Analytical Sciences
Online ISSN : 1348-2246
Print ISSN : 0910-6340
ISSN-L : 0910-6340
Volume 36 , Issue 10
Showing 1-24 articles out of 24 articles from the selected issue
Highlights
Rapid Communications
  • Yuta MIKI, Hiroya MURAKAMI, Keisuke IIDA, Tomonari UMEMURA, Yukihiro E ...
    Type: Rapid Communications
    2020 Volume 36 Issue 10 Pages 1153-1155
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: September 18, 2020
    JOURNALS FREE ACCESS
    Supplementary material

    The handling of a particulate sorbent for solid-phase extraction is often troublesome because it causes static clinging and scattering. To overcome this problem, a production method for a simple molding-type solid-phase extraction medium (M-SPEM) was developed in this study by using commercially available adhesives. The content of a particulate sorbent can increase to as much as 85 wt% in the M-SPEM. Because of the high content, the proposed M-SPEMs have a higher specific surface area than previous monolithic media.

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Original Papers
  • Wenjie YU, Hengye LI, Lin ZHANG, Jing LIU, Fenying KONG, Wei WANG
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1157-1163
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: April 10, 2020
    JOURNALS FREE ACCESS
    Supplementary material

    In this study, efforts were made to prepare a porous aromatic framework (PAF) with build-in magnetic nanoparticles (Fe3O4-PAF) for use as an efficient adsorbent for the removal of organic pollutants from water. The Fe3O4-PAF showed good handleability and could be recovered easily by magnetic separation. As a proof of concept, the adsorption properties of Fe3O4-PAF were investigated to remove 2,4-dichlorophenol (2,4-DCP) and bisphenol A (BPA) from water. The Fe3O4-PAF showed a fast adsorption rate, high adsorption efficiency and high adsorption capacities. It adsorbed 2,4-DCP (0.1 mmol L−1) and BPA (0.1 mmol L−1) with pseudo-second-order rate constant (k2) of 2.1 and 3.54 g mg−1 min−1, respectively. According to the Langmuir isotherm model, the maximum adsorption capacities of 2,4-DCP and BPA onto Fe3O4-PAF were calculated to be 234.74 and 233.65 mg g−1, respectively. The Fe3O4-PAF also featured good tolerance to harsh conditions, facilitating its application in a real water environment. It could be regenerated easily and reused multiple times without obvious loss of efficiency. In summary, this study provides a general and effective way to improve the handleability of PAFs and expands the practical application of PAF-based materials.

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  • Yuqi ZHAO, Ruxin LIU, Xiaoqian CUI, Qingjie FU, Miao YU, Qiang FEI, Gu ...
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1165-1169
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: April 24, 2020
    JOURNALS FREE ACCESS
    Supplementary material

    Based on the anti-aggregation mechanism of citrate stabilized gold nanoparticle (AuNPs), a new specific and sensitive colorimetric sensor for thiocyanate (SCN) was developed. In this scheme, the AuNPs were aggregated in the presence of the aggregating agent 2-aminopyridine (2-AP) due to electrostatic attraction. The solution color changed from red to blue. When SCN was present, SCN formed a sulfur–gold bond with the AuNPs to protect the AuNPs from aggregation. Thiocyanate can be detected by the color change of the solution from blue to red. The results showed that the absorbance ratio A675/A520 was linear with the concentration of SCN in the range of 0.4 – 1.2 μmol L−1 by UV-Vis spectroscopy. The limit of detection (LOD) of this assay was 0.37 μmol L−1. The system also had excellent selectivity and anti-interference ability. In addition, this method was successfully used for the detection of SCN in actual water samples and achieved good results.

