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  1. Gill MR, Harun SN, Halder S, Boghozian RA, Ramadan K, Ahmad H, et al.
    Sci Rep, 2016 08 25;6:31973.
    PMID: 27558808 DOI: 10.1038/srep31973
    Ruthenium(II) polypyridyl complexes can intercalate DNA with high affinity and prevent cell proliferation; however, the direct impact of ruthenium-based intercalation on cellular DNA replication remains unknown. Here we show the multi-intercalator [Ru(dppz)2(PIP)](2+) (dppz = dipyridophenazine, PIP = 2-(phenyl)imidazo[4,5-f][1,10]phenanthroline) immediately stalls replication fork progression in HeLa human cervical cancer cells. In response to this replication blockade, the DNA damage response (DDR) cell signalling network is activated, with checkpoint kinase 1 (Chk1) activation indicating prolonged replication-associated DNA damage, and cell proliferation is inhibited by G1-S cell-cycle arrest. Co-incubation with a Chk1 inhibitor achieves synergistic apoptosis in cancer cells, with a significant increase in phospho(Ser139) histone H2AX (γ-H2AX) levels and foci indicating increased conversion of stalled replication forks to double-strand breaks (DSBs). Normal human epithelial cells remain unaffected by this concurrent treatment. Furthermore, pre-treatment of HeLa cells with [Ru(dppz)2(PIP)](2+) before external beam ionising radiation results in a supra-additive decrease in cell survival accompanied by increased γ-H2AX expression, indicating the compound functions as a radiosensitizer. Together, these results indicate ruthenium-based intercalation can block replication fork progression and demonstrate how these DNA-binding agents may be combined with DDR inhibitors or ionising radiation to achieve more efficient cancer cell killing.
    Matched MeSH terms: Quinolines/toxicity
  2. Goh BS, Ismail MI, Husain S
    J Laryngol Otol, 2014 Mar;128(3):242-8.
    PMID: 24618303 DOI: 10.1017/S002221511400036X
    This study investigated improvements in quality of life associated with eight weeks of montelukast and/or intranasal steroid treatment for moderate to severe allergic rhinitis.
    Matched MeSH terms: Quinolines/therapeutic use*
  3. Hui CK, Hui NK
    Gut Liver, 2018 May 15;12(3):288-296.
    PMID: 29212311 DOI: 10.5009/gnl17056
    Background/Aims: The epidemiology of eosinophilic gastroenteritis remains unclear. We aim to determine the prevalence of eosinophilic gastroenteritis in patients with lower abdominal symptoms.

    Methods: In a prospective study, colonoscopy was performed on 2,469 consecutive patients. Biopsies were taken from the terminal ileum and ascending, transverse, descending and sigmoid colon in all patients.

    Results: Sixty-four of the 2,469 patients (2.6%) had eosinophilic gastroenteritis. Only five of the 64 patients (7.8%) with eosinophilic gastroenteritis had endoscopic mucosal abnormalities during colonoscopy. Six of these 64 patients (9.4%) had severe disease at presentation, and seven of these 64 patients (10.9%) required systemic steroid treatment. An elevated absolute peripheral eosinophil count was independently associated with severe disease at presentation (4/6 [66.7%] vs 3/58 [5.2%], p=0.005; odds ratio [OR], 25.320; 95% confidence interval [CI], 2.628 to 243.910), and severe disease at the time of presentation was independently associated with the use of systemic steroid treatment (6/7 [85.7%] vs 0/57 [0%], p=0.008; OR, 18.021; 95% CI, 2.163 to 150.152).

    Conclusions: The prevalence of eosinophilic gastroenteritis is common, and patients usually present normal-appearing mucosa on colonoscopy. Those with severe disease at presentation usually have a raised absolute peripheral eosinophil count and should be commenced on systemic steroids as an initial therapy.

    Matched MeSH terms: Quinolines/administration & dosage
  4. Ahmad A, Waseem T, Butt NF, Randhawa FA, Malik U, Shakoori TA
    Trop Biomed, 2018 Dec 01;35(4):1115-1122.
