• 한국환경농학회지
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• 제39권1호
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• pp.44-49
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• 2020

BACKGROUND: Benzo(a)pyrene is a highly toxic substance which has been listed as a Group I carcinogen by the International Agency for Research on Cancer. There have been numerous studies by researchers worldwide on benzo(a)pyrene. Soxhlet, ultrasound-assisted, and liquid-liquid extractions have been widely used for the analysis of benzo(a)pyrene. However these extraction methods have significant drawbacks, such as long extraction time and large amount of solvent usage. To overcome these disadvantages, we aimed to establish a rapid residual analysis of benzo(a)pyrene content in agricultural products and soil samples. METHODS AND RESULTS: A Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was used as the pretreatment procedure. For rapid residual analysis of benzo(a)pyrene, a modified QuEChERS method were used, and the best codition was demonstrated after various performing instrument analysis. The extraction efficiency of this method was also compared with Soxhlet extraction, the current benzo(a)pyrene extracting method. Although both methods showed high recovery rates, the rapid residual analysis method markedly reduced both the measurement time and solvent usage by approximately 97% and 96%, respectively. CONCLUSION: Based on these results, we suggest the rapid residual analysis method established through this study, faster and more efficient analysis of residual benzo(a)pyrene in major agricultural products such as rice, green and red chili peppers and also soil samples.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.3107-3110
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• 2014

• Parasites, Hosts and Diseases
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• 제47권3호
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• pp.227-233
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• 2009

Local malaria transmission in the United Arab Emirates (UAE) came to an end in 1997. Nevertheless, UAE has been subjected to substantial importation of malaria cases from abroad, concerning both UAE nationals and immigrants from malarious countries with a total number of 2,119 cases in 2007. To evaluate a new DNA extraction technique using nested PCR, blood samples were collected from 132 individuals who presented to Infectious Diseases Department in Rashid Hospital, Dubai, and Central Department of Malaria Control with fever and persistent headache. Giemsa-stained blood films and ELISA test for malaria antibodies were carried out for detection of Plasmodium infection. Plasmodium infections were identified with the genus-specific primer set and species differentiation using nested PCR. A rapid procedure for diagnosis of malaria infections directly from dried blood spots using for the first time DNA extract from FTA Elute cards was evaluated in contrast to extraction techniques using FTA classic cards and rapid boiling technique. Our new simple technique for DNA extraction using FTA Elute cards was very sensitive giving a sensitivity of 100% compared to 94% using FTA classic cards and 62% in the rapid boiling technique. No complex preparation of blood samples was required prior to the amplification. The production cost of DNA isolation in our PCR assay was much less incomparable to that of other DNA extraction protocols. The nested PCR detected plasmodial infection and could differentiate P. falciparum from P. vivax, and also detected the mixed infection.

• 생약학회지
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• 제52권3호
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• pp.157-162
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• 2021

The heat-mediated reflux apparatus extraction of Paeonia lactiflora Pall. has been widely used as a traditional extraction method. In this paper, the microwave apparatus extraction method of Paeonia Radix was performed and the active ingredients and functional constituents were compared with the reference extraction method. The most effective extraction condition of albiflorin using the microwave was 120℃ in 50% methanol, and paeoniflorin was maximally extracted at 60℃. The reduced level of paeoniflorin molecule at high-pressure and high-temperature extraction condition was caused by the molecular instability. Additionally, the microwave extraction of 50% methanol extracts at 150℃ showed the highest functional constituents determined by in vitro DPPH radical scavenging activity, polyphenol concentration, and tyrosinase inhibition assay. The microwave apparatus was adapted as a rapid, low-cost, and environmentally friendly method to extract active ingredients and the practical extraction conditions of Paeonia Radix can be used in industrial applications.

• 한국식품과학회지
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• 제29권6호
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• pp.1327-1329
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• 1997

인삼으로부터 사포닌 화합물의 신속한 추출방법을 모색하기 위하여 waring blonder 와 유기용매를 이용한 새로운 추출방법을 개발하였다. 본 방법은 기존의 인삼 증류추출방법과 비교해볼 때 6개의 주종 사포닌($ginsenoside-Rb_2$, $ginsenoside-Rb_1$, ginsenoside-Rc, ginsenoside-Rd, ginsenoside-Re, $ginsenoside-Rg_1$) 함량이 유사하여 유의성이 있는 것으로 생각된다. 유기용매는 메탄올과 클로로포름을 7:3의 비율로 사용하였을 때 사포닌 화합물이 잘 추출되었다. 5개의 주종사포닌을 합한 전체 사포닌 함량은 본 방법에서는 2.41% 이었고 기존의 방법 에서는 2.54%이었다. 그러나 조사포닌의 함량은 본 방법이 기존의 방법보다 높은 것으로 나타났다.

