• Bulletin of the Korean Chemical Society
• /
• 제30권10호
• /
• pp.2387-2392
• /
• 2009

A composite film of multi-walled carbon nanotube (MWCNT)/sol-gel-derived zinc oxide(ZnO)/Nafion has been utilized as an efficient immobilization matrix for the construction of a highly sensitive and stable tris(2,2'-bipyridyl) ruthenium(II) (Ru(${bpy)_3}^{2+})$ electrogenerated chemiluminescence (ECL) sensor. The electrochemical and ECL behaviors of Ru(${bpy)_3}^{2+})$ ion-exchanged into the composite film were strongly dependent upon the sol-gel preparation condition, the amount of MWCNT incorporated into the ZnO/Nafion composite film, and the buffer solution pH. The synergistic effect of MWCNTs and ZnO in the composite films increased not only the sensitivity but also the long-term stability of the ECL sensor. The present ECL sensor based on the MWCNT/ZnO/Nafion gave a linear response ($R^2$ = 0.999) for tripropylamine concentration from 500 nM to 1.0 mM with a remarkable detection limit (S/N = 3) of 15 nM. The present ECL sensor showed outstanding long-term stability (94% initial signal retained for 5 weeks). Since the present ECL sensor exhibits large response towards NADH, it could be applied as a transduction platform for the ECL biosensor in which the NADH is produced from the dehydrogenase-based enzymatic reaction in the presence of NA$D^+$ cofactor.

• 분석과학
• /
• 제21권1호
• /
• pp.20-24
• /
• 2008

본 연구에서는 lucigenin과 $H_2O_2$에 의한 화학발광을 이용하여 vitamin $P_1$을 정량하는 방법에 대하여 연구하였다. 분석의 최적 조건을 구하기 위해서 화학발광에 영향을 미치는 $H_2O_2$의 농도, pH 그리고 lucigenin의 농도를 조사하였다. 이러한 분석 최적조건의 검정곡선에서 직선성이 성립하는 범위는 $7.5{\times}10^{-6}$에서 $5.0{\times}10^{-4}mol/L$이었고, 검정곡선에서 직선성이 성립하는 농도구간에서 구한 검출한계는 $5.7{\times}10^{-7}mol/L$이었다. 최적 vitamin $P_1$의 농도인 $7.5{\times}10^{-5}mol/L$에서의 상대표준편차는 0.75%(n=10), 상관계수(S/N=3)는 0.9984이었다.

• 농업과학연구
• /
• 제46권3호
• /
• pp.549-557
• /
• 2019

Staphylococcal enterotoxin is a very common cause of food poisoning. Conventional detection methods for the toxin including enzyme-linked immunosorbent assays (ELISAs), chemiluminescence (ECL), and polymerase chain reaction (PCR) assays require a lot of time, efforts, and expert technicians. Lateral flow strip kits have shown great potential for the rapid detection of foodborne pathogens. The lateral flow strip kit is widely used in clinical settings because it is easy to use, fast, and cost effective. A typical lateral flow strip kit uses colloidal gold to generate a visual signal. However, the lateral flow strip kit based on colloidal gold has limited sensitivity to fulfill food safety regulation requirements. This study was performed to develop a rapid test kit for pathogenic staphylococcal enterotoxin B (SEB) in food samples. The rapid detection kit was fabricated based on a nitrocellulose lateral-flow strip. Cellulose nano beads and SEB antibodies were used as the tag and receptor, respectively, to improve the detection performance. Manually spotted SEB antibody and anti-rabbit antibody on the surface of the nitrocellulose membrane were used as test and control spots, respectively. The feasibility of the rapid test kit to detect SEB in samples was evaluated. The sensitivity of the kit was 10 ng/mL SEB spiked in PBS. Additionally, the rapid test kit could detect 1 ng/mL of SEB in chicken meat extract.

• Bulletin of the Korean Chemical Society
• /
• 제29권8호
• /
• pp.1525-1532
• /
• 2008

An instrument was developed for the simultaneous determination of gas- and aerosol-phase nitrous acid (HONO). Gaseous HONO (HONO(g)) was sampled by a diffusion scrubber and particulate nitrite ($NO_2\;^-$(p)) was collected by a particle growth chamber. The collected samples were analyzed in time-sharing manner, based on the peroxynitrite-induced luminol chemiluminescence. The automated system was found to be sensitive with 13 pptv of detection limit, fast with 4 min. of sampling frequency, and simple and affordable to construct and operate. The system was optimized by adjusting the experimental parameters. The system was applied to the field measurement of gas- and particle-phase HONO during the springtime of 2004 in Gwangju, South Korea. HONO(g) concentrations varied diurnally from 200 pptv around 3 P.M. to 800 pptv at 5 A.M. The variation of $NO_2\;^-$(p) was not significant with the maximum of 240 pptv at 11 P.M. and the minimum of 170 pptv at 4 P.M., not displaying distinct characteristics.

