Search results for "analytical procedures"
showing 6 items of 26 documents
Sample preparation strategies for the determination of psychoactive substances in biological fluids
2020
This review focuses on the existing analytical procedures for the determination of new psychoactive substances (NPS) in biological fluids by chromatographic methods. Direct analysis of samples is scarcely employed and most proposed methodologies include a sample pre-treatment in order to remove matrix interferents and, in some cases, pre-concentrate extracts. Current extraction methods for NPS determination in plasma/serum, urine, and oral fluids have been widely discussed, such as liquid-liquid, solid-phase, and micro extraction approaches, highlighting the advantages and drawbacks of the proposed extraction methodologies. Regarding microextraction approaches, techniques like microextracti…
Multivariate Assessment of Procedures for Molecularly Imprinted Polymer Synthesis for Pesticides Determination in Environmental and Agricultural Samp…
2021
In the case of quantitative and qualitative analysis of pesticides in environmental and food samples, it is required to perform a sample pre-treatment process. It allows to minimalize the impact of interferences on the final results, as well as increase the recovery rate. Nowadays, apart from routinely employed sample preparation techniques such as solid-phase extraction (SPE) or solid-phase microextraction (SPME), the application of molecularly imprinted polymers (MIPs) is gaining greater popularity. It is mainly related to their physicochemical properties, sorption capacity and selectivity, thermo-mechanical resistance, as well as a wide range of polymerization techniques allowing to obta…
Micellar liquid chromatography in doping control.
2010
The issue of doping control in sport involves the development of reliable analytical procedures and efficient strategies to process a large number of samples in a short period of time. Reversed-phase LC techniques with aqueous–organic mobile phases and MS or diode-array detection yield satisfactory results for the identification of prohibited substances in sport. However, time-consuming sample pretreatment steps are required, which reduces sample throughput. Micellar LC (MLC) that uses hybrid mobile phases of surfactant above its critical micellar concentration and organic solvent has been revealed as an interesting alternative. The surfactant sodium dodecyl sulfate solubilizes the protein…
Analytical characteristics, applications and perspectives in thermal lens spectrometry
1993
Abstract The following selected aspects of thermal lens spectrometry are briefly outlined: fundamentals, sensitivity and background noise, detection approaches, flowing samples, multi-wavelength experiments, thermal lens circular dichroism, associated colateral phenomena and physico-chemical applications and requirements of analytical procedures. The state-of-the-art and problems encountered are discussed.
Determination of sorption properties of heavy metals in various biosorbents
2018
Various techniques of determination of properties of physicochemical processes of heavy metal sorption in biosorbents were analysed. The methods of preparing and storing samples, conditions of experiment performance, as well as the methods of data interpretation were discussed. Two procedures of study were analysed: (1) in the static system of biosorbent-solution contact and (2) in the system of dynamic flow of solution. Copper cation sorption was studied. The effect of consecutive stages of the study on the quality of final results was shown. A high degree of uncertainty of the sorption capacity assessment was reported, which was dependent on the manner of conducting the study. The applica…
ANALYTICAL PROCEDURES FOR THE DETERMINATION OF TRACE AMOUNTS OF XENOBIOTICS IN ENVIRONMENTAL WATER SAMPLES
2016
Wciąż wzrastające zanieczyszczenie środowiska związane z działalnością człowieka stanowi poważny problem ekologiczny współczesnego świata. Ksenobiotyki to substancje obce i potencjalnie szkodliwe dla organizmów żywych. Obecność niektórych z nich w środowisku wodnym może nieść za sobą poważne konsekwencje. Do najbardziej niebezpiecznych należą antybiotyki oraz pestycydy. Rozwój nauki i techniki umożliwił kontrolowanie tych substancji w środowisku naturalnym. Oznaczanie śladowych ilości ksenobiotyków w próbkach wód środowiskowych jest złożonym procesem, wymagającym zastosowania odpowiedniej metody ekstrakcyjnej i analitycznej. Złożoność matrycy oraz obecność substancji współobecnych stanowi d…