    PMID: 33601858
    A significant percentage of dengue patients develop Dengue Shock Syndrome (DSS) which is characterized by increased vascular permeability, circulatory failure and often death. Montelukast, a cysteinyl leukotriene receptor antagonist regulates vascular permeability and we hypothesized that it may be effective in protecting against DSS. An open label, parallel, randomized controlled trial (RCT) was thus carried out at Mayo Hospital, Department of Medicine, Lahore. A total of 200 patients of dengue fever were recruited and randomized into two groups. The group A was treated with Montelukast 10 mg once daily for 5 days along with general supportive treatment. Group B received the standard supportive treatment and served as the control group. The frequency of DSS was compared in the two groups by Chi square test. A binary logistic regression analysis was conducted to assess the effects of montelukast treatment on onset of DSS after adjusting for gender, age, white cell count, platelet count, haematocrit, serum alanine transaminase (ALT) and aspartate transaminase (AST). Relative risk (RR), absolute risk reduction (ARR), relative risk reduction (RRR) and numbers needed to treat (NNT) were calculated. Significance level was set at p0.001, Odds ratio=5.01, 95% CI=2.17-11.60) even after adjusting for confounders. Montelukast reduced the absolute risk (ARR=22%) and the relative risk (RRR=71%) of DSS in dengue fever. Numbers needed to treat were 4.55. We thus conclude that treatment with oral montelukast may protect patients of dengue fever from DSS and greatly reduce mortality.
    Matched MeSH terms: Quinolines
  5. Norazah A, Lim VKE, Rohani MY, Kamel AGM
    Med J Malaysia, 2005 Oct;60(4):411-5.
    PMID: 16570701
    The in-vitro susceptibility of quinupristin/dalfopristin, levofloxacin and moxifloxacin against methicillin-resistant Staphylococcus aureus (MRSA) strains, which are also resistant to fusidic acid and rifampicin were carried out to determine whether these antibiotics can be used as an alternative treatment for multiply resistant MRSA strains. The minimum inhibitory concentrations (MIC) of these antibiotics were determined by E-test. Quinupristin/dalfopristin had good activity (MIC90 = 1 mg/L) against these strains while most of the strains showed intermediate resistance to moxifloxacin with MIC90 = 2 mg/L). However, more than 90% of these strains were resistant to levofloxacin with the MICs that ranged from 8 mg/L to 16 mg/L with the majority inhibited at 8 mg/L.
    Matched MeSH terms: Quinolines/pharmacology*
  6. Mungthin M, Watanatanasup E, Sitthichot N, Suwandittakul N, Khositnithikul R, Ward SA
    Am J Trop Med Hyg, 2017 03;96(3):624-629.
    PMID: 28044042 DOI: 10.4269/ajtmh.16-0668
    Piperaquine combined with dihydroartemisinin is one of the artemisinin derivative combination therapies, which can replace artesunate-mefloquine in treating uncomplicated falciparum malaria in Thailand. The aim of this study was to determine the in vitro sensitivity of Thai Plasmodium falciparum isolates against piperaquine and the influence of the pfmdr1 gene on in vitro response. One hundred and thirty-seven standard laboratory and adapted Thai isolates of P. falciparum were assessed for in vitro piperaquine sensitivity. Polymorphisms of the pfmdr1 gene were determined by polymerase chain reaction methods. The mean and standard deviation of the piperaquine IC50 in Thai isolates of P. falciparum were 16.7 ± 6.3 nM. The parasites exhibiting chloroquine IC50 of ≥ 100 nM were significantly less sensitive to piperaquine compared with the parasite with chloroquine IC50 of < 100 nM. No significant association between the pfmdr1 copy number and piperaquine IC50 values was found. In contrast, the parasites containing the pfmdr1 86Y allele exhibited significantly reduced piperaquine sensitivity. Before nationwide implementation of dihydroartemisinin-piperaquine as the first-line treatment in Thailand, in vitro and in vivo evaluations of this combination should be performed especially in areas where parasites containing the pfmdr1 86Y allele are predominant such as the Thai-Malaysian border.
