scholarly journals Development of an LC-NMR System Using a Diode Array Detector and a Charged Aerosol Detector

2020 ◽  
Vol 69 (3) ◽  
pp. 151-155
Author(s):  
Yayoi KANBAYASHI ◽  
Yu TSUTSUMI ◽  
Toshimi MIZUKOSHI ◽  
Hideyuki YAMAGUCHI
Keyword(s):  
Array Detector ◽  
Diode Array ◽  
Diode Array Detector ◽  
Charged Aerosol ◽  
Charged Aerosol Detector

scholarly journals Determining High-Intensity Sweeteners in White Spirits Using an Ultrahigh Performance Liquid Chromatograph with a Photo-Diode Array Detector and Charged Aerosol Detector

Molecules ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 40 ◽  
Author(s):  
Kang Ma ◽  
Xiaojia Li ◽  
Yiwen Zhang ◽  
Fei Liu
Keyword(s):  
Correlation Coefficients ◽  
Array Detector ◽  
Diode Array ◽  
Diode Array Detector ◽  
Liquid Chromatograph ◽  
Limits Of Detection ◽  
Photo Diode ◽  
Charged Aerosol ◽  
Charged Aerosol Detector ◽  
Relative Standard

In China, white spirit is not only an alcoholic drink but also a cultural symbol. A novel and accurate method for simultaneously determining nine sweeteners (most authorized for use in China) in white spirits by ultrahigh performance liquid chromatography (UHPLC) with a photo-diode array detector (PDA) and charged aerosol detector (CAD) was developed. The sweeteners were acesulfame, alitame, aspartame, dulcin, neotame, neohesperidine dihydrochalcone, saccharin, sodium cyclamate, and sucralose. The sweeteners were separated within 16 min using a BEH C18 column and linear gradient-elution program. The optimized method allowed low concentrations (micrograms per gram) of sweeteners to be simultaneously detected. The CAD gave good linearities (correlation coefficients > 0.9936) for all analytes at concentrations of 0.5 to 50.0 μg/g. The limits of detection were 0.16 to 0.77 μg/g. Acesulfame, dulcin, neohesperidine dihydrochalcone, and saccharin were determined using the PDA detector, which gave correlation coefficients > 0.9994 and limits of detection of 0.16 to 0.22 μg/g. The recoveries were 95.1% to 104.9% and the relative standard deviations were 1.6% to 3.8%. The UHPLC-PDA-CAD method is more convenient and cheaper than LC-MS/MS methods. The method was successfully used in a major project called “Special Action against Counterfeit and Shoddy white spirits” and to monitor risks posed by white spirits in China.

DETERMINATION OF CHLORHEXIDINE DIGLUCONATE IN DISINFECTANTS

2018 ◽  
Vol 61 (8) ◽  
pp. 4
Author(s):  
Sergey V. Andreev ◽  
Evgeny S. Belyaev ◽  
Anna O. Ivanova ◽  
Elvina A. Novikova ◽  
Anatoly A. Ishchenko
Keyword(s):  
Bromophenol Blue ◽  
Array Detector ◽  
Diode Array ◽  
Blue Color ◽  
Chlorhexidine Digluconate ◽  
Diode Array Detector ◽  
Charged Aerosol ◽  
Charged Aerosol Detector ◽  
Wide Range

Chlorhexidine digluconate has been widely used in lenticular compositions, skin antiseptics and other ready-to-use disinfectants. This is due to its low toxicity, as well as a wide range of antimicrobial effects. A commonly used method for the analysis of commercially available chlorhexidine digluconate (usually available as a 20% aqueous solution) is high-performance liquid chromatography. In this article, the main methods of analysis used to determine chlorhexidine digluconate in disinfectants and skin antiseptics are considered. A new simple technique for the determination of chlorhexidine digluconate in technical products and disinfectants based on acid-base titration in alcohol-ketone is developed. It is shown that in this medium hydrochloric acid interacts with two nitrogen atoms of the chlorhexidine digluconate molecule. The end point of the titration is established by the transition of the blue color to green in the presence of bromophenol blue. The range of measured concentrations is from 0.1 to 2.0 mass%. The relative error of the method is 2.5% with the confidence probability P = 0.95. A comparison of the diode array detector and the charged aerosol detector for the determination of chlorhexidine digluconate has been performed. It is shown that a charged aerosol detector can be used to analyze chlorhexidine digluconate in cases where it is difficult to analyze with an ultraviolet or diode array detector. However, the sensitivity of the detector of charged aerosols is significantly lower than that of the diode matrix, and the linearity range is smaller. All methods were tested on model samples, as well as on samples of disinfectants, skin antiseptics, soaps and wipes with antibacterial effect.

