| As the balance ion of other cation, chloride played an important part inthe osmotic pressure of the body. It was widely distributed in the body’ excitable andnon-excitable cells membrane, and also in the plasma membrane of organelles, suchas lysosomal and mitochondria and endoplasmic reticulum. It had an important rule inthe regulating cell excitability, up the leather material transport and cell volumeregulating organelle acidification. But the excessive chloride ion would cause damageto the body, for example: severe dehydration, reduced defence capability, bone growthdisorder and so on. Continued to excessive intake of chloride could cause clinicalillness such as the ureter-intestinal anastomosis, renal failure, the urine solute load toomuch, diabetes insipidus and enhanced absorption of chlorine and so on. All abovecould cause chlorine excessive hyperchoremia. In addition, sensitive individuals couldalso lead to high blood pressure.Borax had antiseptic effect, it could increase food strength and water retention,but it was ighly toxic, adult once ingested1-3g would be poisoned, and15g wouldcause death. Continuous intake would cause the accumulation of poisoning. Stateclearly defined borax is disabled food additives, but part of producers still used it inthe processing in order to improve the appearance and the flexibility. Because of theGB had non of borax quantitative detection, the rapid determination of food borax hadthe positive and realistic significance to the maintenance of food secueity andprotection of human health.Copper was the body’ active ingredient of the30kinds of enzymes. Itparticipated in the growth hormone, the pituitary hormone, and other important lifeactivities. As the body’essential trace elements, it could promote iron absorption in thegastrointestinal tract, mature red blood cells, keep the elasticity of blood vessels andbones tenacity and regulating cardiac. Copper deficiency could cause mentalstagnation, movement disorders and overall malnutrition. Although copper wasimportant, excessive intake was not good. In the GB, provision of the copper content in the food could not be more than10mg/kg. However, the dangers of excess copperin the body depended not only on how much of the total, also related to the differentkinds of dissolution characteristics. So the determination of the different kinds ofdissolution characteristics of copper in food would conducive to refine the mechanismof copper poisoning, which had some practical significance.This study selected pickles, yuba and tea as the research material for the abovethree substances. The research was on the chloride and the borax and the differentchemical speciations of copper by direct-reading method of concentration. The resultswere as follows:1. It provided a simple and quick determination method for the chloride. Withpickles for samples and super living wave auxiliary treatment, the experiment usedthe direct-reading method of concentration with chloride ion selective electrode. Theresults show that: when the pH of the total ionic strength adjust buffer（TISAB） was5.50, the Sodium Citrate recruitment was0.20g/L, and the potassium nitrateconcentrations was0.80mol/L, the recovery was94.1105.6%,the RSD（n=5） wasunder3%, the detection limit was1.20×10-5mol/L. This method need no mapping, andis very cheap, simple quickly, selective and readings intuitive method for field testing.2. It provided a rapid determination method for the borax. With yuba for samples,borax became to fluoroborate ion through acidification and fluoride treatment, thisexperiment adopt the direct-reading concentration with fluoroborate ion selectiveelectrode by fixed time method. The results show that: It need1.00mL sulfuric acidwhen the concentration was1mol/L and4.00mL hydrofluoric acid when theconcentration was4mol/L， the RSD（n=11） was0.076%,the recovery was93.04%104.2%, the detection limit was1.12×10-5mol/L. This method is very cheap,need no mapping, simple quickly, selective and readings intuitive method for fieldtesting.3. It provided a determination method for the different kinds of dissolutioncharacteristics of copper. With tea for sample, copper became different kinds ofdissolution characteristics after water-soluble and alcohol-soluble and digestion. Theexperiment used the direct-reading concentration after standard solution addition withcopper ion selective electrode. The results show that: In the total ionic strengthadjustment buffer, the concentration of1.00mol/L of potassium nitrate solution usedin an amount of5.00ml, the concentration of1.00mol/L of fluoride solution used in anamount of5.00ml, and the pH was4.00. The relative standard deviation of tea samples was7.6%（n=11）, the recovery was92.25%～106.9%，and the detection limitwas1.13×10-5mol/L.This experiment provided a method of diect-reading concentration to detect thechloride in pickles and the borax in yuba and the different dissolution properties ofcopper in tea, it not only gived us a inspection techniques of toxic and hazardous infood, but also appeared thinking of detecting the chemical speciation of heavy metal,so it offered an effective method to ensure food safety. |
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