    Matched MeSH terms: Quinolines/pharmacology*
  7. Jahurul MH, Jinap S, Ang SJ, Abdul-Hamid A, Hajeb P, Lioe HN, et al.
    PMID: 20589547 DOI: 10.1080/19440041003801190
    The intake of heterocyclic amines is influenced by the amount and type of meat and fish ingested, frequency of consumption, cooking methods, cooking temperature, and duration of cooking. In this study, the dietary intake of heterocyclic amines in Malaysia and their main sources were investigated. Forty-two samples of meat and fish were analysed by high-performance liquid chromatography with photodiode array detector to determine the concentration of the six predominant heterocyclic amines, namely: 2-amino-3-methylimidazo[4,5-f] quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f] quinoline(MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f] quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f] quinoxaline (4,8-DiMeIQx), 2-amino-3,7,8-trimethylimidazo[4,5-f] quinoxaline (7,8-DiMeIQx), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Dietary intake data were obtained using a food-frequency questionnaire when interviewing 600 Malaysian respondents. The level of total heterocyclic amines in food samples studies ranged from not detected to 38.7 ng g(-1). The average daily intake level of heterocyclic amine was 553.7 ng per capita day(-1). The intake of PhIP was the highest, followed by MeIQx and MeIQ. The results reveal that fried and grilled chicken were the major dietary source of heterocyclic amines in Malaysia. However, the heterocyclic amine intake by the Malaysian population was lower than those reported from other regions.
    Matched MeSH terms: Quinolines/administration & dosage; Quinolines/analysis
  8. Lee WT, Tan BK, Eng SA, Yuen GC, Chan KL, Sim YK, et al.
    Food Funct, 2019 Sep 01;10(9):5759-5767.
    PMID: 31453615 DOI: 10.1039/c9fo01357a
    A strategy to circumvent the problem of multidrug resistant pathogens is the discovery of anti-infectives targeting bacterial virulence or host immunity. Black sea cucumber (Holothuria atra) is a tropical sea cucumber species traditionally consumed as a remedy for many ailments. There is a paucity of knowledge on the anti-infective capacity of H. atra and the underlying mechanisms involved. The objective of this study is to utilize the Caenorhabditis elegans-P. aeruginosa infection model to elucidate the anti-infective properties of H. atra. A bioactive H. atra extract and subsequently its fraction were shown to have the capability of promoting the survival of C. elegans during a customarily lethal P. aeruginosa infection. The same entities also attenuate the production of elastase, protease, pyocyanin and biofilm in P. aeruginosa. The treatment of infected transgenic lys-7::GFP worms with this H. atra fraction restores the repressed expression of the defense enzyme lys-7, indicating an improved host immunity. QTOF-LCMS analysis revealed the presence of aspidospermatidine, an indole alkaloid, and inosine in this fraction. Collectively, our findings show that H. atra possesses anti-infective properties against P. aeruginosa infection, by inhibiting pathogen virulence and, eventually, reinstating host lys-7 expression.
    Matched MeSH terms: Quinolines/pharmacology; Quinolines/chemistry
  9. Smedley CJ, Stanley PA, Qazzaz ME, Prota AE, Olieric N, Collins H, et al.
    Sci Rep, 2018 Jul 13;8(1):10617.
    PMID: 30006510 DOI: 10.1038/s41598-018-28880-2
    The jerantinine family of Aspidosperma indole alkaloids from Tabernaemontana corymbosa are potent microtubule-targeting agents with broad spectrum anticancer activity. The natural supply of these precious metabolites has been significantly disrupted due to the inclusion of T. corymbosa on the endangered list of threatened species by the International Union for Conservation of Nature. This report describes the asymmetric syntheses of (-)-jerantinines A and E from sustainably sourced (-)-tabersonine, using a straight-forward and robust biomimetic approach. Biological investigations of synthetic (-)-jerantinine A, along with molecular modelling and X-ray crystallography studies of the tubulin-(-)-jerantinine B acetate complex, advocate an anticancer mode of action of the jerantinines operating via microtubule disruption resulting from binding at the colchicine site. This work lays the foundation for accessing useful quantities of enantiomerically pure jerantinine alkaloids for future development.