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  • Jie REN, Lan ZHANG, Lingling ZHAO, Xuemiao WANG, Wu YANG
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1171-1176
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 01, 2020
    JOURNALS FREE ACCESS

    Water-soluble carbon spheres (CS) were prepared by a facile one-step hydrothermal synthetic method using glucose as a carbon source and sodium hydroxide as additives. The morphology and the chemical structure were characterized by transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). In addition, the ultraviolet-visible (UV-vis) absorption spectrum and the fluorescence spectrum of the prepared CS were also investigated. The emission spectrum of the obtained CS depends on the excitation wavelength, which is similar to that of most carbon quantum dots. The fluorescence of the CS is quenched in the presence of Cr3+, Fe3+ and Hg2+. Based on this feature, the selective and sensitive detections of Cr3+, Fe3+ and Hg2+ were performed, and the detection limits were 6.72, 7.26, and 9.51 μM, respectively.

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  • Morihide HIGO, Masaru MITSUSHIO, Toshifumi YOSHIDOME, Sadafumi NAKATAK ...
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1177-1184
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 01, 2020
    JOURNALS FREE ACCESS

    Gold oxides (0.1 – 2.0 nm thick) prepared from gold films by an oxygen-dc glow discharge using a gold discharge ring for 0.17 – 30 min at room temperature were characterized by X-ray photoelectron spectroscopy. The oxide thickness increased with increasing discharge time in contrast to the use of an aluminum ring, and thicker oxide films were obtained. The O 1s spectra show four components: I, II, III, and IV. Components I, II, and IV appear during the early formation periods (≤0.5 min). Components I and II are stable and assigned to hydroxyl groups on the surfaces. Component IV changes into component III (gold oxide) after longer discharge times (≥1 min). The gold oxides (2.0 nm thick) decompose after 15 d at room temperature and decompose immediately at temperatures exceeding 117°C. They also decompose under ultraviolet light irradiation (254, 302, and 365 nm) and decompose more rapidly in water vapor at the shorter wavelengths. The thicker nature of the gold oxides is advantageous for their preservation, and they were preserved in their oxidized state for 196 d in anhydrous dodecane in a dark atmosphere.

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  • Hiroya MURAKAMI, Takuya SUGIYAMA, Yuta MIKI, Tomonari UMEMURA, Yukihir ...
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1185-1190
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: October 01, 2020
    JOURNALS FREE ACCESS

    Hydrophilic interaction chromatography (HILIC) has attractive attention for the separation of water-soluble compounds via HPLC. There are, however, few studies on the pretreatment of the HILIC-type solid-phase extraction (SPE) due to the difficulty of obtaining the HILIC-type sorbent. Therefore, the development of HILIC-type sorbents for SPE is essential. In this study, four different hydrophilic copolymers, namely diallylamine–maleic acid copolymer (DAM), diallylamine–acrylamide copolymer (DAA), allylamine–maleic acid copolymer (MAM), and partly methylcarbonylated allylamine acetate copolymer (MAC), were immobilized on glycidyl methacrylate (GMA)-base resin, and their adsorptive properties were evaluated. The results of the physical and adsorptive properties indicated that a balance between the water content of the water-enriched layer on sorbent and the amount of hydrophilic copolymer immobilized on the GMA-base resin was vital for the adsorption in HILIC-type sorbent for SPE.

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  • Qichen ZHANG, Jia YOU, Wenli ZHU, Zhigang WU, Jingyuan XIONG
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1191-1196
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 08, 2020
    JOURNALS FREE ACCESS

    A urinary organic acids profile can be utilized as an effective screening tool for analyzing abnormality of nutrient metabolism. By using these metabolic markers in conjunction with one another, it helps in understanding how individual nutrient metabolism is executed and to determine where there may be imbalances in the metabolic cycle. In this study, we developed a rapid quantification method of 20 urinary organic acids by HPLC-mass spectrometry. A pre-analytical process of organic acid extraction from a urine sample is crucial in this methodology. The process was accomplished by liquid–liquid extraction followed by strong anion exchange. Compared with previous methods, this method greatly reduces the analysis time and allows for the simultaneous quantification of 20 organic acids within 10 min for the first time. This methodology enabled us to analyze urine samples collected from 34 Chinese children. The abnormalities of some urinary organic acids were found in this group, which revealed evidence of functional inadequacy of specific nutrients. The preliminary data in this study confirmed the suitability of the method for rapid and accurate quantification of the target organic acids in urine samples.

