{"title":"Can a ramped high-temperature carbon analyser with thermal oxidation be used to quantify soil organic carbon pools?","authors":"Manoharan Veeragathipillai, Leslie Janik, Jeffrey Baldock","doi":"10.1016/j.talanta.2025.128358","DOIUrl":"10.1016/j.talanta.2025.128358","url":null,"abstract":"<p><p>Soil organic carbon (SOC) pools range from easily decomposable particulate, slowly decomposable humic, and resistant organic carbon. These carbon pools, sometimes referred to as POC, HOC and ROC, respectively, can be used as inputs into carbon accounting applications such as the Roth-C model. This study examines whether ramped thermal oxidation, combined with evolved gas (CO<sub>2</sub>) analysis (RTO-EGA) of soil samples at temperature intervals between 110 °C and 1000 °C, can quantify the allocation of SOC to these pools. RTO-EGA ramping profiles of 176 samples were combined with respective soil carbon pool data obtained from physical fractionation and <sup>13</sup>C NMR analysis, into multiple linear regression (MLR) and partial least squares regression (PLSR) models. The samples were split into calibration (110) and validation (51) sets for modelling, and 15 samples omitted due to excessively low decomposition temperatures and associated high model leverage. The samples were also modelled by PLSR using mid-infrared diffuse reflectance (DRIFT) for comparison with RTO-EGA. RTO-EGA and DRIFT calibration and validation accuracies were generally high for POC and HOC, with R<sup>2</sup> values of 0.80-0.95 and RMSE values of 0.10-0.20 %C. Estimates of the ROC pool were relatively less accurate for samples not adequately covered by the calibration set. Since high-temperature carbon analysers are routinely used in most soil testing laboratories, the RTO-EGA approach can be easily adopted for carbon pool analysis. This proof-of-concept study demonstrated that the RTO-EGA method, combined with chemometric modelling, as a rapid and cost-effective method to quantify carbon pools.</p>","PeriodicalId":435,"journal":{"name":"Talanta","volume":"295 ","pages":"128358"},"PeriodicalIF":6.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144191342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Smartphone-enabled detection of urea in animal feed based on a disposable electrode modified with silver nanoparticles decorated on nitrogen-doped graphene nanoplatelets.","authors":"Kiattisak Promsuwan, Chanakarn Sanguarnsak, Ananya Kongsuwan, Jenjira Saichanapan, Asamee Soleh, Kasrin Saisahas, Kritsada Samoson, Sangay Wangchuk, Warakorn Limbut","doi":"10.1016/j.talanta.2025.128431","DOIUrl":"10.1016/j.talanta.2025.128431","url":null,"abstract":"<p><p>A flow injection amperometric sensing method was developed for the detection of urea in animal feed. A screen-printed electrode was modified with a nanocatalyst comprising silver nanoparticles anchored on nitrogen-doped graphene nanoplatelets. The nanocatalyst was synthesized via a two-step hydrothermal procedure and used to modify an electrode as a non-enzymatic electrochemical urea sensing platform. The morphology and structure of the as-synthesized nanocatalyst were investigated, and its electrochemical properties were characterized through electrochemical impedance spectroscopy, cyclic voltammetry, chronocuolometry, and chronoamperometry. The nanocatalyst exhibited good charge transfer ability and electrocatalytic activity for urea oxidation. The sensor fabrication and flow injection amperometric parameters were optimized. Under optimal conditions, the anodic current exhibited a linear correlation with urea concentration from 0.01 to 40 mM (0.6 to 2400 mg L<sup>-1</sup>) with a detection limit of 0.0036 mM (0.22 mg L<sup>-1</sup>). The developed system was highly sensitive (4.0 ± 0.3 μA mM<sup>-1</sup> cm<sup>-2</sup>), showed good repeatability (RSD of 1.4%, n = 10), reproducibility (RSD of 2.5%, n = 10), and operational stability (RSD of 1.01%, n = 100), with a throughput of 60 samples per hour. Furthermore, the proposed system showed resilience against potential interferences commonly found in animal feeds. A strong correlation coefficient between results obtained from the flow injection amperometric sensor and a standard spectrophotometric method underscored the accuracy of the proposed system, ensuring its suitability for urea detection in animal feedstuffs.</p>","PeriodicalId":435,"journal":{"name":"Talanta","volume":"295 ","pages":"128431"},"PeriodicalIF":6.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144281927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TalantaPub Date : 2025-12-01Epub Date: 2025-06-11DOI: 10.1016/j.talanta.2025.128456
