Aqueous Samples Research Articles

Developing smart phone-based image scanning densitometric method for on-site analysis of Cr(VI), Ni(II), and Fe(II) in aqueous medium for monitoring environmental and biological samples.

The main objective of this work is to introduce "image scanning densitometry" for the elimination of drawbacks of the spectrometric methods, which are conventionally used for analysis of metal ions in aqueous samples. This method is beneficial because a small amount of analyte was used for toxicological chemical analysis in medical diagnostics and environmental monitoring along with its portable nature for on-spot analysis by integrating AI technology with conventional methods. By using this method, colorimetric reactions are performed on TLC plates and results are quantified by digitizing the area of spots by using image scanning devices and specially developed software. The analyte concentration is proportional to the RGB (red, green, blue) color densities of the quantified spots. The raw color densities of the spots were transformed by using Kubelka-Munk transformation in results, which give information about the different dynamic ranges. Different metals, such as nickel (II), chromium (VI), and iron (II), were quantified by using their aqueous samples for monitoring toxic contaminants of water streams. The detection limits are 3.8, 3.94, and 6.78 ppm for Cr(VI), Ni(II), and Fe(II) correspondingly.

Bifunctional performance of robust filter material based on biomimetically synthesized CeO2/ZnO and nanolignin supported on microcrystalline cellulose for water reclamation.

Bifunctional performance of robust filter material based on biomimetically synthesized CeO2/ZnO and nanolignin supported on microcrystalline cellulose for water reclamation.

Development of 1,3-Oxazinoquinolin-4-one-based Derivatization Reagents for the Discrimination of Amine Analytes via High-Resolution Mass Spectrometry.

We designed and synthesized novel precolumn derivatization reagents exhibiting a 1,3-oxazinoquinoline-4-one (Oq) structure to enable differentiation of amine types using quadrupole orbitrap high-resolution mass spectrometry (MS/MS). The developed Oq reagents successfully derivatized amine compounds in aqueous samples under mild basic conditions. Particularly, Oq1─a reagent featuring nitrophenyl-activated ester tethered with glycine linkage─clearly distinguished primary amines, secondary amines, and amines bearing other basic moieties, based on the generation of characteristic positive fragment ions at m/z 190 and m/z [M + H - 171]. We therefore propose the use of the logarithmic value of the fragment ion ratio (logFIR) between m/z 190 and m/z M + H - 171] after derivatization with Oq1 as a quantitative index. Among the 28 tested amino compounds, the estimated ranges of logFIR were 0.03 to 1.6 for primary amines, -0.02 to -1.3 for secondary amines, and -1.2 to -2.4 for amines bearing other basic moieties. Therefore, Oq1 enables differentiation of amine classes based on the fragmentation patterns and corresponding logFIR values. To demonstrate its applicability, Oq1 was employed for the nontarget analysis of components in natural orange juice. The results showed that the logFIR values enhanced the accuracy of component identification. This derivatization strategy offers a powerful tool for amino group analysis via liquid chromatography-MS/MS, potentially advancing qualitative multicomponent profiling in complex matrices.

A green and engineered magnetic ionic liquid system for selective extraction and trace determination of thorium in industrial and environmental samples.

Thorium contamination poses serious health and environmental risks, highlighting the need reliable detection methods. This study presents a green and engineered analytical system for the selective extraction and determination of thorium ions in ores and aqueous samples. A task-specific hydrazinium-based ionic liquid, 2-(4-hydroxybenzyl)hydrazinium chloride ([Hyim][Cl]), was synthesized and characterized using 1HNMR, 13CNMR, FTIR, VSM, and CHNO analysis. The ionic liquid demonstrated strong affinity toward thorium ions and enabled efficient magnetic separation. Experimental parameters were optimized via a design of experiments (DOE) approach. Under optimal conditions, the system achieved 98.6% extraction efficiency, a detection limit of 0.11µg/L, a quantification limit of 0.22µg/L, a linear dynamic range of 5.0-200.0µg/L, intra-day relative standard deviation of 2.17%, inter-day of 2.86%, preconcentration factors of 122, enrichment factor of 100 and recovery rates between 96.4 and100.5% in real water and wastewater samples.

Enhanced microextraction kinetics: Sorptive-dispersive vs. conventional techniques on rotating disks.

Enhanced microextraction kinetics: Sorptive-dispersive vs. conventional techniques on rotating disks.

Biogenic synthesis of silver nanoparticles for colorimetric detection of Fe3+ in environmental samples: DFT calculations and molecular docking studies.

