scholarly journals Dual 2-Hydroxypropyl-β-Cyclodextrin and 5,10,15,20-Tetrakis (4-Hydroxyphenyl) Porphyrin System as a Novel Chiral-Achiral Selector Complex for Enantioseparation of Aminoalkanol Derivatives with Anticancer Activity in Capillary Electrophoresis

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 993
Author(s):  
Błażej Grodner ◽  
Mariola Napiórkowska
Keyword(s):  
Capillary Electrophoresis ◽  
Anticancer Agents ◽  
Chiral Discrimination ◽  
Combined Effects ◽  
Pilot Studies ◽  
Repeatability And Reproducibility ◽  
The Stability ◽  
Short Time ◽  
High Separation

In this study, a complex consisting of 2-hydroxypropyl-β-cyclodextrin and 5,10,15,20-tetrakis (4-hydroxyphenyl) porphyrin, (named dual chiral-achiral selector complex) was used for the determination of two novel potential anticancer agents of (I) and (II) aminoalkanol derivatives. This work aimed at developing an effective method that can be utilized for the determination of I (S), I (R), and II (S) and II (R) enantiomers of (I) and (II) compounds through the use of a dual chiral-achiral selector complex consisting of hydroxypropyl-β-cyclodextrin and 5,10,15,20-tetrakis (4-hydroxyphenyl) porphyrin system by applying capillary electrophoresis. This combination proved to be beneficial in achieving high separation selectivity due to the combined effects of different modes of chiral discrimination. The enantiomers of (I) and (II) compounds were separated within a very short time of 3.6–7.2 min, in pH 2.5 phosphate buffer containing 2-hydroxypropyl-β-cyclodextrin and 5,10,15,20-tetrakis (4-hydroxyphenyl) porphyrin system at a concentration of 5 and 10 mM, respectively, at 25 °C and +10 kV. The detection wavelength of the detector was set at 200 nm. The LOD for I (S), I (R), II (S), and II (R) was 65.2, 65.6, 65.1, and 65.7 ng/mL, respectively. LOQ for I (S), I (R), II (S), and II (R) was 216.5, 217.8, 217.1, and 218.1 ng/mL, respectively. Recovery was 94.9–99.9%. The repeatability and reproducibility of the method based on the values of the migration time, and the area under the peak was 0.3–2.9% RSD. The stability of the method was determined at 0.1–4.9% RSD. The developed method was used in the pilot studies for determining the enantiomers I (S), I (R), II (S), and II (R) in the blood serum.

Simultaneous determination of whitening agents and parabens in cosmetic products by capillary electrophoresis with on-line sweeping enhancement

2014 ◽  
Vol 6 (19) ◽  
pp. 7615-7620 ◽  
Author(s):  
I-Chi Tsai ◽  
Chia-Yu Su ◽  
Cho-Chun Hu ◽  
Tai-Chia Chiu
Keyword(s):  
Capillary Electrophoresis ◽  
Simultaneous Determination ◽  
Separation Efficiency ◽  
Analysis Time ◽  
Cosmetic Products ◽  
Short Analysis Time ◽  
On Line ◽  
High Separation

An on-line sweeping-MEKC method for simultaneous determination of whitening agents and parabens in commercial cosmetic products was demonstrated. This approach was shown to offer high separation efficiency, short analysis time, and convenience of analysis. The LODs of the analytes were in the range from 8 to 162 nM (1.1 to 21.0 ng mL−1) and a 46 to 279-fold enhancement was achieved.

scholarly journals Poly (Adenine) Modified Graphene-Based Voltammetric Sensor for the Electrochemical Determination of Catechol, Hydroquinone and Resorcinol

2020 ◽  
Vol 14 (1) ◽  
pp. 52-62 ◽  
Author(s):  
Jamballi G. Manjunatha
Keyword(s):  
Differential Pulse ◽  
Electrochemical Determination ◽  
Repeatability And Reproducibility ◽  
Pulse Voltammetry ◽  
The Stability ◽  
Graphene Paste Electrode ◽  
Modified Graphene ◽  
Paste Electrode ◽  
Voltammetric Technique

