Rapid Determination Of Aluminum Element In Fried Food

The aluminum is a metal element with low accumulative toxicity. The mainly source of aluminum in food samples is raising agent that is mixed in the producing process and the contact with aluminum appliance in the storing process. When this kinds of food are ingested by human and accumulated in the body, it will have great harmful for each organization organ, the nervous system and the skeleton of human body. Varied methods in the domestic and foreign have been developed for determination of aluminum(III) in food samples, such as spectrophotometry, inductively coupled plasma mass spectrometry, atomic absorption spectrometry, etcetera.The spectrophotometry is a technique with various important advantages, such as simple, easy and rapid. The solid-phase spectrophotometry(SPS) is a rapidly developed methed in analysis of aluminumin(III) in food samples in recent years, and attracted extensive attention, it can provide a new thought.A new chromogenic agent for the determination of trace amounts of aluminum in the food samples by spectrophotometric analysis methed is described in this paper. The reaction condition of solution-phase spectrophotometry was optimized, the result indicated:in pH5.5170g/L ethanoic acid-sodium acetate buffer solution, aluminum was combined with0.1%(w/v)shilvling chromogenic agent as a aluminum-shilvling complex in the room temperature for20min, the complex have a biggest absorption peak at598nm, an apparent molar absorptivity of2.6×104L/mol·cm, minimum detectability of8.9μg/L, the quantification limit of1μg/mL, the relatively standard deviation of2.9%. The tolerance limit of coexistent ions was also investigated, most of them are in tolerable amount, the thiourea, the used of antiscorbutic acid, acetylacetone and triethanolamine can eliminate the interferences caused by Cu2+,Fe3+,Cr2+.This experiment has also completed the contrast research of the solid phase adsorption material and choosed hydrophilic microporous filtering film as the most suitable solid-phase adsorption material, Then the colored condition was optimized. The results indicated that the membrane has the bright colored difference when the volume of aluminum-ethanoic acid-sodium acetate is10mL and the density scopes of aluminum is0～4μg/mL. Reference color card of aluminum can be prepared under optimum conditions.The aluminum content in13kinds of food were determinated. The determination results compares with inductively coupled plasma mass spectrometry. Food samples were spiked with three levels of25μg/g,50ug/g,100μg/g. Good recovery of these samples was achieved ranging from90.65%to104.95%.