105 research outputs found
How to measure greenness? : metrics in green chemistry
The presentation delves into the metrics used to assess the "greenness" of chemical procedures and processes, categorizing them into two primary segments. The first, "Simple Greenness Indicators", are quantitative parameters derived from empirical or estimated data, offering insights into environmental impacts such as waste generation, energy consumption, or hazardous substance involvement. Especially, the Chlortox scale is introduced as a significant metric to gauge the toxicity of substances. The second segment encompasses "Models", intricate tools providing a holistic view of greenness by considering multiple criteria. Notable models include the Green Analytical Procedures Index (GAPI), its complex variant ComplexGAPI, the Analytical GREEnness metric approach (AGREE), and AGREEprep, which focuses on sample preparation. The RGB model stands out, with Red representing performance, Green symbolizing sustainability, and Blue indicating practical and economic criteria. This presentation serves as a valuable resource for academic teachers, offering a structured approach to seamlessly integrate the metrics of green chemistry into the curriculum, thereby fostering a deeper understanding and commitment to sustainable practices in the next generation of chemists
Capillary electrophoresis screening method for six tri-cyclic antidepressants in human serum
A capillary electrophoretic (CE) method for screening of six tricyclic antidepressants: amitriptyline,
nortriptyline, imipramine, desipramine, doxepin and nordoxepin, in human serum, has been developed. The
drugs were separated in a bare fused silica capillary (50 μm i.d.) using the background electrolyte: 50 mM
CAPSO (pH 9.54) in methanol/water with KCl addition. For increasing the method sensitivity, the sample con-
centration in the capillary (sample stacking) using pressure and electrokinetic injection has been applied. The
standard addition method was used for calibration of the developed analytical procedure. The precision of the
identification parameter (the relative migration time) and the quantitative parameter (the relative peak area) was
within the range of 0.05ñ1.65 and 0.73ñ6.7 (RSD %), respectively. The detection limits were found to be 30
ng/mL for desipramine, 62.5 ng/mL for nortriptyline, and 50 ng/mL for remaining analytes
Quantitative insight into PCA formation following different chlorhexidine activation methods in endodontic treatment
The chemistry and histology of sexually dimorphic mental glands in the freshwater turtle, Mauremys leprosa
Enhancing effectiveness of capillary electrophoresis as an analytical tool in the supramolecular acidity modification
Carbon footprint of the analytical laboratory and the three-dimensional approach to its reduction
What is the carbon footprint of a common HPLC instrument per one measurement? How much will it increase when we use a mass detector instead of a spectrophotometer? What is the carbon footprint of an average laboratory in comparison to a household, petrol and electric cars, and group of people breathing simultaneously? How much do these results depend on the specifics of energy production in a given country? Is it possible to ensure the carbon neutrality of an advanced analytical method by using dedicated solar and wind farms? How large infrastructure is needed to supply the entire laboratory with green energy? What are the most reasonable activities which should be realized in the near future to reduce the environmental impact of analytical laboratories? This article attempts to answer these questions. The predictions are based on the simple measurements of the electricity consumption for selected laboratory instruments (separation techniques) and the commonly available statistical reports. The presented outcomes allow to imagine the magnitude of laboratory-related emissions. A future perspective is shown and discussed, embracing the three-dimensional space of possible efforts and the inclusion of energy consumption and associated carbon footprint as a mandatory validation criterion of new analytical methods
Identification and determination of ergot alkaloids in Morning Glory cultivars
Seeds of plants from Ipomoea genera contain numerous ergot alkaloids, including psychoactive ergine and ergometrine, and are often abused as so-called “legal highs.” In this work, an analytical method for determination of ergine and ergometrine, and identification of other alkaloids was developed, optimized, and validated. Three extraction techniques, ultrasound-assisted extraction in bath, or with sonotrode, and microwave-assisted extraction were evaluated, and it was concluded that ultrasonic bath is the most suitable technique for extraction of ergot alkaloids. The extraction method was later optimized using a Doehlert experimental design with response surface methodology and used together with the optimized LC-Q-TOF-MS method. The analytical procedure was validated in terms of recovery and matrix effect, repeatability, and intermediate precision. Limits of detection and quantification were 1.0 and 3.0 ng mL(–1), respectively, and were sufficient for determination of ergot alkaloids in Ipomoea seeds. The analysis revealed that from five kinds of seeds purchased from different vendors, only three contained ergot alkaloids. Concentration of alkaloids and their relative abundance was similar in samples representative for whole seeds packs; however, when single seeds were analyzed, significant discrepancies in ergine and ergometrine concentrations were detected. [Figure: see text] ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00216-016-9322-5) contains supplementary material, which is available to authorized users
Influence of pH measurement inaccuracy on the values of acidity constant determined on the basis of electrophoretic and thermophoretic data
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