    Matched MeSH terms: Quinolines/isolation & purification; Quinolines/chemistry
  10. Moniruzzaman M, Rodríguez I, Ramil M, Cela R, Sulaiman SA, Gan SH
    Talanta, 2014 Nov;129:505-15.
    PMID: 25127626 DOI: 10.1016/j.talanta.2014.06.019
    The performance of gas chromatography (GC) combined with a hybrid quadrupole time-of-flight (QTOF) mass spectrometry (MS) system for the determination of volatile and semi-volatile compounds in honey samples is evaluated. After headspace (HS) solid-phase microextraction (SPME) of samples, the accurate mass capabilities of the above system were evaluated for compounds identification. Accurate scan electron impact (EI) MS spectra allowed discriminating compounds displaying the same nominal masses, but having different empirical formulae. Moreover, the use of a mass window with a width of 0.005 Da provided highly specific chromatograms for selected ions, avoiding the contribution of interferences to their peak areas. Additional information derived from positive chemical ionization (PCI) MS spectra and ion product scan MS/MS spectra permitted confirming the identity of novel compounds. The above possibilities are illustrated with examples of honey aroma compounds, belonging to different chemical classes and containing different elements in their molecules. Examples of compounds whose structures could not be described are also provided. Overall, 84 compounds, from a total of 89 species, could be identified in 19 honey samples from 3 different geographic areas in the world. The suitability of responses measured for selected ions, corresponding to above species, for authentication purposes is assessed through principal components analysis.
    Matched MeSH terms: Quinolines/chemistry
  11. Yew KL, Lee WC
    Med J Malaysia, 2012 Aug;67(4):420-1.
    PMID: 23082454 MyJurnal
    Matched MeSH terms: Quinolines/adverse effects*
  12. Chin WK, Lee SWH
    Int J Clin Pharm, 2018 Oct;40(5):963-976.
    PMID: 29777328 DOI: 10.1007/s11096-018-0655-3
    Background Atopic dermatitis (AD) is the most common form of eczema. As leukotriene mediators are involved in the inflammatory phase of atopic dermatitis, montelukast has been suggested as a possible therapy. Aim of the review To evaluate the safety and efficacy of montelukast off-label use for the treatment atopic dermatitis. Method A search was performed from database inception until March 2018 in six electronic databases for randomized-controlled-trials examining the use of montelukast for AD. Results Among 301 articles screened, 11 studies met the inclusion criteria and were included in the review. The study populations consist of paediatric and adult subjects with moderate-to-severe AD. Montelukast use was shown to improve symptoms such as pruritus in four studies. Another 2 studies reported that montelukast could improve symptoms similar to the standard regimen of topical steroid and oral antihistamine. However, five studies reported that montelukast had no effects in symptoms alleviation. The use of montelukast was associated with a similar safety profile to placebo and well-tolerated with minimal adverse effects. Conclusion There is limited evidence to suggest that the off-label use of montelukast is effective in treating moderate-to-severe AD. Further research with larger study populations employing standardized endpoint measuring instrument is warranted to further investigate the off-label use of montelukast in AD treatment. Until then, the use of conventional treatments including optimal daily skin hydration should remain the mainstay in the management of atopic dermatitis. In fact, for moderate-to-severe condition, steroid sparing immune-suppressants should still be used clinically until more effective and safer alternative is discovered.
    Matched MeSH terms: Quinolines/therapeutic use*
  13. Lai MY, Ooi CH, Lau YL
    Malar J, 2021 Mar 25;20(1):166.
    PMID: 33766038 DOI: 10.1186/s12936-021-03707-0
    BACKGROUND: As an alternative to PCR methods, LAMP is increasingly being used in the field of molecular diagnostics. Under isothermal conditions at 65 °C, the entire procedure takes approximately 30 min to complete. In this study, we establish a sensitive and visualized LAMP method in a closed-tube system for the detection of Plasmodium knowlesi.