Biogenic synthesis of silver nanoparticles for colorimetric detection of Fe3+ in environmental samples: DFT calculations and molecular docking studies.

Real-world clinical insights and aqueous humor biomarker analysis of diabetic macular edema subtypes classified by OCT following intravitreal injections

PurposeThis study aimed to observe the morphological changes and visual outcomes in diabetic macular edema (DME) subtypes based on optical coherence tomography classification following intravitreal injection.MethodsNinety-four eyes from seventy-eight patients were enrolled between July 1, 2018, and June 30, 2023. Best-corrected visual acuity (BCVA), central subfield thickness, and morphological changes were examined at each follow-up visit. Aqueous humor samples were obtained before intravitreal injection of anti-vascular endothelial growth factor or cataract surgery. The inflammatory cytokine profile in the aqueous humor of each DME subtype was analyzed to explore potential contributions.ResultsThe BCVA in the diffuse retinal thickening group was significantly improved at the last follow-up (p = 0.006), but no significant change in central subfield thickness was observed. Conversely, the BCVA in the cystoid macular edema and serous retinal detachment groups did not significantly improve, although a significant reduction in central subfield thickness was observed in both groups at the final follow-up (both p < 0.05). Principal component analysis of proteomic data revealed clear segregation between samples from patients with different DME subtypes and those from the control group. 59 proteins were found to be significantly regulated in the diffuse retinal thickening group compared to those in the control group. Of these, 10 proteins were upregulated, whereas 49 were downregulated. In the cystoid macular edema group, 30 proteins were significantly regulated, with 8 proteins upregulated and 22 downregulated. In the serous retinal detachment group, 87 proteins showed significant changes: 24 exhibited increased expression and 63 decreased expression.ConclusionsThe diffuse retinal thickening subtype showed a better response and cystoid macular edema was the most common morphological subtype of DME after intravitreal injection treatment in real-world clinical observations. The variations in protein expression of aqueous humor suggested distinct pathological mechanisms for each DME subtype, laying the groundwork for more targeted treatment strategies.

Oleic acid association with primary angle-closure glaucoma: A finding using metabolomics.

Oleic acid association with primary angle-closure glaucoma: A finding using metabolomics.

Cyclocryotherapy applied at the 3 o'clock and 9 o'clock positions combined with anti-VEGF injections for advanced neovascular glaucoma.

This study aimed to investigate the efficacy of cyclocryotherapy applied at the 3 o'clock and 9 o'clock positions in combination with intravitreal anti-vascular endothelial growth factor (VEGF) injections in patients with advanced neovascular glaucoma (NVG). Medical records of patients diagnosed with NVG who underwent cyclocryotherapy at the 3 o'clock and 9 o'clock positions combined with intravitreal anti-VEGF injections between January 2021 and January 2023 were retrospectively reviewed. Baseline and follow-up data including intraocular pressure (IOP), best-corrected visual acuity, perioperative pain scores using numeric rating scale, intraocular cytokines levels, and surgical complications, were analyzed. A successful surgical outcome was defined as an IOP below 21mmHg with at least a 30% reduction from baseline. A total of 20 eyes from 20 patients were included. Elevated levels of several inflammatory mediators and angiogenic cytokines were detected in aqueous and vitreous samples. Pain scores significantly decreased scores at one month postoperatively (0.5±0.9) compared to preoperative values (6.2±3.0) (P<0.001). At the 3-month follow up, the mean IOP was 26.4±15.9mmHg, representing a 39.0% reduction from baseline (43.2±10.6mmHg) (P=0.003). At the final follow-up visit (mean duration 13.3±4.5months), the mean IOP was 26.6±15.2mmHg, corresponding to a 38.4% reduction from baseline. No cases of anterior segment ischemia or phthisis bulbi were documented during the follow-up period. The surgical success rate was 55% at 3months and 60% at the final follow-up. Cyclocryotherapy applied at the 3 o'clock and 9 o'clock position combined with anti-VEGF treatment presents a potential treatment alternative for advanced NVG. Further research is needed to validate its long-term efficacy and safety profile.

Uranium immobilization via sulfur-modified Fe0 nanoparticles: U(VI) trapping kinetics and long-term stability evaluation.

Uranium immobilization via sulfur-modified Fe0 nanoparticles: U(VI) trapping kinetics and long-term stability evaluation.