Objective: This paper presents the application of Poly (Adenine) Modified Graphene Paste Electrode (PAMGPE) for the analysis of Catechol (CC) with Resorcinol (RC) and Hydroquinone (HQ) by a voltammetric technique. Methods: Electropolymerization technique was utilized for the modification of the sensor surface. The electrode surface was characterized by Field Emission Scanning Electron Microscopy (FE-SEM). Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV) were used to study the redox behavior of CC, RC and HQ. Results: Oxidation peak current of CC increased linearly with the concentration of CC in the range from 2×10-6- 8×10-6 M and 1×10-5-1.5 ×10-4 M with a detection limit of 2.4×10-7 M. The practical application of the developed sensor was verified as exact for the determination of CC in water sample. Conclusion: The stability, repeatability, and reproducibility of the developed electrode were studied and established good characteristics. Furthermore, the PAMGPE was examined for the simultaneous determination of CC, RC and HQ.

scholarly journals Microassay of amiodarone and desethylamiodarone in serum by capillary electrophoresis with head-column field-amplified sample stacking

1996 ◽  
Vol 42 (11) ◽  
pp. 1805-1811 ◽  
Author(s):  
C X Zhang ◽  
Y Aebi ◽  
W Thormann
Keyword(s):  
Capillary Electrophoresis ◽  
Detection Limit ◽  
Linear Response ◽  
Separation Efficiency ◽  
Operating Costs ◽  
Serum Samples ◽  
Sample Stacking ◽  
Liquid Handling ◽  
High Separation

Abstract Binary-system capillary electrophoresis (CE) with head-column field-amplified sample stacking permits determination of amiodarone and desethylamiodarone in 20-microL serum samples. The assay is characterized by a detection limit for both compounds of 80 nmol/L and by excellent linear response over the recommended therapeutic range for amiodarone (1.5-4 mumol/L). Intra- and interday reproducibilities (CVs) between 3% and 6% and run times of approximately 10 min are comparable with those for conventional HPLC. Besides excellent sensitivity, attractive features of the assay include low operating costs, high separation efficiency, rapid drug extraction, consumption of almost negligible amounts of organic solvents, and simple operation. If appropriate microvessels and liquid-handling facilities are available, the same assay can be performed with 2 microL of serum, and if the serum is not diluted but rather is concentrated during extraction, < 1 nmol/L of amiodarone can be detected.

Determination of the stability constants of Pu(VI) carbonate complexes by capillary electrophoresis coupled with inductively coupled plasma mass spectrometer

2018 ◽  
Vol 106 (10) ◽  
pp. 801-807 ◽  
Author(s):  
Jean-Charles Alexandre ◽  
Nicolas Dacheux ◽  
Jean Aupiais
Keyword(s):  
Capillary Electrophoresis ◽  
Stability Constants ◽  
Inductively Coupled Plasma ◽  
Chemical System ◽  
Interaction Coefficients ◽  
Inductively Coupled ◽  
Icp Ms ◽  
The Stability ◽  
Carbonate Complexes

Abstract New determination of the stability constants related to the Pu(VI)/carbonate chemical system has been obtained by coupling capillary electrophoresis and ICP-MS at the ionic strength of 0.202 m in NaClO4 and for a temperature of 25°C. The following values have been obtained: ${\log _{10}}{\beta _{{\rm{Pu}}{{\rm{O}}_2}{\rm{C}}{{\rm{O}}_3}}} = 8.12 \pm 0.02,$ ${\log _{10}}{\beta _{{\rm{Pu}}{{\rm{O}}_2}({\rm{C}}{{\rm{O}}_3})_2^{2 - }}} = 13.96 \pm 0.04,$ and ${\log _{10}}{\beta _{{\rm{Pu}}{{\rm{O}}_2}({\rm{C}}{{\rm{O}}_3})_3^{4 - }}} = 18.10 \pm 0.03.$ Based on the values selected by AEN/OECD, the interaction coefficients have been re-evaluated as follows: ${\varepsilon _{{\rm{Pu}}{{\rm{O}}_2}{\rm{C}}{{\rm{O}}_3}}} = 0.02 \pm 0.21,$ ${\varepsilon _{{\rm{Pu}}{{\rm{O}}_2}({\rm{C}}{{\rm{O}}_3})_2^{2 - },{\rm{N}}{{\rm{a}}^ + }}} = 0.12 \pm 0.08,$ ${\varepsilon _{{\rm{Pu}}{{\rm{O}}_2}({\rm{C}}{{\rm{O}}_3})_3^{4 - },{\rm{N}}{{\rm{a}}^ + }}} = 0.14 \pm 0.18{\rm{ kg}} \cdot {\rm{mo}}{{\rm{l}}^{ - 1}}.$

