Development Of Salamo-Type Chemical Sensor And Its Application In The Detection Of Heavy Metal Ions,Anions And Amino Acids In Water Samples

At present,short water resources and metal pollution are two major problems in China's water resources.Heavy metal pollution water resources not only seriously affect the ecological environment,but also directly pollute the soil,causing heavy metal pollution of agricultural products and threatening human health.Nowadays,many agricultural products have been found to contain heavy metal elements,so developing a fast,accurate and efficient method for detecting heavy metal ions in complex water samples is the focus and hotspot of environmental science and biomedical research.Fluorescent sensor molecules are widely used in the field of ion detection because of their easy synthesis,high sensitivity and selectivity,fast response,and strong anti-interference ability.In this dissertation,four water-soluble salamo-type chemical sensors are designed and synthesized,and they have good recognition performance for specific ions and amino acids in aqueous systems and actual water samples,and systematically studied their recognition performance in aqueous systems and even in actual water samples.This dissertation is elaborated from the following aspects:1.The bis?salamo?-type chemical sensor D1 is synthesized by modifying the terminal group with 2-hydroxy-1-naphthaldehyde,and the Cu²⁺ion is detected.The experimental results show that the sensor D1 can detect Cu²⁺ions by fluorescence quenching in water.The advantage is that the sensor have a low detection limit,a high coordination constant?3.93×10⁸mol/L?,a wide pH range?3.0-8.0?,and a fast response time?about 10 seconds?for Cu²⁺ion.In addition,the test paper loaded with sensor D1 was prepared,and used to conveniently,quickly and accurately detect Cu²⁺ion in aqueous solution.Therefore,this kind of sensor has potential application values in the detection of Cu²⁺ions in real life.2.The second type of bis?salamo?-type chemical sensor D2 was synthesized by modifying the terminal group with vanillin.The Cu²⁺ion is first detected.The experimental results show that the sensor can detect Cu²⁺ions by fluorescence quenching in water.In comparison,we found that the sensor D2 has a higher binding capacity to Cu²⁺ions than the sensor D1,and the sensor D2 has a lower detection limit for Cu²⁺ions than D1.In addition,a test paper loaded with sensor D2 was also prepared,and can be used to conveniently,quickly and accurately detect the presence of Cu²⁺ion in aqueous solution.Therefore,such sensors have potential application value in the detection of Cu²⁺ion in real life.In addition,the sensor can continuously identify Al³⁺ions in the system,and realize the recognition effect of other trivalent metal ions on the interference of Al³⁺ion.3.The complex ions of[D1-Na]⁺are synthesized by the interaction of D1 and NaOH,which can be used as a chemical sensor D4 to identify B₄O₇^2-ion in a contained system.The advantage are that the sensor can has a low detection limit,a high coordination constant(5.56×10^-8 mol/L and 3.75×10⁹ mol/L),and a wide pH range?3.0-8.0?,fast response time?about 10 seconds?for B₄O₇^2-ion.According to the experimental results obtained,a test paper loaded with the sensor D4 was also prepared,and can be used to conveniently and quickly and accurately detect the presence of B₄O₇^2-ion in the aqueous solution.Therefore,this kind of sensor has important application values in the detection of B₄O₇^2-ion in real life.4.Another type of bis?salamo?-type sensor D5 was obtained by reacting2-dihydroxy-5-methyl-1,3-benzenedialdehydeasaprecursorwith2-aminooxyethaneoxynaphthylnaphthol.Similarly,the experiment of cation detection is designed for the sensor.The experimental results show that the sensor can identify the Cu²⁺ions in an aqueous system.The difference is that the sensor can not only effectively recognize Cu²⁺ion in water,but also continuously identify S^2-ion and amino acids in water,and have lower detection limit and higher binding constant for the three kinds of sensors.While detecting these three different types of ions and compounds,they are not interfered by other ions of the same class.The recognition results achieve high selectivity,fast detection speed and low detection limit.