• 대한화학회지
• /
• 제43권5호
• /
• pp.517-521
• /
• 1999

가스연료 중의 부취제 농도를 기체 크로마토그래피법으로 분석하기 위해 황화합물에 대한 선택성, 직선성, 감도가 매우 우수한 황 화학광 검출기(SCD)를 이용하여 측정하였다. 그리고, 기존의 GC-SCD에 의한 황화합물 분석방법과는 달리 황화합물의 흡착으로 인한 반복성 및 재현성 문제를 해결하는 실험방법을 이용하였다. 이러한 방법에 의하여, 액화석유가스에 첨가하고 있는 황화이메틸, t-부틸메르캅탄, 황화에틸메틸에 대하여 얻은 검정 곡선은 직선성을 잘 보여주고 있다. 실제 시료 중 위의 세가지 황화합물에 대한 실험결과의 정밀성을 측정한 결과, 4일동안 각3회 반복실험하였을 때 높은 재현성을 보여주었고, 농도의 변동계수(coefficient of variation)가 3% 미만의 값을 나타내었다. 결과적으로, 본 연구에 의한 실험방법은 저유소 및 충전소의 액화석유가스 시료에 첨가된 황 함유 부취제의 농도를 신속, 정확하게 측정하는, 매우 정밀성이 높고 유용한 방법이다.

• Clinical and Experimental Reproductive Medicine
• /
• 제17권1호
• /
• pp.71-80
• /
• 1990

항정자항체를 검사할 수 있는 면역분석법개발을 위하여 immunoaffinity chromatography로 분리 정제한 정자표현항원을 microtiter plate에 고정화 시킨것과 효소와 화학발광체로 표지된 2차항체를 사용하여 ELISA법과 CIA법을 개발하고 이 방법의 이용 가능성을 검토하기 위하여 기존 방법인 Kibrick test법으로 임상소견이 다른 남성혈청을 분석 비교하여 다음과 같은 결과를 얻었다. 1. 인간정자 표면항원을 분리하기 위한 immunoaffinity column을 제작키 위하여 인간정자를 토끼에 주사하여 정자에 대한 항혈청을 생산하였으며 이를 Protein A-Sepharose column으로 분리 정제하여 CNBr activated Sepharose-4B에 coupling시켜 immunoaffinity column을 제작하였다. 이 column에 균질화된 정자를 반응시키고 SDS를 넣은 Tris-HCI buffer로 용출시켰을때 60KD정도의 분자량을 갖는 분획을 얻었다. 2. 분리 정제된 human IgG를 microtier plate에 농도를 달리하여 고정화 시키고 ELISA용 Goat anti-human IgG-HRP conjugate와 CIA용 Rabbit anti-human IgG-ABEI-H conjugate와 반응시켜 그 활성도를 측정하였던 바 농도에 따라 반응의 정도가 감소하였다. 3. ELISA법으로 양성혈청의 희석곡선을 작성하였을때 경사가 완만한 것과 급한 것의 두 종류의 경향을 띈 곡선으로 대별되었으며 완만한 경사를 나타내는 것에서 1:160 희석치에서 O.D가가 0.1이하를 음성, 0.1이상 0.2이하를 약양성(weak positive) 그리고 0.2이상을 양성으로 판별하였다. 4. ELISA, CIA 그리고 Kibrick test로 동일시료를 분석 비교하였던바 ELISA와 CIA는 거의 동일한 상관관계를 보였으나 Kibrick test와는 50% 수준만 일치함을 보였다.

• Asian Journal of Atmospheric Environment
• /
• 제7권2호
• /
• pp.105-113
• /
• 2013

We constructed and tested an airborne peroxyacetyl nitrate (PAN) monitoring system based on luminol chemiluminescence detection with fast gas chromatography. This system allowed for simultaneous measurement of PAN and nitrogen dioxide ($NO_2$) with a time resolution of <2 min. Actual sample masses within the fixed volume sample loop at various altitudes and temperatures were adjusted to standard atmosphere, using measured pressures and temperatures. The airborne PAN measurement system was evaluated during two field studies above the southern Korean Peninsula in August and October 2009. The detection limit based on the ISO approach was 0.035 ppbv PAN, well below the observed concentrations of 0.185-1.49 ppbv during these studies. Under these conditions, the PAN mixing ratios were positively correlated with $O_x$ ($O_x=O_3+NO_2$), with slopes varying between 0.014 and 0.033 and intercepts between 22.6 and 55.1 ppbv $O_x$. The intercepts corresponded roughly to background $O_x$ mixing ratios in central Europe; however, the slopes were above the range of slopes reported in other studies. We also enhanced the durability, safety, and ease of maintenance of the PAN monitoring system by redesigning the structure of the conventional luminol cell.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권22호
• /
• pp.9611-9614
• /
• 2014