    METHODS: A total of 71 malaria microscopy positive blood samples collected in blood spots were obtained from the Sarawak State Health Department. Using 18s rRNA as the target gene, nested PCR and SYBR green I LAMP assay were performed following the DNA extraction. The colour changes of LAMP end products were observed by naked eyes.

    RESULTS: LAMP assay demonstrated a detection limit of 10 copies/µL in comparison with 100 copies/µL nested PCR. Of 71 P. knowlesi blood samples collected, LAMP detected 69 microscopy-positive samples. LAMP exhibited higher sensitivity than nested PCR assay. The SYBR green I LAMP assay was 97.1% sensitive (95% CI 90.2-99.7%) and 100% specific (95% CI 83.2-100%). Without opening the cap, incorporation of SYBR green I into the inner cap of the tube enabled the direct visualization of results upon completion of amplification. The positives instantaneously turned green while the negatives remained orange.

    CONCLUSIONS: These results indicate that SYBR green I LAMP assay is a convenient diagnosis tool for the detection of P. knowlesi in remote settings.

    Matched MeSH terms: Quinolines/chemistry*
  14. Teng H, Chen Y, Lin X, Lv Q, Chai TT, Wong FC, et al.
    Food Chem Toxicol, 2019 Jul;129:138-143.
    PMID: 31034934 DOI: 10.1016/j.fct.2019.04.043
    The aim of this study was to assess the inhibitory effects of Sonchus olearleu extract on the generation of heterocyclic amines in roasted pork patties cooked by pan-frying. All samples were cooked for two different durations (45 min and 105 min) under 200 °C and 230 °C. 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-ami- no-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinox-aline (4,8-DiMeIQx), harman, and norharman were detected and quantified. In patties cooked at 230 °C for 105 min, S. olearleu extract (0.5%) significantly inhibited the formation of IQ, harman, and norharman by 39%, 67%, and 63%, respectively. In contrast to IQ, the levels of harman and norharman were significantly reduced by the extracts tested. However, no such effects were observed for MeIQx and 4, 8-DiMeIQx. Notably, the inhibitory effect on heterocyclic amines is significantly correlated with the antioxidant potential and total phenolic content of S. olearleu extract.
    Matched MeSH terms: Quinolines
  15. Khanam R, Hejazi II, Shahabuddin S, Bhat AR, Athar F
    J Pharm Anal, 2019 Apr;9(2):133-141.
    PMID: 31011470 DOI: 10.1016/j.jpha.2018.12.002
    1, 3, 4-Oxadiazole derivatives (4a-5f) were previously synthesized to investigate their anticancer properties. However, studies relating to their antioxidant potential and signal transducer and activator of transcription (STAT) inhibition have not been performed. We investigated previously synthesized 1, 3, 4-oxadiazole derivatives (4a-5f) for various radical scavenging properties using several in vitro antioxidant assays and also for direct inhibition of STAT3 through molecular docking. The data obtained from various antioxidant assays such as 2, 2,-diphenyl-1-picrylhydrazyl radical (DPPH), nitric oxide, hydrogen peroxide, and superoxide anion radical revealed that among all the derivatives, compound 5e displayed high antioxidant activities than the standard antioxidant L-ascorbic acid. Additionally, the total reduction assay and antioxidant capacity assay further confirmed the antioxidant potential of compound 5e. Furthermore, the molecular docking studies performed for all derivatives along with the standard inhibitor STX-0119 showed that binding energy released in direct binding with the SH2 domain of STAT3 was the highest for compound 5e (-9.91kcal/mol). Through virtual screening, compound 5e was found to exhibit optimum competency in inhibiting STAT3 activity. Compound 5e decreased the activation of STAT3 as observed with Western blot. In brief, compound 5e was identified as a potent antioxidant agent and STAT3 inhibitor and effective agent for cancer treatment.
