining a dodecylphosphonic acid functionalized gold nano particle composite, placing the nano gold particle composite in distilled water at the temperature of 2 to 6 DEG C to form a detection solution, adding a sample of to-be-detected lead ions into the detection solution, stirring and uniformly mixing, standing for 3 to 5 minutes, detecting light absorbency by adopting an ultravioletvisible light spectrophotometer, and obtaining the concentration of the lead ions according to the light absorbancy.

Description

technical field [0001] The invention relates to the technical field of heavy metal detection, in particular to a method for detecting lead ions. Background technique [0002] Lead ion is one of the most toxic heavy metal ions known to be potentially harmful. Lead is widely used due to its excellent ductility, easy processing and corrosion resistance. Its main pollution sources are man-made sources: gasoline, lead batteries, primary lead smelting, industrial waste water and gas emissions and pigments, and natural sources: geological erosion, crustal movement, weathering, etc., which makes its pollution very serious. Lead ion is a kind of toxic persistent heavy metal ion, its main chemical characteristic is to form organometallic compound, chelate, organic ligand and participate in redox reaction and so on. Heavy metals react with electron donors in living organisms or in water, and this reaction is usually irreversible. These sustainable harmful substances can enter the hum...

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Problems solved by technology

This patent uses boron cluster compounds to directly generate nano-gold in situ. The synthesis steps are simple, the reaction conditions are mild, and Pb2+ can be detected through color changes. However, the detection limit of this patent is relatively high, reaching 60nmol / L, and the sensitivity is not enough. The detection time is still longer for samples spiked with lead ions

[0006] Patent Document 2 discloses a lead ion colorimetric detection probe and its application method. The aqueous solution of chloroauric acid and glutathione are mixed and stirred in an aqueous solution with a substance ratio of 6:1, and oxidized with 1M hydrogen Sodium solution Adjust the pH value of the mixed solution to 7.0, then add newly prepared sodium borohydride ice water solution 2mg / 1mL to the mixed solution and stir vigorously, the mixed solution continues to react for 12 hours under stirring conditions, centrifuge to remove unreacted substances Redispersion, the patent uses glutathione functionalized gold nanoparticles as the lead ion colorimetric detection probe to detect Pb2+, but the detection limit of this patent is relatively high, the detection limit reaches 100nmol / L, and the sensitivity is not enough. Add The detection time of lead ion samples is still long

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