Wei Xiao, Fengjuan Xu, Cong Lin, Qian Zhao, Yuanyuan Han, Kunjie Lu, Yanqiong Su, Shibo Shang, Jiting Deng, Ke Gong, Xiaolin Fang, Liangshan Hu, Donglin Cao
{"title":"A simple and low-cost paper chip-based smartphone sensor for enumeration of T lymphocyte subsets.","authors":"Wei Xiao, Fengjuan Xu, Cong Lin, Qian Zhao, Yuanyuan Han, Kunjie Lu, Yanqiong Su, Shibo Shang, Jiting Deng, Ke Gong, Xiaolin Fang, Liangshan Hu, Donglin Cao","doi":"10.1016/j.talanta.2025.128456","DOIUrl":"10.1016/j.talanta.2025.128456","url":null,"abstract":"<p><p>Lymphocyte count reflects the cellular immune function status of the body, and T lymphocyte subsets are of great value in the adjuvant diagnosis, efficacy monitoring, and prognostic assessment of clinical diseases. There is an urgent need to develop a simple and economical cell-counting platform for T lymphocyte subsets to meet clinical needs of cancer prognosis. Based on the vertical flow assay (VFA) and a polystyrene (PS) microsphere-labeled antibody specifically binding to target cells, we established a simple T lymphocyte counting assay (PS-VFA). Labeled cells induced a signal, which was detected on the filter membrane. We used 3D printing to create a cell phone holder and a test kits. The cell phone holder eliminates ambient light interference and provides the appropriate focus, and a smartphone was used for image acquisition and data analysis, revealing the number of T lymphocytes to be tested via RGB signal analysis. The entire detection process takes about 15 min, and the detection device is extremely cheap, about $20, and can be reused. CD3, CD4, and CD8 cells count exhibited a quasilinear response to logarithmic cell concentrations in a single nucleated cell solution, and detection limits ranging from 100 to 1400 cells/μL for CD3(R<sup>2</sup> = 0.96), 100 to 1400 cells/μL for CD4(R<sup>2</sup> = 0.97), and 25 to 800 cells/μL for CD8(R<sup>2</sup> = 0.96), respectively. And the CV values of this method are all less than 10 %. To validate the clinical applicability of this method,16 patients with cancer and 34 healthy individuals samples were measured, the detection results showed a high correlation with the flow cytometry (FCM) analysis. These results revealed that PS-VFA showed good performance compared with flow cytometry and precision evaluation. This analysis approach is a promising alternative for the costly standard flow cytometry-based tools for T lymphocyte subsets in tumor patients in resource-limited settings.</p>","PeriodicalId":435,"journal":{"name":"Talanta","volume":"295 ","pages":"128456"},"PeriodicalIF":6.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144289365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Carbohydrate PolymersPub Date : 2025-11-01Epub Date: 2025-07-29DOI: 10.1016/j.carbpol.2025.123953
Sanjay Ch, Sri Ganga Padaga, Balaram Ghosh, Sanhita Roy, Swati Biswas
{"title":"Corrigendum to \"Chitosan-poly(lactide-CO-glycolide)/poloxamer mixed micelles as a mucoadhesive thermo-responsive moxifloxacin eye drop to improve treatment efficacy in bacterial keratitis\" [Carbohydrate Polymers 312 (2023) 120822].","authors":"Sanjay Ch, Sri Ganga Padaga, Balaram Ghosh, Sanhita Roy, Swati Biswas","doi":"10.1016/j.carbpol.2025.123953","DOIUrl":"https://doi.org/10.1016/j.carbpol.2025.123953","url":null,"abstract":"","PeriodicalId":261,"journal":{"name":"Carbohydrate Polymers","volume":"367 ","pages":"123953"},"PeriodicalIF":12.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144858732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TalantaPub Date : 2025-11-01Epub Date: 2025-05-16DOI: 10.1016/j.talanta.2025.128204
Laura García-Cansino, Karina Boltes, María Luisa Marina, María Ángeles García
{"title":"Erratum to 'Simultaneous enantiomeric separation of linagliptin and clopidogrel by capillary electrophoresis for the individual, combined, and enantiomeric ecotoxicity evaluation on Pseudokirchneriella subcapitata' [Talanta (September 2025) 127992].","authors":"Laura García-Cansino, Karina Boltes, María Luisa Marina, María Ángeles García","doi":"10.1016/j.talanta.2025.128204","DOIUrl":"10.1016/j.talanta.2025.128204","url":null,"abstract":"","PeriodicalId":435,"journal":{"name":"Talanta","volume":" ","pages":"128204"},"PeriodicalIF":5.6,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144085598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}