Detection of Nickel Ions in Industrial Water by Fabricating Carbon Paste Electrode modified with Nanoparticles

Nickel must be carefully monitored due to its severe health and environmental impacts. Many innovative nickel ion detection (Ni+2) methods have been developed. These methods vary from fluorescent and nanoscale sensors to biosensors, optical electronics, and larger devices. In this research, a new detector electrode sensor was developed to detect and estimate nickel in industrial and well-water. Nickel oxide II (NiO) nanoparticles were synthesized using an extract of Capparis Spinosa leaves, washed, and dried. Then, the material from fresh green leaves has been extracted. The synthesized NiONPs were incorporated into a carbon paste matrix, forming a modified electrode for the selective detection of Ni+2 ions in aqueous samples. NiONPs and their external characteristics have been studied by various techniques. The particle size measured was approximately (15.57) nm. Scanning Electron Microscope SEM analysis revealed that the nanoparticles exhibited both spherical and irregular shapes. In the UV-VIS spectrometry, the peak was at the wavelength (366) nm; this confirms that nickel particles have been obtained. The electrode demonstrated selectivity and good sensitivity with linear response (10-1 - 10-9), correlation coefficient (0.9987), electrode lifespan (130) days, and the ideal temperatures for the electrode were measured and determined (15-40) °C. The best degree of acidity (pH) to work (5-8), with a slope value at (25) °C, was (28.5) mV/decade. Limit of detection 8.335x10-9 mol/L. The recovery percentage is 100.8%. This work successfully estimated nickel ions in wells and industrial waters.

Ceruloplasmin and Ferritin Changes in Ocular Fluids from Patients with Vitreoretinal Diseases: Relation with Neuroinflammation and Drusen Formation.

This pilot study explored whether the ceruloplasmin (CP) and ferritin (FT) levels in ocular fluids could serve as biomarkers for early neurodegenerative diseases (Alzheimer's, Parkinson's, and other dementias). CP and FT are known to modulate neurodegenerative tissue responses. We analysed aqueous and vitreous samples from 26 patients (8M/18F, aged 60-85) who were undergoing elective vitreoretinal (VR) surgery. Of these, 14 had idiopathic epiretinal membranes (ERMs), 6 had idiopathic macular holes (MH), and 6 were patients with Alzheimer's disease (AD) who presented with VR disorders (VRDs). CP, FT, and selected neuroinflammatory mediators such as interferon γ (IFN-γ), interleukin (IL-6), vascular endothelial growth factor (VEGF), nerve growth factor (NGF), and brain-derived neurotrophic factor (BDNF) were quantified. Odds ratio analysis was applied to assess the CP/FT ratio's association with subretinal drusen. We found distinct CP and FT profiles in VRD samples. In aqueous fluid, the CP increased and the FT decreased in early-stage ERM, which reduced the CP/FT ratio. Similar patterns were observed in vitreous fluid. The CP levels correlated with the VEGF (aqueous), IL-4 (vitreous), NGF, and BDNF levels; FT correlated with IL-6 and NGF. A higher CP/FT ratio was associated with increased risk for neurodegenerative conditions. Our findings support the quantification of CP and FT in ocular fluids as a promising approach for identifying early neurodegenerative changes and suggest that the CP/FT ratio may be linked to drusen imaging and clinical neurodegenerative history.

Evaluation of sevoflurane interference with forensic blood ethanol analysis, including sevoflurane stability, and an authentic case

Abstract Sevoflurane, a volatile anesthetic routinely used in clinical settings, was investigated to determine the extent of its interference with in-house forensic blood ethanol analysis. This potential interference could have a significant impact on the analysis and subsequently the interpretation of ethanol in human performance antemortem forensic toxicology casework (e.g. Driving While Under the Influence (DWI) cases). Aqueous samples with ethanol concentrations spanning 0.02–0.40 g/100 mL were fortified with sevoflurane and analyzed using two different dual-column headspace-­gas chromatography with flame ionization detection instruments. Sevoflurane was found to elute as an interference peak near ethanol on column 1 (BAC1) and co-elute with ethanol on column 2 (BAC2); the differences were due to the column chemistries. Analyte identification and quantification acceptance criteria monitored included peak-to-valley ratio (resolution) and percent difference between individual column concentrations and the average value of both column concentrations. A 2023 DWI case exhibited potential sevoflurane interference and demonstrated the importance of ethanol reporting acceptance criteria for detecting such interference. In the majority of experiments with sevoflurane and ethanol present in the samples, sevoflurane presence caused failing acceptance criteria to report ethanol results, but if acceptance criteria were met, the ethanol concentration was slightly elevated. An additional sevoflurane stability study showed that the highly volatile sevoflurane could evaporate between analysis and re-analysis of blood samples due to additional tube openings. The decrease of sevoflurane was monitored at each opening of the tube using relative peak areas. HFSC re-analyzes suspected sevoflurane samples, as the additional tube openings could allow sevoflurane to evaporate.