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  • Hisashi HAYASHI, Mao TAKAISHI
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1197-1202
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 08, 2020
    JOURNALS FREE ACCESS

    Mn Kβ spectra of Mn, MnO, MnSO4·H2O, KMnO4, 0.50 M MnSO4 aqueous solution, and the precipitation bands of Mn-Fe-based Prussian blue analogs formed in 2.4 wt.% agarose gel (“Gel”) were measured using a laboratory-use X-ray setup with ∼2.6 eV instrumental resolution, which comprises a cylindrically bent Si (400) crystal monochromator and a spherically bent Ge (440) crystal analyzer. The oxidation-state dependent shift of the Mn Kβ1,3 peak (∼1 eV) was clearly observed for Mn, MnO, and KMnO4, confirming that the employed setup can acquire the key features of Mn Kβ spectra. The Mn Kβ spectra of MnSO4·H2O, the 0.50 M solution, and Gel exhibited small but distinguishable differences, whereas the spectra acquired at two positions in Gel were almost the same. These results suggest that highly resolved Mn Kβ spectra can be helpful for assessing ligand coordination around Mn atoms in gels and solutions.

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  • Wei ZENG, Dongyan HUANG, Gangbing ZHU, Baohe LV, Yinhui YI
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1203-1209
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 15, 2020
    JOURNALS FREE ACCESS
    Supplementary material

    In this work, by functionalizing MoS2 quantum dot with 3-aminobenzeneboronic acid, a novel multifunctional quantum dot (denoted as B-MoS2 QD) was obtained and used successfully for a fluorescence nanoprobe for detecting o-dihydroxybenzene (o-DHB). Transmission electron microscopy, fluorescence spectrum, UV-vis spectrum and fluorescence lifetime were used to investigate the prepared nanoprobe. The results show that the B-MoS2 QD nanoprobe can exhibit strong fluorescence and excellent light fastness owing to the coupled effect from the MoS2 QDs and boronic acid; interestingly, the vicinal diols structure from its surface can bridge covalently with o-DHB, resulting in the fluorescence quenching of B-MoS2 QDs and selective recognition toward o-DHB. With the increasing of o-DHB concentration, the nanoprobe fluorescence would gradually decrease. By measuring the fluorescence intensity of B-MoS2 QDs, a wide linear range from 0.1 to 200.0 μM with a low detection limit of 0.025 μM was obtained for o-DHB analysis; meanwhile, this fluorescence nanoprobe possesses excellent selectivity for the selective detection of o-DHB from its analogues.

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  • Toshinori MORISAKU, Miki SUNADA, Atsushi MIYAZAKI, Takaya SAKAI, Keiko ...
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1211-1215
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 15, 2020
    JOURNALS FREE ACCESS

    We developed an instrument that allows us to measure dynamic light scattering from soft materials on solid substrates by avoiding strong background due to the reflection light from substrates. In the instrument, samples on substrates are illuminated by evanescent-light field and the resultant scattered light from the samples is collected with a dark-field optical configuration by employing a high numerical aperture microscope objective. We applied the instrument to measure the dynamic properties of supported lipid bilayers (SLBs), which have been widely utilized in industries as functional materials such as biosensors. From the time course of the scattered light from the SLBs, the power spectrum with the broad peak ranging from 10 to 20 kHz is observed. The use of the microscope objectives enables us to apply the instrument to future light scattering imaging for dynamic properties of soft materials supported on various substrates by combining with conventional microscope systems.

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  • Hamideh TAFAZOLI, Mohadeseh SAFAEI, M. Reza SHISHEHBORE
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1217-1222
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 15, 2020
    JOURNALS FREE ACCESS

    This study describes a kinetic spectrophotometric method for accurate, sensitive and rapid determination of cisplatin in biofluids. The developed method is based on the inhibitory effect of cisplatin on the oxidization of Janus Green by bromate in acidic media. The change in absorbance as the criteria of the oxidation reaction was followed spectrophotometrically. To obtain the highest rate of sensitivity, efficient reaction parameters were optimized. Under optimum experimental conditions, a calibration graph was obtained linearly over the range 10.0 – 5750.0 μg L−1 and the limit of detection (3sb/m) was 4.2 μg L−1 of cisplatin. The interfering effect of diverse species was investigated. The developed method was used for the quantification of cisplatin in bio fluids of patients treated with cisplatin, spiked bio fluids and pharmaceutical samples and yielded satisfactory results.

