• Title/Summary/Keyword: fluorescein

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Study of Equilibrium, Kinetic and Thermodynamic Parameters about Fluorescein Dye Adsorbed onto Activated Carbon (활성탄을 이용한 플루오레세인 염료 흡착에 대한 평형, 동력학 및 열역학 파라미터의 연구)

  • Lee, Jong-Jib;Um, Myeong Heon
    • Applied Chemistry for Engineering
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    • v.23 no.5
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    • pp.450-455
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    • 2012
  • The paper includes the utlization of an activated carbon as a potential adsorbent to remove a hazardous fluorescein dye from an aqueous solution. Batch adsorption experiments were carried out for the removal of fluorescein dyes using a granular activated carbon as an adsorbent. The effects of various parameters such as pH, amount of adsorbent, contact time, initial concentration and temperature of the adsoprtion system were investigated. The experimental results revealed that activated carbon exhibit high efficiencies to remove fluorescein dyes from the aqueous solution. The equilibrium process can be well described by Freundlich isotherm in the temperature range from 298 K to 318 K. From adsorption kinetic experiments, the adsorption process followed a pseudo second order kinetic model, and the adsorption rate constant ($k_2$) decreased with increasing the initial concentration of fluorescein. The free energy of adsorption ${\Delta}G^0$), enthalpy ${\Delta}H^0$), and entropy (${\Delta}S^0$) change were calculated to predict the nature adsorption. The estimated values for ${\Delta}G^0$ were -17.11~-20.50 kJ/mol over an activated carbon at 250 mg/L, indicated toward a spontaneous process. The positve value for ${\Delta}H^0$, 33.2 kJ/mol, indicates that the adsorption of fluorescein dyes on an activated carbon is an endothermic process.

Diagnosis of Early Dental Caries with Dye-Enhancing Quantitative Light-Induced Fluorescence (QLF) (정량 광유도 형광법(QLF)과 광활성제를 이용한 초기 치아우식증의 진단)

  • Kim, Mihee;Lee, Sangho;Lee, Nanyoung
    • Journal of the korean academy of Pediatric Dentistry
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    • v.42 no.3
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    • pp.218-225
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    • 2015
  • This study used sodium fluorescein to improve imaging diagnostic ability by increasing the fluorescence difference between sound enamel and caries lesions. It also made it easier to discriminate between stain and caries lesions using quantitative light-induced fluorescence (QLF). Half of the specimen surface was covered with nail varnish as a control. Specimens were divided randomly in six decalcification groups and decalcified for different lengths of time. Then, ${\Delta}F$ was measured using QLF-D. After applying 0.075% sodium fluorescein, we measured ${\Delta}F$ again and compared it with the initial value. After cutting the central portion of the specimen, we measured the lesion depth using scanning electron microscopy. The lesion surfaces observed with QLF were darker than normal enamel, whereas they were lighter than normal enamel after applying fluorescein. Longer decalcification time was associated with greater fluorescent dye penetration. The ${\Delta}F$ measured after applying fluorescein was higher than the initial value (p < 0.05). Due to QLF measurement using fluorescein being more sensitive for diagnosing early decalcification, this approach will enable early diagnosis of dental caries before the cavity formation stage, allowing the treatment of early caries lesions. With QLF and sodium fluorescein, we can easily discriminate between stain and caries lesions.

Langmuir Aggregation of Fluorescein Isothiocyanate (FITC) on Cetyl Trimethylammonium Bromide (CTAB) and Application to Determination of Anionic Detergent in Sewage

  • Gao, Hong-Wen;Zhou, De-Yan
    • Bulletin of the Korean Chemical Society
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    • v.23 no.1
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    • pp.29-34
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    • 2002
  • The microphase adsorption - spectral correction (MPASC) technique was described and applied to study the interaction of fluorescein isothiocyanate (FITC) with cetyl trimethylammonium bromide (CTAB). The synergism mechanism of micelle was analyzed and discussed. The aggregation of FITC on CTAB obeys the Langmuir monolayer adsorption. Results showed that the monomer and micellar aggregate is $FITC-CTAB_3$ and $(FITC-CTAB_3)_{29}$, respectively at pH 9.62. The adsorption constant of the CTAB-FITC aggregate was determined to be $2.10{\times}10^5$. Interestingly, it was observed for the addition of an anionic surfactant to desorb FITC from its CTAB aggregate and this has been applied to the quantitative determination of trace amounts of anionic detergent (AD) in sewage.

