2,4,6-三(2′-吡啶基)-1,3,5-三嗪作显色剂分光光度法测定手面皮肤的铁含量

Spectrophotometric Determination of Iron on Skin of Hand Palm with 2,4,6-(2′-Pyridyl)-1,3,5-Triazine as Chromogenic Reagent

应用铁(Ⅱ)与2,4,6-三(2′-吡啶基)-1,3,5-三嗪(TPTZ)的显色反应,用分光光度法测定了手表面皮肤上沾染铁的含量。测定时,用在去离子水中浸湿的脱脂棉擦拭手皮肤上铁的印迹,将脱脂棉中的液体挤出并接盛于小烧杯中,重复操作一次。将两次擦拭所得液体移入25mL容量瓶中,加入30g·L-1抗坏血酸溶液2mL,1g·L-1 TPTZ溶液2mL及pH 4.2乙酸铵缓冲溶液3mL,加水至刻度,在室温下放置10min。测定波长为596nm,按此条件,铁(Ⅱ)的质量浓度在2.0mg·L-1以内遵守比耳定律。试验结果表明:手与铁器接触时间长,则沾染在手面的铁量多;手面的湿度越高,沾染的铁量也越多,其最大值和最小值之间相差可达12μg。

Based on the color reaction of Fe(Ⅱ)with 2,4,6-(2′-pyridyl)-1,3,5-triazine(TPTZ)as chromogenic reagent,a spectrophotometric method for determination of iron contaminated on skin of hand palm was proposed.Imprint of iron ware on the palm skin was collected by wiping with absorbent cotton wetted previously in deionized water,and the liquid contained in the cotton was squeezed out and recieved into a 25mL volumetric flask.The collection was repeated once more.The color reaction was carried out by addition of 30g·L-1 ascorbic acid solution(2mL),1g·L-1 TPTZ solution(2mL)and pH 4.2NH4OAc buffer solution(3mL)in succession.After diluting to 25mL and standing for 10min,its absorbance was measured at 596nm.Beer′s law was obeyed in the range within 2.0mg·L-1.It was shown that upon grasping iron ware in one′s palm,amount of iron on the palm skin increases with the increase of grasping time,and higher the humidity of palm skin,higher will be the amount of iron contaminated.A difference of 12μg of iron was found between the maximum and mininum values.