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  • Ahmed KHAN, Muhammad ASGHAR, Mohammed YAQOOB
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1223-1230
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 22, 2020
    JOURNALS FREE ACCESS

    A novel method for the analysis of nalbuphine hydrochloride (NAL) is reported based on its enhancement effect on a diperiodatoargentate(III)-rhodamine-B (Ag(III) complex-Rh-B) chemiluminescence (CL) system in an aqueous sulfuric acid medium using flow-injection analysis (FIA). The optimal conditions of the CL reaction were: sulfuric acid, 10−2 M; Ag(III) complex, 2.0 × 10−4 M; Rh-B, 2.0 × 10−5 M; Brij-35, 0.01%; sample loop volume, 300 μL; and flow rate, 3.0 mL/min/stream. The limit of detection (LOD) and limit of quantification (LOQ) were 0.001 and 0.003 mg/L (S/N = 3 and 10); linear calibration range, 5 × 10−3 – 5.0 mg/L (R2 = 0.9999) and injection throughput, 150/h. The relative standard deviation (RSD) was from 0.8 – 3.2% over the range studied. The suggested technique was applied for the determination of NAL in pharmaceutical injections, compared with a reported spectrophotometric method, and obtained results were found to be satisfactory. Based on spectrophotometric studies, the most probable mechanism of the CL reaction has been briefly described and drawn schematically.

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  • Akira TSUJITA, Asami NAGASAKA, Hidehiko OKAZAKI, Shin OGAWA, Akinaga G ...
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1231-1236
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 29, 2020
    JOURNALS FREE ACCESS
    Supplementary material

    Here, we present a quantitative method for H2 detection by gas chromatography–selected ion monitoring–mass spectrometry (GC-SIM-MS) using a single quadrupole instrument. Additionally, the developed method was applied to the detection of H2 in human blood by GC-SIM-MS analysis using the existing 22Ne in air as an internal standard (IS). H2 was analyzed by GC-SIM-MS using a single quadrupole instrument with double TC-Molsieve 5A capillary columns for the separation of permanent gases. The detections of H2 (analyte) and 22Ne (IS) were performed at m/z 2 and 22, respectively, by GC-SIM-MS. The analyte and IS were separated using He as the carrier gas. The ratio of the peak area of H2 to 22Ne was employed to obtain a calibration curve for H2 determination in the gas phase. The proposed GC-SIM-MS method exhibited high sensitivity in terms of the limits of detection (LOD) (1.7 ppm) and quantitation (LOQ) (5.8 ppm) for H2 analysis. The developed quantitative assay of H2 in the headspace of blood samples achieved high repeatability with a relative standard deviation (RSD) of 1.4 – 4.7%. We successfully detected and quantified H2 in the headspaces of vacuum blood-collection tubes containing whole blood from 11 deceased individuals with several causes of death by employing the developed GC-SIM-MS method. The quantitative value of H2 ranged from 5 to 905 ppm. The proposed GC-SIM-MS method was applicable to the quantitative assay of H2 in biological samples without tedious pretreatment requirements.

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  • Yangyang WANG, Bo PAN, Mingjun ZHANG, Xinpeng DU, Weihong WU, Li FU, Q ...
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1237-1241
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 29, 2020
    JOURNALS FREE ACCESS

    The rapid identification of plant variety is valuable in both academic studies and crop production. However, rapid and accurate identification has been difficult because many varieties have very similar morphological characteristics and are susceptible to the effects of the growing environment. In this work, we established an electrochemical method for recording the electro-active profile of compounds in plant tissue. Because the chemical composition of different varieties is largely controlled by their genes, rather than a growing environment, this method has considerable potential for variety identification. Three varieties of Pueraria with sixteen locations were collected for confirming the feasibility of the proposed methodology. Principal component analysis and peak ratio analysis have been used for grouping the sample data. The results indicate the electrochemical profiles of three varieties can be distinguished using their voltammetric data.

