The contamination of freshwater with microplastics (MPs) has been established globally. While the analysis of MPs has predominantly involved spectroscopic methods for revealing particle numbers, the potential of employing spectroscopy for mass estimation has been underutilized. Consequently, there is a need to enhance our understanding of the mass loads of MPs and ensure the complementarity and comparability of various techniques for accurate quantification. This study presents the first comparative results on urban water samples using micro Fourier-transform infrared (μ-FTIR) imaging and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) to identify and quantify MPs in both particle numbers and mass concentration. Two sampling campaigns in summer and winter were conducted at 11 locations within the Amsterdam canal network. An advanced in-situ volume-reducing sampling pump was employed to collect MPs from the surface water within the size fraction of 10-300 μm. The analysis revealed MP concentrations within the range of 16-107 MP/m, estimated to be 2.0-789 μg/m by μ-FTIR imaging and 8.5-754 μg/m by Py-GC-MS. The results of the two analysis techniques showed good comparability in terms of the general trends of MP abundances, with variations in polymer compositions due to the inherent inter-methodological differences. Elevated MP concentrations were observed in the city center compared to the suburban areas. In addition, seasonal differences in MP abundances were noted at the locations with high human activity.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.envpol.2024.124088 | DOI Listing |
Nanotoxicology
January 2025
Infection, Inflammation and Repair, Faculty of Medicine, University of Southampton, Southampton, UK.
The role of surfactant proteins A and D (SP-A and SP-D) in lung clearance and translocation to secondary organs of inhaled nanoparticles was investigated by exposing SP-A and SP-D knockout (AKO and DKO) and wild type (WT) mice nose-only for 3 hours to an aerosol of 20 nm gold nanoparticles (AuNPs). Animals were euthanised at 0-, 1-, 7- and 28-days post-exposure. Analysis by inductively coupled plasma mass spectrometry (ICP-MS) of the liver and kidneys showed that extrapulmonary translocation was below the limits of detection.
View Article and Find Full Text PDFAnal Chem
January 2025
State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China.
Timely and accurate detection of trace mycotoxins in agricultural products and food is significant for ensuring food safety and public health. Herein, a deep learning-assisted and entropy-driven catalysis (EDC)-Argonaute powered fluorescence single-particle aptasensing platform was developed for ultrasensitive detection of fumonisin B (FB) using single-stranded DNA modified with biotin and red fluorescence-encoded microspheres as a signal probe and streptavidin-conjugated magnetic beads as separation carriers. The binding of aptamer with FB releases the trigger sequence to mediate EDC cycle to produce numerous 5'-phosphorylated output sequences, which can be used as the guide DNA to activate downstream Argonaute (Ago) for cleaving the signal probe, resulting in increased number of fluorescence microspheres remaining in the final reaction supernatant after magnetic separation.
View Article and Find Full Text PDFComput Stat
September 2024
Department of Statistics, Purdue University, West Lafayette, IN 47907.
State estimation for large-scale non-Gaussian dynamic systems remains an unresolved issue, given nonscalability of the existing particle filter algorithms. To address this issue, this paper extends the Langevinized ensemble Kalman filter (LEnKF) algorithm to non-Gaussian dynamic systems by introducing a latent Gaussian measurement variable to the dynamic system. The extended LEnKF algorithm can converge to the right filtering distribution as the number of stages become large, while inheriting the scalability of the LEnKF algorithm with respect to the sample size and state dimension.
View Article and Find Full Text PDFInt J Nanomedicine
January 2025
Department of Drug Sciences, University of Pavia, Pavia, 27100, Italy.
Purpose: The main purpose of the study was the formulation development of nanogels (NHs) composed of chondroitin sulfate (CS) and low molecular weight chitosan (lCH), loaded with a naringenin-β-cyclodextrin complex (NAR/β-CD), as a potential treatment for early-stage diabetic retinopathy.
Methods: Different formulations of NHs were prepared by varying polymer concentration, lCH ratio, and pH and, then, characterized for particle size, zeta potential, particle concentration (particles/mL) and morphology. Cytotoxicity and internalization were assessed in vitro using Human Umbilical Vein Endothelial Cells (HUVEC).
Anal Chem
January 2025
MOE Key Laboratory of Geriatric Nutrition and Health, Department of Bioengineering, Beijing Technology and Business University, Beijing 100048, China.
Multiplexed microRNA (miRNA) detection has proven valuable in disease diagnosis; yet, the development of advanced tools for their analysis remains a subject of broad interest. Here, we propose a novel single-particle method for multiplexed miRNA detection using self-directed hydrogel microspheres, which feature supersegmented compartments for loading analyte probes and an air-encapsulated region that grants the microsphere a unique preferred posture in aqueous solutions. By exploiting microfluidic technology, we can widely adjust the size of the microspheres and the number of compartments can be widely adjusted.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!