    Matched MeSH terms: Quinolines
  16. Pan B, Pei FQ, Ruan CW, Lin RX, Cen YZ, Liu MR, et al.
    PMID: 30141606
    Objective: To diagnose and treat the first imported active case of Plasmodium knowlesi infection in China.

    Methods: The clinical information of the patient was collected. Microscopy of blood smear was conducted after Giemsa staining. Genomic DNA was extracted from blood, and PCR was conducted to amplify rDNA. The PCR products were sequenced and analyzed with BLAST

    Results: The patient returned from a one-week tour in a tropical rain forest in Malaysia. The first disease attack occurred in Guangzhou on Oct. 16, 2014, with fever, shivering and sweating. The patient was initially diagnosed as malaria and hospitalized on Oct. 26, 2014. Microscopic observation revealed typical forms of P. knowlesi in blood smear. The red blood cells became enlarged, with big trophozoites appearing as a ring with dual cores and dark brown malaria pigment. The trophozoites were slightly bigger and thicker than P. falciparum. The schizont had 6-8 merozoites, with obvious brown malaria pigment. PCR resulted in a specific band of 1 099 bp. BLAST analysis showed that the sequence of the PCR product was 99% homologous to P. knowlesi (acession No. AM910985.1, L07560.1 and AY580317.1). The patient was diagnosed as P. knowlesi infection, and was then given an 8-day treatment with chloroquine and primaquine, together with dihydroartemisinin piperaquine phosphate tablet. The patient was discharged after recovery on Oct. 28, 2014.

    Conclusion: According to the clinical symptoms, epidemiological history and laboratory test, the patient has been confirmed as P. knowlesi infection. It may also be the first active case of knowlesi malaria reported in China.

    Matched MeSH terms: Quinolines
  17. Iwata H, Masuda N, Kim SB, Inoue K, Rai Y, Fujita T, et al.
    Future Oncol, 2019 Jul;15(21):2489-2501.
    PMID: 31140297 DOI: 10.2217/fon-2019-0143
    Aim: To evaluate the efficacy and safety of neratinib as extended adjuvant therapy in patients from Asia based on exploratory analyses of the Phase III ExteNET trial. Patients & methods: A total of 2840 women with early stage HER2-positive breast cancer were randomly assigned to neratinib 240 mg/day or placebo for 1 year after trastuzumab-based adjuvant therapy. Results: A total of 341 patients were from Asia (neratinib, n = 165; placebo, n = 176). 2-year invasive disease-free survival rates were 92.8 and 90.8% with neratinib and placebo, respectively (HR: 0.70; 95% CI: 0.31-1.55), and 5-year rates were 91.9 and 87.2%, respectively (HR: 0.57; 95% CI: 0.27-1.13). Diarrhea was the most common adverse event with neratinib. Conclusion: Extended adjuvant therapy with neratinib reduces disease recurrences in Asian women with HER2-positive breast cancer. Trial registration: Clinicaltrials.gov NCT00878709.
    Matched MeSH terms: Quinolines/administration & dosage; Quinolines/adverse effects; Quinolines/therapeutic use*
  18. Siti Zulaikha Ghozali, Mohd Nazri Ismail, Nor Hazwani Ahmad
    MyJurnal
    The biosynthesis of nanoparticles has been proposed as a cost-effective and environmental friendly alternative to chemical and physical methods. The present study was aimed to characterise Catharanthus roseus (C. roseus)-silver nanoparticles (AgNPs) using a standardised C. roseus aqueous extract. Methods: The standardisation was performed by using Liquid Chromatography/Time-of-Flight ion trap Mass Spectrometry. An optimised C. roseus-AgNPs have been previously synthesised. Further characterisation of C. roseus-AgNPs was evaluated by zeta potential analysis and fourier transform infrared spectroscopy (FTIR). Results: The chromatography analysis has revealed presence of thirteen possible indole alkaloids in C. roseus extract which were lochrovicine, lochnerine, vinleurosine, vindolinine, tabersonine, catharanthine, serpentine, catharosine, vincristine, catharine, ajmalicine, vinleurosine, and vindolicine. Zeta potential analysis exhibited the value at -16.6 mV. FTIR spectrum of C. roseus aqueous extract showed the absorption band at 3210.83 cm-1 (C-H stretch), 2934.11 (C-H bond), 1578.15 (N=O stretch), 1388.76 and 1314.89 (N=O bend), 1119.29 (C-O bond) and 729.94 (C-Cl bond). In comparison, FTIR spectrum of C. roseus-AgNP s showed the absorption band at 2925.01 and 2924.97 (C-H bond), 1622.93 (C-C=C symmetric stretch), 1383.19 and 1384.13 (N-O bend), 1037.92/1038.76/1238.3/1117.2 (C-O bond), 3169.4 (O-H bond), 774.59 and 691.53 (C-Cl bond). Conclusion: The present findings have shown that the C. roseus aqueous extract contains alkaloids that may responsible as reducing and stabilising agents in the synthesis of AgNPs.