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  • Masashi MIURA, Mamiko NOGAMI, Miho SAKAI, Miwa SATO, Takeshi YATSUSHIR ...
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1243-1249
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 29, 2020
    JOURNALS FREE ACCESS
    Supplementary material

    For improving quality control in the fermented tea production process and advancing the corresponding food labeling with function claims, a rapid and robust hesperidin analysis method using LC-MS/MS with the sample dilution approach was developed by following internationally accepted criteria of the Association of Official Analytical Chemists (AOAC). The linear correlation coefficient (r2) of the regression line was 0.9997 in the concentration range of 0.025 – 2.5 mg/L. The matrix effect evaluated using regression line slope values was negligible. The recovery rate of 100.7% indicated improved trueness. The performance of the newly developed method in determining the hesperidin content of fermented tea samples did not significantly vary from that of a well-established, conventional method. The HorRat values of intra- and inter-laboratory reproducibility studies were both within the acceptable range, indicating sufficient accuracy of the newly developed method according to the AOAC criteria.

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  • Ryoko TOMITA, Tadashi HAYAMA, Nao NISHIJO, Toshihiro FUJIOKA
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1251-1254
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 29, 2020
    JOURNALS FREE ACCESS

    A liquid chromatographic (LC) method with fluorous derivatization for the determination of cyanide in human plasma is described. In this method, the cyanide was transformed to a fluorous and fluorogenic compound by derivatizing with 2,3-naphthalenedialdehyde and perfluoroalkylamine reagent under mild reaction conditions (a reaction time of 5 min at room temperature). The obtained derivative was successfully retained on the perfluoroalkyl-modified LC column with the use of a high concentration of organic solvent in the mobile phase, whereas non-fluorous derivative was hardly retained, followed by fluorometric detection at excitation and emission wavelengths of 420 and 490 nm, respectively. Under the optimized conditions, the limit of detection and the limit of quantification for cyanide in a 5-μL injection volume were 1.3 μg/L (S/N = 3) and 4.4 μg/L (S/N = 10), respectively. The recovery from spiked human plasma was achieved in the range of 54 – 90% within a relative standard deviation of 3.5%. The feasibility of this method was further evaluated by applying it to the analysis of human plasma samples.

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  • Vadivel ARUNACHALAM, Cristabel M FERNANDES, Diksha C SALGAONKAR
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1255-1260
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 29, 2020
    JOURNALS FREE ACCESS
    Supplementary material

    The current study describes novel and quick methods for the quantification of K+ and Na+ in banana leaves using Horiba Laqua twin ion meters. Foliar K+ and Na+ content measured by ion meter significantly correlated with standard test values by coefficients of 0.83 and 0.46, respectively. About 48 absorbance values associated with potassium concentrations at wave numbers (1581 to 1583 and 3194 to 3410 cm−1) and 15 sodium associated wave numbers (3773 to 3996 cm−1) predicted potassium and sodium content with regression coefficients of 0.999 and 0.588, respectively. K+ and Na+ cations of fresh leaves in seven banana varieties were quantified using ion meters and new information of differences in the foliar potassium and sodium contents was found between banana varieties within the AAB group. The Rasbali (Silk subgroup) variety possessed greater potassium (5413 mg/L) and sodium (188 mg/L) ions than Amti (Mysore subgroup).