scholarly journals Analysis of the Mycosporine-Like Amino Acid (MAA) Pattern of the Salt Marsh Red Alga Bostrychia scorpioides

Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 321
Author(s):  
Maria Orfanoudaki ◽  
Anja Hartmann ◽  
Julia Mayr ◽  
Félix L. Figueroa ◽  
Julia Vega ◽  
...  
Keyword(s):  
Amino Acids ◽  
High Performance Liquid Chromatography ◽  
High Performance ◽  
Red Alga ◽  
Array Detector ◽  
Diode Array ◽  
Diode Array Detector ◽  
The Past ◽  
Specific Species

This study presents the validation of a high-performance liquid chromatography diode array detector (HPLC-DAD) method for the determination of different mycosporine-like amino acids (MAAs) in the red alga Bostrychia scorpioides. The investigated MAAs, named bostrychines, have only been found in this specific species so far. The developed HPLC-DAD method was successfully applied for the quantification of the major MAAs in Bostrychia scorpioides extracts, collected from four different countries in Europe showing only minor differences between the investigated samples. In the past, several Bostrychia spp. have been reported to include cryptic species, and in some cases such as B. calliptera, B. simpliciuscula, and B. moritziana, the polyphyly was supported by differences in their MAA composition. The uniformity in the MAA composition of the investigated B. scorpioides samples is in agreement with the reported monophyly of this Bostrychia sp.

scholarly journals Clitorienolactones and Isoflavonoids of Clitorea ternatea Roots Alleviate Stress-Like Symptoms in a Reserpine-Induced Zebrafish Model

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4137
Author(s):  
Muhammad Afiq Ngadni ◽  
Muhammad Tayyab Akhtar ◽  
Intan Safinar Ismail ◽  
Anis Irfan Norazhar ◽  
Soo Yee Lee ◽  
...  
Keyword(s):  
Mental Illnesses ◽  
Array Detector ◽  
Diode Array ◽  
Root Extract ◽  
Diode Array Detector ◽  
Aqueous Methanol ◽  
Zebrafish Model ◽  
Metabolite Profiles ◽  
Ultrahigh Performance Liquid Chromatography ◽  
As Stress

Clitorea ternatea has been used in Ayurvedic medicine as a brain stimulant to treat mental illnesses and mental functional disorders. In this study, the metabolite profiles of crude C. ternatea root extract (CTRE), ethyl acetate (EA), and 50% aqueous methanol (50% MeOH) fractions were investigated using ultrahigh-performance liquid chromatography–diode array detector–tandem mass spectrometry (UHPLC–DAD–MS/MS), while their effect on the stress-like behavior of zebrafish, pharmacologically induced with reserpine, was investigated. A total of 32 compounds were putatively identified, among which, a series of norneolignans, clitorienolactones, and various flavonoids (flavone, flavonol, isoflavone, and isoflavanone) was found to comprise the major constituents, particularly in the EA and 50% MeOH fractions. The clitorienolactones, presently unique to the species, were present in both the free and glycosylated forms in the roots. Both the EA and 50% MeOH fractions displayed moderate effects on the stress-induced zebrafish model, significantly decreasing freezing duration and elevating the total distance travelled and average velocity, 72 h post-treatment. The results of the present study provide further evidence that the basis for the use of C. ternatea roots in traditional medicine to alleviate brain-related conditions, such as stress and depression, is attributable to the presence of clitorienolactones and the isoflavonoidal constituents.

Sign in / Sign up

Export Citation Format

Share Document