scholarly journals A method of analysing galvanometer records

1921 ◽  
Vol 99 (697) ◽  
pp. 172-174 ◽  
Keyword(s):  
Accurate Determination ◽  
Combined Effects ◽  
Control Curve ◽  
Electric Current Passing ◽  
Constant Coefficients ◽  
Linear Differential ◽  
Short Time ◽  
And Control ◽  
Differential And Integral Equations

In recent papers, we have described experiments in which photographic records were made of the deflection of a sensitive galvanometer registering the rise of temperature of a muscle (or other substance) resting on a thermopile. The system is a complicated one, involving the inertia, damping and control of the moving system of the galvanometer, and the heat conductivity and capacity both of the substance on the thermopile, and of the material of the thermopile itself; consequently the accurate determination of the course of the production of heat in the substance on the thermopile, from the photographic record of the galvanometer deflection, would appear to require the solution of complicated differential and integral equations, with a large number of constants to be determined by observation. To avoid this necessity we adopted a procedure in which a given amount of heat was liberated, practically instantaneously, by a powerful electric current passing for a short time through the substance on the thermopile, and the resulting deflection recorded photographically. This record, which we will call the “control curve,” involves all the constants of the system, and may be used (according to the procedure described below), for the determination of the course of the heat-production in general. The motion of the moving system of a sensitive galvanometer (assumed completely damped) is governed by linear differential equations with constant coefficients, as also is the flow of heat from substance to thermopile, and in the thermopile itself. Consequently if a deflection of the galvanometer following the course y = δH f ( t ), be given by heat δ'H liberated at time 0, a deflection y' = δ'H f ( t-θ ) will be given by heat δ'H liberated at time θ , and a deflection y + y' = δH f ( t ) + δ'H f ( t-θ ) by the combined effects of heat δH at time 0 and of heat δ'H at time θ . In making the “control curve” we have determined experimentally the form of the function f in equation (1), and if we know the form of the function ϕ in the equation H = ϕ ( θ ), where H is heat, and θ is time, we can at once compute the deflection at time t from the equation y = ∫ θ = 0 θ = t dϕ / dθ f ( t-θ ) dθ = Ψ( t )(say).

scholarly journals Stability of tris-1,10 - phenanthroline iron (II) complex in different composites

2010 ◽  
Vol 16 (2) ◽  
pp. 193-198 ◽  
Author(s):  
Dragica Lazic ◽  
Branko Skundric ◽  
Jelena Penavin-Skundric ◽  
Slavica Sladojevic ◽  
Ljubica Vasiljevic ◽  
...  
Keyword(s):  
Total Iron ◽  
Time Interval ◽  
Short Time Interval ◽  
Time Period ◽  
Huge Impact ◽  
Limited Application ◽  
The Stability ◽  
Short Time ◽  
Composite Samples

The composition of composites has a huge impact on the stability of tris-1, 10 - phenanthroline iron (II) complex during the determination of total iron. The subject of this work is determination the stability of tris-1, 10 - phenanthroline iron (II) complex in different composites. Composites with different concentration in which total iron was determined were alumina and zeolite. Stability of this complex was monitored in a time period of 0-60 min. The aim of this work is to determine the concentration of different composite samples and the time interval in which the stability of the complex is the highest. The spectrophotometric method was used for the determination. The tris-1, 10 - phenanthroline iron (II) complex with alumina is more stable at higher concentration of the samples. With zeolite, however, this complex is stable in a short time interval, regardless of the concentration of the sample. This conclusion indicates on increase of absorption, which is a consequence of impede complex formation and creating a new complex. For this reason, this method has only a limited application.

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