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  • Wilasinee SRIPROM, Aree CHOODUM, Chanadda PHAWACHALOTORN, Worawit WONG ...
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1261-1267
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: May 29, 2020
    JOURNALS FREE ACCESS

    A tetramethylammonium hydroxide (TMAH)-doped starch film was developed for trinitrotoluene (TNT) detection. A purple Janowsky anion was obtained from the reaction of TNT with released TMAH. When the film was used in conjunction with digital image colorimetry (DIC), rapid quantitative analysis of TNT was achieved. The Red-Green-Blue (RGB) intensities analyzed from digital photographs of the purple product were used to establish calibration curves for TNT. A wide linear range (2.5 to 50 mgL−1) with good linearity (R2 > 0.99) was achieved for the quantification of TNT. Good precision (1.73 to 3.74%RSD) was obtained for inter-day tests (n = 5). The films were applied to test four post-blast soil samples and two positive results were observed. The concentrations quantified by DIC were in good agreement with spectrophotometry. The film was able to be stored in a freezer for 3 months with <4.3% change in performance.

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  • Juneha BAK, Yoshiyuki MIYAZAKI, Hayato NAKANO, Toshiro MATSUI
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1269-1274
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: June 19, 2020
    JOURNALS FREE ACCESS

    Sulfated saccharides exhibit diverse physiological activities, but a lack of any convenient assay hinders their evaluation. Herein, an assay for the analysis of sulfated saccharides is described using 1H nuclear magnetic resonance (NMR) spectroscopy by employing ligands that can form ionic complexes with the sulfate groups. Based on the change in the chemical shift (Δδ) of the ligands by sulfated mono- to tetrasaccharide, imidazole was found to be a good ligand, showing the maximum Δδ; neutral saccharides do not show any change in the δ value. A marked and constant downfield δ value observed was changed dramatically at a molar ratio of >1:1 (imidazole:sulfated saccharides), allowing a sulfate content estimation based on the concentration of imidazole at the Δδ inflection point. By the proposed ligand-aided 1H NMR assay, the sulfate content of natural sulfated polysaccharide, fucoidan, was non-destructively estimated to be 2.1 mmol/g-fucoidan.

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  • Dang Huy HIEP, Yuta TANAKA, Hiroki MATSUBARA, Shoji ISHIZAKA
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1275-1278
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: June 19, 2020
    JOURNALS FREE ACCESS
    Supplementary material

    This paper describes a novel method for fabricating paper-based microfluidic devices using a laser beam scanning technique. Cellulose chromatography papers were treated with octadecyltrichlorosilane (OTS) to make them entirely hydrophobic. A photoacid generator (CPI-410S) was soaked into the paper, and irradiated with a 405-nm laser beam to induce acid generating reactions. Since the silyl ether bond between cellulose and OTS was cleaved by the hydrolysis reaction, the photo-irradiated area changed to hydrophilic. By scanning the laser beam using a Galvo mirror system, arbitrary shaped hydrophilic patterns were successfully created on the paper in 50 μm resolution. To the best of our knowledge, this is the first report on the fabrication of hydrophilic channels on the OTS-treated paper using photo-induced acid generation processes coupled with the laser beam scanning technique. Quantification of nitrite was demonstrated with the paper device made by this method.

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  • Haitao FENG, Akihiro KISHIMURA, Takeshi MORI, Yoshiki KATAYAMA
    Type: Original Papers
    2020 Volume 36 Issue 10 Pages 1279-1283
    Published: October 10, 2020
    Released: October 10, 2020
    [Advance publication] Released: July 03, 2020
    JOURNALS FREE ACCESS

    In the early stage of tumor development, tumor-associated macrophages (TAM) works to suppress tumor growth by secreting soluble factors including nitric oxide (NO). L-Arginine (Arg) is a substrate of nitric oxide synthase (NOS) expressed in TAM. Here we examined whether NO produced from Arg by macrophages works to enhance the effect of the anti-cancer drug, doxorubicin (Dox) by using a co-culture system of cancer cells with macrophages. By employing colorimetric analyses methods (Griess Reagent and Cell Counting kit-8), we found that NO produced from Arg by co-cultured macrophages could enhance the cytotoxic effect of Dox to cancer cells. Moreover, we found that augmentation is affected by the order of the addition of Arg and Dox. A prior addition of Arg to Dox and simultaneous addition showed the same enhancement effect, but a prior addition of Dox to Arg abolished the augmentation. This suggests that the co-administration of Arg with Dox would be an effective treatment to improve chemo-therapies.

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