Search results for "Bioanalysis"
showing 10 items of 29 documents
A class-selective immunoassay for simultaneous analysis of anilinopyrimidine fungicides using a rationally designed hapten
2017
he development of multianalyte immunoassays constitutes a main research issue in the field of bioanalytical techniques. In the present study, class-specific antibodies against the three members of the anilinopyrimidine family of fungicides (pyrimethanil, cyprodinil and mepanipyrim) were raised by using a bioconjugate of a rationally designed hapten [5-(6-methyl-2-(phenylamino)pyrimidin-4-yl)pentanoic acid]. Highly sensitive immunoassays were developed for the generic determination of these compounds, using the competitive enzyme-linked immunosorbent assay (ELISA). Particularly, a direct antibody-coated competitive ELISA afforded identical sensitivity for the three anilinopyrimidines, with I…
Enzyme and lateral flow monoclonal antibody-based immunoassays to simultaneously determine spirotetramat and spirotetramat-enol in foodstuffs.
2021
Spirotetramat is employed worldwide to fight insect pests due to its high efficiency. This chemical is quickly metabolized by plants into spirotetramat-enol, so current regulations establish that both compounds must be determined in foodstuffs for monitoring purposes. Nowadays, immunochemical methods constitute rapid and cost-effective strategies for chemical contaminant analysis at trace levels. However, high-affinity binders and suitable bioconjugates are required. In this study, haptens with opposite functionalisation sites were synthesized in order to generate high-affinity monoclonal antibodies. A direct competitive enzyme-linked immunosorbent assay with an IC50 value for the sum of sp…
Application of a low transition temperature mixture for the dispersive liquid–liquid microextraction of illicit drugs from urine samples
2021
© 2021 by the authors.
Smart materials for sample preparation in bioanalysis: A green overview
2021
Abstract The analysis of biological samples is a complex challenge due to the complexity of the matrix, but also to the low concentration of target analytes that must be determined. Consequently, different sample treatment procedures have been proposed in bioanalysis to clean-up and enrich sample extracts, paying special attention to microextraction approaches. In this frame, the combined use of microextraction approaches with smart materials provides environmentally friendly sample treatment strategies with improved selectivity, sensitivity, and reusability. Applications of smart solid materials includes antibody–antigen interaction based materials, aptamers, molecularly imprinted polymers…
Hybrid, multiplexed, functional DNA nanotechnology for bioanalysis
2015
We herein aim to report on the fabrication of DNA nano-heterostructures usable as a robust multi-functional analytical system to obtain multiple and complex data in parallel format from a single sample with unprecedented analytical performances. The ability of chemical information contained in the sequences of programmed DNA structures to organize matter made DNA become a unique material in “the nanoworld”. Such carefully designed DNA nanostructures can then be functionalized/templated with different biomolecules/nanomaterials as different as nanoparticles, nanowires, organic molecules, peptides, and proteins with controlled spacing on the nanometer scale (<10 nm). In this way, it is possib…
Combined heterologies for monoclonal antibody-based immunoanalysis of fluxapyroxad
2018
Nowadays, instrumental methodologies and rapid bioanalytical techniques complement each other for the analysis of toxic chemical compounds. Fluxapyroxad was commercialized a few years ago as a fungicide and today it is being used worldwide to control a variety of pests. In the present study, the development of monoclonal antibody-based immunochemical methods for the analysis of this chemical in food samples was evaluated for the first time. Novel haptens were synthesized and protein bioconjugates were prepared. High-affinity and specific monoclonal antibodies to fluxapyroxad were generated from two haptens with alternative linker tethering sites. Haptens with linker site heterology and a st…
Molecularly Imprinted Polymers as Useful Sorbents for Bioanalysis
2022
The determination of various active compounds in different types of biological samples attracts recently considerable attention. Unfortunately, the complexity of such sample matrices requires the application of multistage analytical procedures, which by many analysts is considered the most critical step in the whole analytical process. Sample preparation techniques dedicated to bioanalysis must ensure effective isolation and enrichment of various, often trace, amounts of analytes. Furthermore, the high selectivity of extraction of the target analytes, in relation to other interfering substances co-presented in the sample, is important in this case. Therefore, over the last two decades, the …
Partial least squares attenuated total reflectance IR spectroscopy versus chromatography: the greener method
2012
Method election is a complex task that must be done carefully in order to ensure the capability of analytical methodologies to provide appropriate data for problem solving. This is a real challenge in all fields, but especially with bioanalysis, which in many cases involves the need to do a large number of determinations in complex
Bioanalysis of digoxin and its metabolites using direct serum injection combined with liquid chromatography and on-line immunochemical detection.
1994
Abstract An automated dual-column liquid chromatographic assay for digoxin is described. Serum samples are directly injected onto a restricted-access solid-phase extraction support. After liquid chromatographic (LC) separation on a C18 analytical column, antigenic analytes are detected by means of post-column immunochemical detection (ICD) using fluorescein-labelled antibodies against digoxigenin. The detection limit of this assay is 160 pg/ml (preconcentration of 1.0 ml serum). With the present method digoxin and three of its cross-reactive metabolites were determined in serum taken from patients which were orally administered a 1-mg dose of digoxin. The results obtained with LC—ICD were c…
Validating quantitative PCR assays for cell-free DNA detection without DNA extraction: Exercise induced kinetics in systemic lupus erythematosus pati…
2021
ABSTRACTCirculating cell-free DNA (cfDNA) has been investigated as a screening tool for many diseases. To avoid expensive and time-consuming DNA isolation, direct quantification PCR assays can be established. However, rigorous validation is required to provide reliable data in the clinical and non-clinical context. Considering International Organization for Standardization, as well as bioanalytical method validation guidelines we provide a comprehensive procedure to validate assays for cfDNA quantification from unpurified blood plasma. A 90 and 222 bp assay was validated to study the kinetics of cfDNA after exercise in patients with systemic lupus erythematosus. The assays showed ultra-low …