Local Feature Detection on the Ocular Fundus Fluorescein angiogram Using Relaxation Process (이완법을 이용한 형광안저화상의 국소특징 검출)

  • 高昌林
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.5
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    • pp.856-862
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    • 1987
  • An local adaptive image segmentatin algorithm for local feature detection and effective clustering of unimodal histogram shape are proposed. Local adaptive difference image and its histogram are obtained from the input image. The parameters are derived from the histogram and used for the segmentation based on relaxatin process. The results showed effective region segmentation and good noise cleaning for the ocular fundus fluorescein angiogram which has low contrast and unimodal histogram.

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Assessment of Mycobacterial Viability by Fluorospectrophotometry (형광분광측정법에 의한 항산균의 생명력 평가)

  • 이영남
    • Korean Journal of Microbiology
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    • v.24 no.2
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    • pp.147-153
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    • 1986
  • Viable potential of Mycobacterium smegmatis, a slow grower in vitro cultivation and of M. leprae, an obligate intracellular parasitic bacterium, which can not be cultured yet in vitro was assessed by fluorospectrophotometry. Bacterial cells in different numbers and under various physiological status were incubater with fluorescein diacetate(FDA). After an incubation of the bacterial preparations with FDA at specified conditions, amount of fluorescein inside bacteria was measured by a fluorospectrophotometer at 470nm and 510nm of excitation and emission wavelengths, respectively. Fluorounit given by such bacteria showed a correlation with assessment of viability of the same preparations made by other methods, such as optical density and colony forming units of M. smegmatis and intracellular ATP content of M. leprae. The possible use of fluorospectrophotometry in assessing viability or physiological potential of bacteria, particularly intracellular parasites and fastidious organisms to culture in vitro is discussed in relation to other methods.

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Geometric distortion correction of fluorescein ocular fundus photographs (형광 안저 사진의 기하 왜곡 교정)

  • 권갑현;하영호;김수중
    • Progress in Medical Physics
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    • v.2 no.2
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    • pp.183-192
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    • 1991
  • Ophthalmoscopy following the intravenous injection of fluorescein has gained great diagnostic importance in ophthalmology. This technique provides sequential evaluation of the anatomic and physiologic status of the choroidal and retinal vasculature. In order to detect the changes between fluorescein ocular fundus image frames, the direct subtraction of the two frames is inadequate because of geometric distortions and background gray level differences in two images. In this study, a scheme for the correction of the geometric distortions is proposed. Precise control point coordinate values for transformation functions are manually determined after the process including a series of blood vessel detection and thinning, and one frame is mapped to another, and then a geometric distortion corrected image is obtained. When the corrected image is used in interframe change detections, a sucessful result is ensured.

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Analysis for Concentration Range of Fluorescein Sodium (플루오레신나트륨의 농도 범위 분석)

  • Lee, Da-Ae;Kim, Yong-Jae;Yoon, Ki-Cheol;Kim, Kwang-Gi
    • Journal of Biomedical Engineering Research
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    • v.41 no.2
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    • pp.67-74
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    • 2020
  • Brain tumors or gliomas are fatal cancer species with high recurrence rates due to their strong invasiveness. Therefore, the goal of surgery is complete tumor resection. However, the surgery is difficult to distinguish the border because tumors and blood vessels have the same color tone and shape. The fluorescein sodium is used as a fluorescence contrast agent for boundary separation. When the external light source is irradiated, yellow fluorescence is expressed in the tumor, which helps distinguish between blood vessels and tumor boundaries. But, the fluorescence expression of fluorescence sodium depends on the concentration of fluorescein sodium and such analytical data is insufficient. The unclear fluorescence can obscure the boundaries between blood vessels and tumors. In addition, reduce the efficiency of fluorescence sodium use. This paper proposes a protocol of concentration range for fluorescence expression conditions. Fluorescent expression was observed using a near-infrared (NIR) color camera with corresponding dilution using normal saline in 1 ml microtube. The flunoresence emission density range is 1.00 mM to 0.15 mM. The fluorescence emission begin to 1.00 mM and the 0.15 mM discolor. The discolor is difficult to fluorescence emission condition obserbation. Thus, the maximum density range of the bright fluoresecein is 0.15 mM to 0.30 mM. When the concentration range of fluorescein sodium is analyzed based on the gradient of fluorescence expression and the power measurement, the brightest fluorescence is expected to facilitate the complete resection of the tumor. For the concentration range protocol, setting concentration ranges and analyzing fluorescence expression image according to saturation and brightness to find optimal fluorescence concentration are important. Concentration range protocols for fluorescence expression conditions can be used to find optimal concentrations of substances whose expression pattern varies with concentration ranges. This study is expected to be helpful in the boundary classification and resection of brain tumors and glioma.

