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The determination of curcumin (CM), the active ingredient of turmeric, can be used to control the quality of turmeric rhizomes and products. A CM sensor was developed based on a nitrogen and sulfur dual-doped laser-induced graphene (N-S@LIG) material fabricated in the form of a three-electrode system on a polyethylene terephthalate (PET) substrate. N-S@LIG was synthesized by the one-step laser ablation of a polyimide (PI) carbon source coated with a methylene blue (MB) N and S source. The surface morphology of the fabricated electrode was studied by scanning electron microscopy, energy dispersive x-ray analysis, Raman spectroscopy, contact angle analysis, and X-ray photoelectron spectroscopy. The electrode showed an excellent electron transfer ability and good electrocatalytic performances for the detection of CM. The N and S dual-doped laser-induced graphene electrode (N-S@LIGE) was employed to determine CM by differential pulse adsorptive stripping voltammetry (DPAdSV). To enable on-site analysis of CM in turmeric samples, the N-S@LIGE was incorporated with a small potentiostat plugged into a smartphone to manage the measurements and to display results. The developed CM sensor displayed a linear determination range from 0.10 to 30 μmol L -1 , a detection limit of 0.036 μmol L -1 , good repeatability, reproducibility and anti-interference properties. The developed CM sensor was used to measure CM in cultivated rhizomes and commercial turmeric powder. The analysis results correlated well with the results from the standard spectrophotometric analysis and high-performance liquid chromatography., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

This study aims to analyze the neutralization ability against Omicron parental variants in five clusters of individuals with different Coronavirus disease (COVID-19) immunity backgrounds, including individuals receiving a homologous or heterologous vaccine without prior infection, recovered patients with homologous or heterologous vaccination, and recovery patients without vaccination. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surrogate virus neutralization assay was performed on serum samples. Spearman correlation analysis showed that the percent inhibition against Omicron B.1.1.529 and BA.2 was significantly related to the period of serum collection ( r = 0.730 and 0.787, p < 0.001, respectively). Very strong correlation between percent inhibition of neutralizing antibody against Omicron B.1.1.529 and BA.2 variants ( r s = 0.973, p < 0.001) was also observed. The neutralizing activity of the sera from recovery patients receiving homologous and heterologous vaccine against the wild-type, B.1.1.529, and BA.2 Omicron variants was significantly higher ( p < 0.001) than that of recovery patients without vaccination. This study robustly showed that the breakthrough SARS-CoV-2 Omicron variant in individuals who received homologous and heterologous vaccines had a high level of neutralizing activity against B.1.1.529 and BA.2 parental lineage of XBB subvariants. Therefore, the next-generation COVID-19 vaccine against emerging variants is needed to improve resilience against ongoing variants, particularly for persons who have never been infected.