Development of A High Throughput Rapid Detection Method for Sodium Thiocyanate in Pure Milk

Based on the principle of reaction of thiocyanate and ferric iron ions to form blood red complex,a high throughput rapid detection method for sodium thiocyanate in pure milk was developed by using microporus plate as color carrier through the steps of screening of color reagent,optimization of color condition and performance evaluation. Microporous plate was chosen for color developing carrier. The working conditions of this method were as follows:1.5 mol/L iron perchlorate solution(dissolved with 2.0 mol/L perchloric acid solution)served as chromogenic agent,reacting 5 min at 25℃,absorption values at 465 nm were recorded. The results showed that the limit of detection of this method was 0.27 mg/kg,the limit of quantification was 0.90 mg/kg,the linear range was 0.90~80.00 mg/kg,the addition recovery range was 83.9%~98.6%,and the relative standard deviation(RSD)of repeated tests was less than 10.0%. This method has the advantages of high accuracy and throughput,small amount of reagent,environment friendly,rapid,etc.,and is suitable for rapid screening of sodium thiocyanate residue for large quantities of pure milk samples.