Effects of Injectable Anesthetics on Fluorescein Retinal Angiographic Phases in Dogs

  • Jang, Jae-Young;Kim, Young-Sam;Kim, Won-Tae;Jung, Chang-Su;Kim, Hyun-Ah;Kim, Min-Su;Yi, Na-Young;Jeong, Man-Bok;Nam, Tchi-Chou;Seo, Kang-Moon
    • Journal of Veterinary Clinics
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    • v.25 no.6
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    • pp.488-493
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    • 2008
  • This study compared the effect of injectable combinations of anesthetics on each of the fluorescein angiographic phases in order to determine the most useful anesthetic combination for the procedure. Acepromazineketamine (AK), xylazine-ketamine (XK), diazepam-ketamine (DK) and zolazepam-tiletamine (ZT) group were administered randomly to 8 dogs with a two-week interval between different combination doses. The vital signs including the heart rate and arterial pressure were measured before anesthesia and every five minutes during anesthesia. Serial angiographic images were obtained after injecting a sodium fluorescein dye (25 mg/kg) and the onset time of arterial phase (AP), arteriovenous phase (AVP), early venous phase (EVP) and late venous phases (LVP) were recorded. The onset time of the AP, AVP and EVP were significantly slower in the AK and XK groups than in the DK and ZT groups. The total duration of the AP and AVP in the AK group was significantly longer than those in the ZT group. The heart rates were significantly higher in the DK and ZT groups. The arterial pressure was significantly higher in the AK and XK groups (p<0.05). There were significant differences in each angiographic onset time and duration depending on the changes in the heart rates and arterial pressure. The AK and XK groups showed a long angiographic duration allowing an accurate evaluation. Overall, it is believed that AK and XK are more useful for performing fluorescein retinal angiography than DK and ZT.

The Usefulness of Fluorescein Angiography and Alternative Tests for Assessment of Fundus Hemorrhage (안저 출혈 시 형광안저혈관조영술 및 대체 검사의 유용성)

  • Yeon, Je-Jin;Koo, Bon-Kyeong;Park, Sang-Ku
    • Korean Journal of Clinical Laboratory Science
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    • v.53 no.3
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    • pp.266-276
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    • 2021
  • Fundus hemorrhage refers to abnormalities in the retinal tissue and blood vessels. Therefore, when a hemorrhagic change in the fundus occurs, the ophthalmologist orders various ophthalmic tests to evaluate the degree of hemorrhage and determine the progress of the lesion before, during, and after treatment to accordingly establish a treatment plan. Currently, the most useful and universal fundus examination includes optical coherence tomography (OCT), fundus photography (FP), and fluorescein angiography (FAG). Existing fluorescein angiography test methods for establishing a treatment plan for severe fundus bleeding have limitations. The authors propose that peripheral pupil and the 5-quadrant method should be performed using ultra-wide-angle fluorescence fundus angiography (UWFFA). Using this method, it is possible to quickly determine the area to be described, avoid the radius of bleeding as much as possible, and provide the ophthalmologist with a range of damaged tissue and abnormal blood vessels. Nevertheless, there are cases in which ophthalmologists judge that fundus bleeding is so severe that ultra-wide-angle fluorescence fundus angiography is meaningless. In such cases, ophthalmic ultrasound and electroretinogram may be used in that order as alternative methods of examination. Therefore, some clinical situations require the use of ophthalmic ultrasound and electroretinogram and should be performed accurately.