합성수지 포장재중 Solid Phase Microextraction법을 이용한 Acrylonitrile 분석법 확립

Abstract

우리나라 식품 공전에는 acrylonitrile styrene과 acrylonitrile butadiene styrene 수지로 만들어진 식품 용기,기구 및 포장의 acrylonitrile용출규격은 0.02mg/L 이하로 규정하고 있다.그러나 식품공전에 수록된 실험방법은 GC-NPD의 검출한계 때문에 용출규격이하를 검출 할 수가 없다. 그래서 acrylonitrile의 분석 감도가 좋은 방법과 기기 조건을 정립하여 acrylonitrile계 합성수지제에서 acrylonitrile이행량 모니터링 및 확산 계수를 산출하기로 하였다.분석법 개발을 위해 증류농축시키는 증류법,purge& trap 및 SPME를 이용한 정량한계,검출한계를 비교하였다.0.2ng/ml의 정량한계와 0.06ng/ml의 검출한계를 나타낸 SPME법이 다른 전처리법들보다 우수하게 나타났다.그래서 SPME 최적화 조건 분석을 위해 5가지 종류의 fiber를 사용하였다.사용된 fiber로는 75㎛ carboxen/polydimethylsiloxan(Carboxen/PDMS),50/30㎛ divinylbenzene/carboxen(DVB/Carboxen),85㎛ polyacrylate(PA),100㎛ polydimethylsiloxane(PDMS),65㎛ polydimethylsiloxane/divinylbenzene(PDMS/DVB)이다.이리하여 5종류의 fiber중 가장 효율적인 fiber를 이용하여 최적의 흡착 온도와 시간을 알아 보았다. 최적의 SPME 분석조건은 75㎛ Carboxen/PDMS fiber를 이용하여 acrylonitrile을 흡착시키는 최적의 조건인 노출 온도 및 노출시간은 40℃,30분으로 나타났다.75㎛ Carboxen/PDMS fiber를 이용한 다른 조건들은 내부표준물질로 propionitrile을 사용하며 50℃ 수욕조 안에 10mlheadspacevial을 넣어 vial안의 5ml시료용액을 안정화를 시키는 것이다.시료용액은 SPME로 흡착시키기 전 이온세기를 조절하기 위해 NaCl을 시료용액에 35%(W/V)가 되게 첨가하여 만든다. Acrylonitrilestyrene수지 30건,acrylonitrilebutadienestyrene 수지 20건과 elastomer 4종을 수거한 후 확립된 SPME법을 사용하여 증류수로의 acrylonitrile 이행량을 분석하였다.가장 높은 acrylonitrile의 검출치로는 acrylonitrilebutadienestyrene수지에서 검출된 19.68ng/ml로 식품공전의 용출규격인 20ng/ml이하와 거의 비슷한 수준이다. Fick's의 법칙을 기반으로 한 확산모델로 60℃에서 acrylonitrile의 확산계수를 산출하였다.증류수로의 acrylonitrilestyrene수지로부터 이행된 acrylonitrile은 0.03064㎟/h확산계수 값을 나타내었다.

Acrylonitrile is regulated by the Korean Food Code that its eluted amount should not be more than 0.02 mg/L into food simulant from acrylonitrile-styrene and acrylonitrile- styrene-butadiene. However, the analytical method for acrylonitrile in the Korean Food Code could not detect the permissible elution limit due to a detection limit of GC-NPD. Therefore, the objectives of this study were to develop a sensitive analysis method and instrument conditions for the acrylonitrile in aqueous food simulant, to monitor the acrylonitrile in food packages distributed in markets using the established method, and to determine the diffusion coefficients of acrylonitrile from food package into distilled water. To develop the sensitive analysis method for acrylonitrile, concentration treatment, purge & trap and solid phase microextraction (SPME) were compared with quantitation limit and detection limit. SPME, shown in 0.2 ng/ml of quantitation limit and 0.06 ng/ml of detection limit, was superior to the other methods. So, in order to optimize the condition of SPME treatment, five fused silica fibers were evaluated for the performance, which were coated with 75㎛ carboxen/polydimethylsiloxane (CAR/PDMS), 50/30㎛ divinylbenzene/Carboxenon polydimethylsiloxane (DVB/CAR), 85㎛ polyacrylate(PA), 100㎛ polydimethylsiloxane (PDMS) and 65㎛ polydimethylsiloxane/divinylbenzene (PDMS/DVB), respectively. Then, optimum absorption temperature and time were studied for the most efficient fiber in the five fibers. The optimized SPME method is 75㎛ CAR/PDMS fiber at 40℃ for 30min. The other absorption condition of 75㎛ CAR/PDMS fiber for acrylonitrile isolation was propionitrile as an internal standard and 5㎖ sample solution in 10㎖ head space vial at 50℃ of a water bath in which the sample solution was stirred magnetically. The sample solution was made into 35%(w/v) NaCl to control ionic strength before the absorption with SPME. The 30 kinds of acrylonitrile-styrene containers, 20 kinds of acrylonitrile- butadiene-styrene containers and 4 kinds of elastomers were analyzed to measure the migrated acrylonitrile content into the distilled water using the established SPME method. The highest concentration of migrated acrylonitrile was 19.68 ng/ml in a acrylonitrile-butadiene-styrene container, which is very close to 20 ng/ml of the accepted level in the regulation of the Korea Food Code. Diffusion model based on Fick's law was used to determine the diffusion coefficient of the acrylonitrile at 60℃. Specific migration of acrylonitrile from acrylonitrile-styrene into distilled water showed the diffusion coefficient of 0.03064 ㎟/h, showing the good corelation for the diffusion model. The newly developed and optimized SPME condition can apply to isolate acrylonitrile from several acrylonitrile-related containers into food simulant for regulating containers.