Determination of mitoxantrone in environmental waters: a spectrophotometric method with preconcentration by salt saturated pipette-tip micro solid phase extraction using molecularly imprinted polymer

In this research, a fast and simple spectrophotometric method is presented for mitoxantrone determination in various aqueous samples. It utilizes preconcentration by salt saturated pipette-tip micro solid phase extraction with a selective molecularly imprinted polymer adsorbent packed in a micropipette tip. Prior to sample loading, they were saturated with a mixture of NaCl, Mg (NO3)2.6H2O and KNO3 salts, enhancing extraction efficiency by 27.5% compared to salt-free conditions. Key microextraction parameters (amount of molecularly imprinted polymer, sample pH, eluent type/volume, and adsorption/desorption cycles) were optimized using response surface methodology and one-variable-at-a-time methods. The method achieves a low detection limit (0.2 μg L−1) and a wide linear range (1–1000 μg L−1). An enrichment factor of 49 is obtained with excellent accuracy (relative standard deviation <4.4%). The method was validated by comparing it to a standard high performance liquid chromatography protocol, as well as spiking real samples in three concentration levels. The method successfully detected low levels of mitoxantrone in various water samples.

Aqueous Humor Cytokine Levels as Prognostic Factors for Ultrasound Cycloplasty Outcomes in Primary Glaucoma Patients.

To evaluate the levels of 40 cytokines in the aqueous humor (AH) and their correlation with ultrasound cycloplasty (UCP) outcomes in patients with primary glaucoma. Aqueous humor samples were collected from 38 primary glaucoma patients after UCP procedure. The cytokines were measured via antibody arrays and evaluated via Cox proportional hazards regression to determine the UCP outcomes. Follow-up visits were performed at 1 day, 1 week, and 1 and 3 months postoperatively. The study subjects were allocated into success and failure groups based on surgical results. Significantly high MCP-1 (P=0.034) and TGF-β1 levels (P=0.041) were observed in the failure group. Both univariate and multivariate analyses indicated that high MCP-1 (P=0.040, P=0.018) and TGF-β1 (P=0.049, P=0.041) levels were significant risk factors for UCP failure. The levels of MCP-1 were positively correlated with intraocular pressure (IOP) at 1 day (r=0.416, P=0.010) and 3 months (r=0.329, P=0.044) postoperatively. In primary glaucoma patients, high postoperative levels of MCP-1 and TGF-β1 were significant risk factors for UCP failure. MCP-1 levels in the AH could be a potential indicator for predicting postoperative IOP.

Sensitive Detection of Copper (II) Ions in Aqueous Solutions Using Thioglycolic Acid-Capped Ce-Doped ZnS Nanoparticles Based Fluorescent Probe.

The synthesis of fluorescent water dispersible thioglycolic acid (TGA)-capped Ce-doped ZnS nanoparticles (coded as Ce-ZnS@TGA) was carried out using environment friendly co-precipitation approach. The as-synthesized nanoparticles were characterized using powder X-ray diffraction (PXRD), HRTEM, Energy Dispersive X-ray spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy, UV-visible spectroscopy, and fluorescence spectroscopy. The Ce-ZnS@TGA probe was found to show significant enhancement on addition of urea. Further, the fluorescence intensity of the Ce-ZnS@TGA-urea complex was quenched on addition of Cu2+ ions. The Ce-ZnS@TGA-urea complex was used as a fluorescence probe for detection of Cu2+ ions in aqueous samples. The quenching of the fluorescence intensity of Ce-ZnS@TGA-urea was possibly due to non-radiative recombination as Cu2+ions act as electron trapping center. The LODs for detection of urea and Cu2+ ions was determined to be 2.3mM and 26.6 µΜ respectively. The factors affecting the detection of Cu2+ ions such as presence of other metal ions were also investigated and the optimum pH value for the sensor was evaluated. The proposed method was also employed to detect trace Cu2+concentrations in real water samples with satisfactory results.

Elucidating the Impact of Wildfire Molecular Tracers on Nitrous Acid (HONO) Production from Aqueous Nitrate Photochemistry.

