Search results for "Analytical technique"
showing 10 items of 34 documents
Green solvents and Ultrasound-Assisted Extraction of bioactive orange (Citrus sinensis) peel compounds.
2019
AbstractByproducts such as orange peel have potential uses because of their bioactive compounds, which are important for their potential to reduce the risk factors of diseases caused by aging. The lack of effective techniques and the high levels of pollution produced by the conventional extraction of bioactive compounds using organic solvents have highlighted the need to enhance the ‘green chemistry’ trend. This study evaluates the use of ultrasound to extract bioactive compounds from orange peel. The antioxidant capacity, phenolic content, ascorbic acid, total carotenoids, and HPLC profile of phenolic compounds from orange peel extracts were obtained by a physicochemical evaluation. The re…
Application of LA-ICP-MS as a rapid tool for analysis of elemental impurities in active pharmaceutical ingredients.
2014
The control of inorganic contaminants in active pharmaceutical ingredients has a significant role in the quality control of drug products. The concentration limits for metal residues in drug products have been defined by various regulatory guidelines. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is a powerful and fast analytical technique for multi-elemental analysis. A disadvantage in using LA-ICP-MS method is the lack of matrix reference materials for validation and calibration purposes. This article focuses on the handling strategy of laboratory-made matrix calibration standards for the quantification of elemental impurities in an active pharmaceutical ingredie…
Crowdsourced analysis of fungal growth and branching on microfluidic platforms
2021
Fungal hyphal growth and branching are essential traits that allow fungi to spread and proliferate in many environments. This sustained growth is essential for a myriad of applications in health, agriculture, and industry. However, comparisons between different fungi are difficult in the absence of standardized metrics. Here, we used a microfluidic device featuring four different maze patterns to compare the growth velocity and branching frequency of fourteen filamentous fungi. These measurements result from the collective work of several labs in the form of a competition named the “Fungus Olympics.” The competing fungi included five ascomycete species (ten strains total), two basidiomycete…
The ways to the trace level analysis in infrared spectroscopy
2020
The future of infrared (IR) spectroscopy as an analytical technique is assured due to its versatility and its numerous advantages; such as the possibility to obtain molecular specific information for virtually any sample in any state with no treatment or minimal sample preparation. However, spectroscopists are not satisfied with relegating IR spectroscopy just to major and minor component analysis and have been looking at analysis at the trace level too. This review is the recognition of the brilliant research performed during the past two decades and the advances achieved in this area, which have made possible the analysis of contaminants at parts per billion (ppb) levels by IR in differen…
Detection and characterization of emerging psychoactive substances by ion mobility spectrometry
2014
Rapid detection and identification of novel psychoactive substances (NPS) continues to present significant analytical challenges to forensic and analytical chemists. Ion mobility spectrometry (IMS) has been traditionally considered as the analytical technique of choice to detect illicit drugs in security points in airports, borderlines and customs. Databases of the reduced mobility (K0 ) values of illicit drugs are available in the scientific literature and they should be completed with data of emerging designer drugs. In this paper, we have evaluated the effect of different measurement conditions and determined the K0 values of an important number of NPS including different families; such …
A New Simple Static Method for the Determination of Solubilities of Condensed Compounds in Supercritical Fluids
2002
Abstract A simple static method based on gravimetric measurements has been adopted to measure the solubility of benzenecarboxylic acid, 2-hydroxy-benzenecarboxylic acid, 4-hydroxy-benzenecarboxylic acid and 1,8-dihydroxyanthraquinone along several isotherms in the temperature range 318–357 K and the pressure interval 7–23 MPa. Solubility data have been correlated with the Zieger–Eckert approach, using the Fedor atomic and group contribution method to estimate the solubility parameter and the molar volume of the solutes. A good agreement was obtained between data reported in the literature and those determined using the proposed method which allows one to measure solubility mole fraction as …
Sample preparation methods for the determination of pesticides in foods using CE-UV/MS.
2010
Much progress has been made in pesticide analysis over the past decade, during this time hyphenated techniques involving highly efficient separation with sensitive detection have become the techniques of choice. Among these, methods based on separation with mass spectrometric detection have resulted in greater likelihood of identification and are acknowledged to be extremely useful and authoritative methods for the determination of pesticide residues but the inherent advantages of the use of CE as a separation technique are well-known and can be summarized as high separation efficiency, low analysis time, high resolution power, and low consumption of samples and reagents. Although UV is the…
Recent trends in liquid chromatography-tandem mass spectrometry to determine pesticides and their metabolites in food
2007
Abstract The applications of liquid chromatography-mass spectrometry (LC-MS) have exploded in innumerable analytical fields, including pesticide-residue determination. There is no doubt that LC-MS is currently competing with gas chromatography (GC)-MS for the status of ‘reference’ analytical technique to determine pesticide residues and that its ever-increasing application is bound to the evolution of modern instruments and their growing performance qualities. We highlight the large number and variety of pesticides that can be readily determined using such instruments, the respective merits of the different mass analyzers, and the improvements brought about by tandem MS (MS 2 ). We also dis…
Sample Preparation to Determine Pharmaceutical and Personal Care Products in an All-Water Matrix: Solid Phase Extraction
2020
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Stochastic fluctuations of bosonic dark matter
2021
Numerous theories extending beyond the standard model of particle physics predict the existence of bosons that could constitute the dark matter (DM) permeating the universe. In the standard halo model (SHM) of galactic dark matter the velocity distribution of the bosonic DM field defines a characteristic coherence time $\tau_c$. Until recently, laboratory experiments searching for bosonic DM fields have been in the regime where the measurement time $T$ significantly exceeds $\tau_c$, so null results have been interpreted as constraints on the coupling of bosonic DM to standard model particles with a bosonic DM field amplitude $\Phi_0$ fixed by the average local DM density. However, motivate…