稀土与四环素类抗生素络合物的光度法研究

Studies on Complexes of Rare Earth Elements with Tetracycline Antibiotics by Spectrophotometry

在pH 7～ 8的弱碱性介质中 ,稀土元素与四环素 (TC)、强力霉素 (DOTC)、土霉素 (OTC)及金霉素(CTC)反应形成浅黄色络合物 ,La 与不同抗生素的反应产物最大吸收位于为 388～ 394nm ,Y 与不同抗生素的反应产物最大吸收位于 388～ 398nm。用于四环素类抗生素的光度测定 ,以La 测定时 ,其线性范围在 0～ 9.0mg L至 0～ 14.0mg L之间 ,ε值在 1.49× 10 4～ 2 .2 9× 10 4L·mol- 1 ·cm- 1 之间 ;当用Y 测定时 ,线性范围在 0～ 10 .0mg L至 0～ 11.0mg L之间 ,ε值在 1.5 3× 10 4～ 2 .47× 10 4L·mol- 1 ·cm- 1 之间。方法用于市售药物中有关抗生素含量测定 ,结果满意。

In pH 7 similar to 8 weak basic medium, rare earth elements react with tetracycline(TC), doxycycline(DOTC), oxyteracycline(OTC), and chlortetracycline(CTC) to form light yellow complexes. La(III) and Y(III) were studied as examples, the maximum absorption peaks of reaction products produced by the reactions of La(III), Y(III) and different antibiotics were located between 388 similar to 394 nm and 388 similar to 398 nm respectively. They can be applied to the photometric determination of antibiotics such as tetracycline. When La(III) was used for determination, the linear ranges were between 0 similar to 9.0 mg/L to 0 similar to 14.0 mg/L. The molar absorptivities were between 1.49 x 10(4) and 2.29 x 10(4) L.mol(-1).cm(-1). When Y(III) was used to the determination, the linear ranges were between 0 similar to 10.0 mg/L to 0 similar to 11.0 mg/L, and molar absorptivities were between 1.53 x 10(4) and 2.47 x 10(4) L.mol(-1).cm(-1). The method was applied to the determination of antibiotics and satisfactory results were obtained.