静电纺丝法制备水中氨氮快速检测试纸

Preparation of test paper for rapid determination of ammoniacal nitrogen in water by electrostatic spinning method

利用静电纺丝法制备了纳米聚乳酸-乙醇酸膜作为氨氮快速检测试纸的纸基,采用国标GB7479-87水中氨氮测定标准的纳氏试剂显色法原理制成试纸并对试纸的制备条件和显色条件进行了研究.通过扫描电子显微镜、红外光谱仪进行了表征.扫描电镜观察材料的微观结构表明,PLGA静电纺丝材料纤维直径在纳米级别,其表面光滑,粗细较均匀,交织成网状.所制得的试纸氨氮检测限为0~50mg/L;浸渍液的最佳配比为1.5g氨试剂加入20mL无氨水,滴加2滴620g/L的氢氧化钾溶液;其中氨试剂（碘化钾∶碘化汞∶酒石酸钾钠∶氯化钠）的配比为0.5∶1∶0.5∶30;检测实体水样时,试纸显色深浅随氨氮浓度由低至高呈明显梯度加深,色阶明显.试纸的检测结果与国标法测定结果吻合度高,并且数据重现性好.

In this study,polylactic acid-glycolic acid（PLGA）was prepared by electrostatic spinning method,which acts as the paper base of test paper for rapid determination of ammonia nitrogen.The test papers were prepared by the method of national standard GB7479-87 ammonia nitrogen in the water and the conditions of preparation and coloration were studied.In the same time,the preparatim condttions and chromogenic conditims of the test papers were studied.The microstructure of the material was observed by scanning electron microscopy（SEM）and infrared spectroscopy（IR）.The SEM results showed that the fiber diameter of nano-electrospun PLGA was smooth at the nanometer level,and the thickness was uniform and interwoven into a network.The system test ammonia detection limit is 0~50 mg/L;the best ratio of impregnation liquid is 1.5 g ammonia reagent with 20 mL ammonia free water and 2 drops 620 g/L potassium hydroxide solution.The ratio of ammonia reagent（potassium iodide∶mercuric iodide∶potassium sodium tartrate∶sodium chloride）is 0.5∶1∶0.5∶30.When we detected water samples,the color depth of test paper was obviously gradient increasing with the concentration of ammonia nitrogen from low to high concentration.The detected results of the test paper were in conformity with that of national standard method.Furthermore,the data has good reproducibility.