    Matched MeSH terms: Quinolines
  19. Zainul R, Abd Azis N, Md Isa I, Hashim N, Ahmad MS, Saidin MI, et al.
    Sensors (Basel), 2019 Feb 22;19(4).
    PMID: 30813385 DOI: 10.3390/s19040941
    This paper presents the application of zinc/aluminium-layered double hydroxide-quinclorac (Zn/Al-LDH-QC) as a modifier of multiwalled carbon nanotubes (MWCNT) paste electrode for the determination of bisphenol A (BPA). The Zn/Al-LDH-QC/MWCNT morphology was examined by a transmission electron microscope and a scanning electron microscope. Electrochemical impedance spectroscopy was utilized to investigate the electrode interfacial properties. The electrochemical responses of the modified electrode towards BPA were thoroughly evaluated by using square-wave voltammetry technique. The electrode demonstrated three linear plots of BPA concentrations from 3.0 × 10-8⁻7.0 × 10-7 M (R² = 0.9876), 1.0 × 10-6⁻1.0 × 10-5 M (R² = 0.9836) and 3.0 × 10-5⁻3.0 × 10-4 M (R² = 0.9827) with a limit of detection of 4.4 × 10-9 M. The electrode also demonstrated good reproducibility and stability up to one month. The presence of several metal ions and organic did not affect the electrochemical response of BPA. The electrode is also applicable for BPA determination in baby bottle and mineral water samples with a range of recovery between 98.22% and 101.02%.
    Matched MeSH terms: Quinolines
  20. Akanbi FS, Yusof NA, Abdullah J, Sulaiman Y, Hushiarian R
    Sensors (Basel), 2017 Jul 01;17(7).
    PMID: 28671561 DOI: 10.3390/s17071538
    Carbon nanotubes (CNTs) reinforced with gold nanoparticles (AuNPs) and chitosan nanoparticles (CTSNPs) were anchored on a screen-printed electrode to fabricate a multi-walled structure for the detection of quinoline. The surface morphology of the nanocomposites and the modified electrode was examined by an ultra-high resolution field emission scanning electron microscope (FESEM), and Fourier-transform infrared (FT-IR) spectroscopy was used to confirm the presence of specific functional groups on the multi-walled carbon nanotubes MWCNTs. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) were used to monitor the layer-by-layer assembly of ultra-thin films of nanocomposites on the surface of the electrode and other electrochemical characterizations. Under optimized conditions, the novel sensor displayed outstanding electrochemical reactivity towards the electro-oxidation of quinoline. The linear range was fixed between 0.0004 and 1.0 μM, with a limit of detection (LOD) of 3.75 nM. The fabricated electrode exhibited high stability with excellent sensitivity and selectivity, specifically attributable to the salient characteristics of AuNPs, CTSNPs, and MWCNTs and the synergistic inter-relationship between them. The newly developed electrode was tested in the field. The Ipa increased with an increase in the amount of quinoline solution added, and the peak potential deviated minimally, depicting the real capability of the newly fabricated electrode.
    Matched MeSH terms: Quinolines
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