Horseradish peroxidase (HRP) encapsulated in liposomes was directly detected by using luminol chemiluminescence (CL) with H2O2 without lysis of liposomes. At a low concentration of H2O2, the initial rate of HRP-catalyzed luminol CL in liposomes was slower than that of HRP-catalyzed luminol CL in a lipid-free bulk solution. The decrease in the initial rate of the CL reaction in liposomes was due to the membrane permeation of luminol and H2O2. At a high concentration of H2O2, the initial rate of the CL reaction in liposomes was the same as that in a lipid-free bulk solution. The CL measurement conditions in both a lipid-free bulk solution and in liposomes were optimized in the concentrations of luminol and H2O2 by measuring the CL response curves, in which only one peak appeared and the CL intensity was maximal. The CL intensity observed in HRP-catalyzed luminol CL in liposomes was a factor of seven greater than that observed in a lipid-free bulk solution. The CL intensity was dependent on the amount of HRP-encapsulated liposomes used. The detection limit in the direct detection of HRP encapsulated in liposomes was sensitive by a factor of 3 compared with that in HRP-catalyzed luminol CL in a lipid-free bulk solution.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.2116/analsci.24.477 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Mathematical lipid correction of δ13C and effect of lipid extraction on δ15N of European eel (Anguilla anguilla) muscle: Lipid correction of δ13C in European eels.
Rapid Commun Mass Spectrom
December 2024
MARBEC, Université de Montpellier, CNRS, Ifremer, IRD, INRAE, Sète, France.
Rationale: Carbon (δC) and nitrogen (δN) stable isotope analysis is a powerful tool to investigate diverse questions in fish ecology, such as their trophic position or migration strategies. These questions appear particularly important to protect endangered European eel. However, elevated lipid content in eel muscle can bias δC values, as lipids are C-depleted compared to proteins and carbohydrates.
View Article and Find Full Text PDFLipid-correction models for δC values across small pelagic fishes (Clupeiformes) from the Atlantic Ocean.
Mar Environ Res
November 2023
IRD, Univ Brest, CNRS, Ifremer, LEMAR, F-29280, Plouzané, France.
The interpretation of δC values in trophic ecology requires standardization of the lipid content of organisms estimated through their C:N ratio. To avoid time-consuming lipid extractions, the use of mathematical corrections has been developed for many years, and the conclusions generally point in the direction of species-specific adjustment of the models. This study aimed at defining the maximum taxonomic level required to obtain the best corrected δC values in small pelagic fish of the order Clupeiformes.
View Article and Find Full Text PDFLipid-extracted muscle and liver tissues: Can they reveal mercury exposure of pelagic sharks?
Chemosphere
November 2023
College of Marine Sciences, Shanghai Ocean University, Shanghai, China; Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai, China; National Engineering Research Centre for Oceanic Fisheries, Shanghai Ocean University, Shanghai, China; Key Laboratory of Oceanic Fisheries Exploration, Ministry of Agriculture and Rural Affairs, Shanghai, China. Electronic address:
Pelagic sharks are apex predators in oceanic ecosystems and tend to accumulate high amounts of mercury (Hg). The conventional method for assessing Hg exposure in sharks involves analyzing tissue samples without any chemical treatment. However, a substantial number of chemically treated tissue samples are still being preserved in laboratories or museums.
View Article and Find Full Text PDFUsing stable isotope (δC, δN) values from feces and breath to infer shorebird diets.
Oecologia
October 2022
Department of Biology, University of Western Ontario, London, ON, N6A 5B7, Canada.
The use of stable isotopes of carbon (δC) and nitrogen (δN) from feces and breath offers potential as non-destructive tools to assess diets and nutrition. How stable isotope values derived from breath and feces compare with those from commonly used tissues, such as blood fractions and liver, remains uncertain, including understanding the metabolic routing of dietary nutrients. Here, we measured δC and δN from feces and δC of breath from captive Red-necked Stints (Calidris ruficollis) and 26 species of wild-caught migratory shorebirds (n = 259 individuals) and compared them against isotopic values from blood and feathers.
View Article and Find Full Text PDFConformational flexibility of apolipoprotein A-I amino- and carboxy-termini is necessary for lipid binding but not cholesterol efflux.
J Lipid Res
March 2022
Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, OH, USA. Electronic address:
Because of its critical role in HDL formation, significant efforts have been devoted to studying apolipoprotein A-I (APOA1) structural transitions in response to lipid binding. To assess the requirements for the conformational freedom of its termini during HDL particle formation, we generated three dimeric APOA1 molecules with their termini covalently joined in different combinations. The dimeric (d)-APOA1C-N mutant coupled the C-terminus of one APOA1 molecule to the N-terminus of a second with a short alanine linker, whereas the d-APOA1C-C and d-APOA1N-N mutants coupled the C-termini and the N-termini of two APOA1 molecules, respectively, using introduced cysteine residues to form disulfide linkages.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!