Determination of sudan dyes in red wine and fruit juice using ionic liquid‐based liquid–liquid microextraction and high‐performance liquid chromatography

Abstract

The liquid-liquid microextraction (LLME) was developed for extracting sudan dyes from red wine and fruit juice. Room temperature ionic liquid was used as the extraction solvent. The target analytes were determined by high-performance liquid chromatography. The extraction parameters were optimized. The optimal conditions are as follows: volume of [C(6)MIM][PF(6)] 50 μL; the extraction time 10 min; pH value of the sample solution 7.0; NaCl concentration in sample solution 5%. The extraction recoveries for the analytes in red wine and fruit samples are 86.79-108.28 and 68.54-85.66%, whereas RSDs are 1.42-5.12 and 1.43-6.19%, respectively. The limits of detection and quantification were 0.428 and 1.426 ng/mL for sudan I, 0.938 and 3.127 ng/mL for sudan II, 1.334 and 4.445 ng/mL for sudan III, 1.454 and 4.846 ng/mL for sudan IV, respectively. Compared with conventional liquid-liquid extraction (CLLE) and ultrasonic extraction (UE), when LLME was applied, the sample amount was less (LLME: 4 mL; CLLE: 10 mL; UE: 10 mL), the extraction time was shorter (LLME: 15 min; CLLE: 110 min; UE: 50 min) and the extraction solvent amount was less (LLME: 0.05 mL IL; CLLE: 15 mL hexane; UE: 20 mL hexane). The proposed method offers a simple, rapid and efficient sample preparation for determining sudan dyes in red wine and fruit juice samples.

New approach applying a pet fish air pump in liquid‐phase microextraction for the determination of Sudan dyes in food samples by HPLC

“…These data are in agreement with the literature . These results are obtained because all four dyes exist as neutral molecules under ordinary conditions and do not undergo noticeable dissociation or protonation in moderately acidic or basic media .…”

Determination of Sudan Dyes in Juice Samples via Solidification of Ionic Liquid in Microwave-Assisted Liquid-Liquid Microextraction Followed by High-Performance Liquid Chromatography

“…In order to evaluate the performances, some other methods reported in the literature, including dispersive liquid-liquid microextraction (DLLME) (Sun et al 2011;Zhou et al 2014), aqueous two-phase systems extraction (ATPSE) (Yu et al 2015), magnetic solid-phase extraction (MSPE) , were compared with the present method for Sudan dye extraction, and the results are shown in Table 6. From the table, the proposed method showed superiority over others in respect of extraction time and the amount of organic solvent with acceptable recoveries and detection limits.…”

“…The injection volume of analytical solution was 20 μL. The monitored wavelengths were 478 nm for Sudan I and Sudan II, 520 nm for Sudan III and Sudan IV (Sun et al 2011). …”

“…To examine the influence of ionic strength on the extraction efficiency, we compared sodium sulfate with sodium chloride in the experiment; the effects were similar. Sodium chloride was chosen due to it dissolved in water easily (Sun et al 2011). A series of experiments were performed by adding different amounts of sodium chloride (0-11 %, w/v).…”

Inedible Azo Dyes and Their Analytical Methods in Foodstuffs and Beverages

“…The traditional solvent extraction has the defects of requiring a large amount of hazardous organic solvents and much time consumption. Therefore, new techniques based on the traditional solvent extraction with modifications or improvements have been developed and applied in the analysis of the inedible azo dyes, such as liquid-liquid microextraction and automatic online liquid-liquid extraction (40).…”