Purpose: To investigate the clinical value in lung cancer of a combination of four serum tumor markers, haptoglobin (Hp), carcinoembryonic antigen (CEA), neuron specific enolase (NSE) as well as the cytokeratin 19 fragment (CYFRA21-1). Materials and Methods: Serum Hp (with immune-turbidimetric method), CEA, NSE, CYFRA21-1 (with chemiluminescence method) level were assessed in 193 patients with lung cancer, 87 patients with benign lung disease and 150 healthy controls. Differences of expression were compared among groups, and joint effects of these tumor markers for the diagnosis of lung cancer were analyzed. Results: Serum tumor marker levels in patients with lung cancer were obviously higher than those with benign lung disease and normal controls (p<0.01). The sensitivities of Hp, CEA, NSE and CYFRA21-1 were 43.5%, 40.9%, 23.3% and 41.5%, with specificities of 90.7%, 99.2%, 97.9% and 97.9%. Four tumor markers combined together could produce a positive detection rate of 85.0%, significantly higher than that of any single test. With squamous carcinomas, the positive detection rates with Hp and CYFRA21-1 were higher than that of other markers. In the adenocarcinoma case, the positive detection rate of CEA was higher than that of other markers. For small cell carcinomas, the positive detection rate of NSE was highest. The area under receiver operating characteristic curve ($AUC^{ROC}$) of Hp in squamous carcinoma (0.805) was higher than in adenocarcinoma (0.664) and small cell carcinoma (0.665). Conclusions: Hp can be used as a new serum tumor marker for lung cancer. Combination detection of Hp, CEA, NSE and CYFRA21-1 could significantly improve the sensitivity and specificity in diagnosis of lung cancer, and could be useful for pathological typing.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권9호
• /
• pp.3867-3870
• /
• 2015

Background: To explore whether combined detection of serum tumor markers (CEA, CA72-4, CA19-9 and TSGF) improve the sensitivity and accuracy in the diagnosis of gastric cancer (GC). Materials and Methods: An automatic chemiluminescence immune analyzer with matched kits were used to determine the levels of serum CEA, CA72-4, CA19-9 and TSGF in 45 patients with gastric cancer (GC group), 40 patients with gastric benign diseases (GBD group) hospitalized in the same period and 30 healthy people undergoing a physical examination. The values of those 4 tumor markers in the diagnosis of gastric cancer was analyzed. Results: The levels of serum CEA, CA72-4, CA19-9 and TSGF of the GC group were higher than those of the GBD group and healthy examined people and the differences were significant (P<0.001). The area under receiver operating characteristic (ROC) curves for single detection of CEA, CA72-4, CA19-9 and TSGF in the diagnosis of GC was 0.833, 0.805, 0.810 and 0.839, respectively. The optimal cutoff values for these 4 indices were 2.36 ng/mL, 3.06 U/mL, 5.72 U/mL and 60.7 U/mL, respectively. With combined detection of tumor markers, the diagnostic power of those 4 indices was best, with an area under the ROC curve of 0.913 (95%CI 0.866~0.985), a sensitivity of 88.9% and a diagnostic accuracy of 90.4%. Conclusions: Combined detection of serum CEA, CA72-4, CA19-9 and TSGF increases the sensitivity and accuracy in diagnosis of GC, so it can be regarded as the important means for early diagnosis.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권15호
• /
• pp.6081-6086
• /
• 2014

Background: To evaluate the effectiveness of Microlux/DL with and without toluidine blue in screening of potentially malignant and malignant oral lesions. Materials and Methods: In this diagnostic clinical trial clinical examination was carried out by two teams: 1) two oral medicine consultants, and 2) two general dentists. Participants were randomly and blindly allocated for each examining team. A total of 599 tobacco users were assessed through conventional oral examination (COE); the examination was then repeated using Microlux/DL device and toluidine blue. Biopsy of suspicious lesions was performed. Also clinicians opinions regarding the two tools were obtained. Results: The sensitivity and, specificity and positive predictive value (PVP) of Microlux/DL for visualization of suspicious premalignant lesions considering COE as a gold standard (i.e screening device) were 94.3%, 99.6% and 96.2% respectively, while they were 100%, 32.4% and 17.9% when considering biopsy as a gold standard. Moreover, Microlux/DL enhanced detection of the lesion and uncovered new lesions compared to COE, whereas it did not alter the provisional clinical diagnosis, or alter the biopsy site. On the other hand, adding toluidine blue dye did not improve the effectiveness of the Microlux/DL system. Conclusions: The Microlux/DL seems to be a promising adjunctive screening device.