Nitrous acid (HONO), a gaseous tropospheric pollutant, significantly influences the oxidative potential of the atmosphere as a major source of hydroxyl radicals (•OH). Recently, HONO has been identified as a primary and secondary product of wildfire smoke, yet mechanisms for its formation are poorly understood. In this study, wildfire-emitted organic compounds, such as levoglucosan (LG), syringic acid (SA), and vanillic acid (VA), were studied to investigate their impact on HONO production from aqueous nitrate photochemistry. The presence of SA and VA increased gas-phase HONO yields by 3- and 5-fold, respectively, while LG increased HONO production the most, 6-fold. Furthermore, a nonlinear relationship between HONO and LG concentration was found. Aqueous nitrate samples exposed to lower concentrations of LG were shown to produce an LG-derived carbonyl compound, whereas the samples exposed to a higher LG concentration resulted in an LG dimer. The mechanisms as to how these differences in products affect HONO enhancement are discussed. Gas-phase HONO yields were quantified using incoherent broadband cavity enhanced absorption spectroscopy (IBCEAS), and identification of any condensed phase products from aqueous nitrate samples was done by high resolution mass spectrometry. Studying nitrate photochemistry in the presence of wildfire-emitted organic compounds can potentially minimize the knowledge gap on the observed high concentrations of gaseous HONO formation during biomass burning events.

Etiology of Iridocorneal Endothelial Syndrome: Viral Infection and Immune Suppression.

Iridocorneal endothelial (ICE) syndrome is a rare ocular disease affecting the anterior segment, leading to cornea edema and glaucoma. Its unclear etiology limits clinical management to symptomatic interventions. This study uses diverse methodologies to explore potential viral sequences in patients' samples and to elucidate the transcriptomic profiles of ICE cells. We used a convenience sampling method, including all eligible patients for analysis. We reviewed polymerase chain reaction (PCR) results for herpes viruses across all samples obtained from ICE syndrome patients at our institution. To further delve into potential pathogenic involvement, we used metagenomic sequencing and whole-genome sequencing techniques on samples. We used smart-seq2 RNA sequencing to explore the transcriptomic features of ICE cells compared with normal cells. In our PCR tests involving 141 samples, only two positive results were detected in the aqueous humor. Furthermore, the application of metagenomic sequencing on three aqueous humor samples and three corneal endothelium samples, along with whole-genome sequencing on one corneal endothelium sample, yielded no evidence of viral sequences. RNA sequencing revealed upregulated cell growth and neuronal death in ICE cells, alongside downregulated expression in extracellular matrix composition, cell adhesion, and immune response functions. Our findings from multiple sequencing assays consistently indicate the absence of compelling evidence supporting viral infection in patients with ICE syndrome. Furthermore, the transcriptional analysis of ICE cells reveals a distinct profile characterized by upregulated cell growth and suppressed immune response. Future studies are necessary to validate these findings and improve the generalizability of the results.

The Effects of Lutein-Containing Supplement Intake on Glycation Inhibition Among Diabetic Patients with Cataracts

Glycation is known as an important factor inducing human diseases, including diabetic complications. As oxidative stress contributes to procedures of glycation, antioxidants may inhibit glycation and delay the progression of diabetic complications. Our previous investigation of human aqueous humor after the intake of a lutein-containing supplement demonstrated increases in antioxidative activities and decreases in peroxidative products. This study enrolled 25 patients with diabetes (DM group) and 100 age-matched controls. Aqueous humor samples were collected during cataract surgery before and after 6 weeks of oral intake of the lutein-containing antioxidant supplement, Ocuvite + Lutein®. The carboxymethyl-lysine level (CML) was measured as an indicator of glycation. Levels of superoxide dismutase activities (SOD) and total hydroperoxide (TH) were measured as indicators of oxidation. Changes after intake and the differences between age-matched controls and the DM group were evaluated. CML decreased after intake among the DM group, while there were no changes among the age-matched controls. SOD was significantly lower and TH was significantly higher in the DM group as compared to the age-matched controls, both before and after intake. In line with the decreases in glycation, the intake of lutein-containing antioxidant supplements may inhibit diabetic complications in diabetic patients.

Removal of pendimethalin from aqueous samples using peanut shell biochar-Fe3O4 magnetic composite; adsorption studies, thermodynamic and kinetics

Removal of pendimethalin from aqueous samples using peanut shell biochar-Fe3O4 magnetic composite; adsorption studies, thermodynamic and kinetics