• 대한소아치과학회지
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• 제34권3호
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• pp.498-505
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• 2007

매복치의 치료는 발생 원인, 치아 발육 상태, 매복 위치 및 맹출 경로, 맹출 공간 여부, 환자의 연령이나 협조도 등을 고려하여 시행하며 방해 요인 제거 후 자연 맹출 관찰, 매복치의 외과적 노출 후 교정적 견인, 매복치의 재위치 또는 치아이식, 발거 후 보철수복을 할 수 있다. 이 중 치아이식은 매복치가 맹출 경로를 크게 벗어나 외과적인 노출과 교정적 견인이 어려운 경우 시행할 수 있다. 자가치아이식의 성공을 위해 이식치아의 외상을 최소화하며 치주인대의 생활력을 보존하는 것이 중요하다. 본 증례에서는 상악 좌측 견치의 미맹출을 주소로 내원한 10세 여자 환자에서 Rapid Prototyping model을 이용하여 자가치아이식술을 시행하였다. RP technique을 이용하여 제작한 공여치의 모델로 수용부의 골와동 형성을 공여치 발치전에 미리 시행함으로써 공여치의 구강 외 소요시간을 단축시키고 공여치를 수용부에 여러 번 시적할 때 생길 수 있는 치근 손상을 최소화할 수 있었다. 치료 후 상악 좌측 견치는 6개월 후 치근 흡수 등의 합병증 없이 정상 치아 동요도와 타진시 음성을 나타내었으며 전기치수검사에서 양성 반응을 보였다.

• 한국동물위생학회지
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• 제29권3호
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• pp.339-346
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• 2006

Semi-micro-HPLC using a column-switching technique was developed for simultaneous determination of vitamin A and E contents in infant formula. Vitamin A and E were extracted by PDA - HPLC with reversed phase column using organic solvent and their contents in Certified Reference Material (CRM) and infant formula were determined and compared with hydrolysis method and rapid extraction. Developed method has many advantages of simple and rapid sample preparation and simultaneous determination of vitamin A and E by micro-HPLC using reversed phase column.

• Bulletin of the Korean Chemical Society
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• 제25권4호
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• pp.545-548
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• 2004

A sensitive, selective and rapid method for the determination of nickel based on the rapid reaction of nickel(II) with QADMAA and the solid phase extraction of the Ni(II)-QADMAA chelate with $C_{18}$ membrane disks has been developed. In the presence of pH 6.0 buffer solution and sodium dodecyl sulfonate (SDS) medium, QADMAA reacts with nickel to form a violet complex of a molar ratio of 1 : 2 (nickel to QADMAA). This chelate was enriched by solid phase extraction with $C_{18}$ membrane disks. An enrichment factor of 50 was obtained by elution of the chelates form the disks with the minimal amount of isopentyl alcohol. The molar absorptivity of the chelate was $1.32{\times}10^5L\;mol^{-1}cm^{- 1}$ at 590 nm in the measured solution. Beer's law was obeyed in the range of 0.01-0.6 ${\mu}$g/mL. This method was applied to the determination of nickel in water and biological samples with good results.

• Bulletin of the Korean Chemical Society
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• 제25권4호
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• pp.549-552
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• 2004

A sensitive, selective and rapid method has been developed for the determination of mercury based on the rapid reaction of mercury(II) with p-sulfobenzylidenethiorhodanine (SBDTR) and the solid phase extraction of the colored chelate with $C_{18}$ disks. In the presence of pH 3.5 sodium acetate-acetic acid buffer solution and Emulsifier-OP medium, SBDTR reacts with mercury(II) to form a red chelate of a molar ratio 1 : 2 (mercury to SBDTR). This chelate was prconcentrated by solid phase extraction with $C_{18}$ disks. An enrichment factor of 50 was achieved. The molar absorptivity of the chelate is $1.28{\times}10^5 L{\cdot}mol^{-1}{\cdot}cm^{-1}$ at 545 nm in measured solution. Beer's law is obeyed in the range of 0.01-3 ${\mu}$g/mL. The relative standard deviation for eleven replicates sample of 0.01 ${\mu}$g/mL is 1.65%. This method was applied to the determination of mercury in tobacco and tobacco additive with good results.

• Bulletin of the Korean Chemical Society
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• 제25권2호
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• pp.263-266
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• 2004

A sensitive, selective and rapid method has been developed for the determination ${\mu}$g/L level of vanadium ion based on the rapid reaction of vanadium(V) with 2-(2-quinolylazo)-5-diethylaminophenol (QADEAP) and the solid phase extraction of the colored chelate with $C_{18}$ cartridge. The QADEAP reacts with V(V) in the presence of citric acid-sodium hydroxide buffer solution (pH = 3.5) and cetyl trimethylammonium bromide (CTMAB) medium to form a violet chelate of a molar ratio 1 : 2 (V(V) to QADEAP). This chelate was enriched by solid phase extraction with $C_{18}$cartridge and the enrichment factor of 50 was obtained by elution of the chelates from the cartridge with ethanol. The molar absorptivity of the chelate is $1.28 {\times}10^5L\;mol^{-1}cm^{-1}$ at 590 nm in the measured solution. Beer's law is obeyed in the range of 0.01-0.6 ${\mu}$g/mL. The detection limit is 0.04 ${\mu}$g/L in the original samples. This method was applied to the determination of vanadium(V) in water and biological samples with good results.