{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T13:07:03Z","timestamp":1789564023878,"version":"build-2803163510"},"reference-count":29,"publisher":"Public Library of Science (PLoS)","issue":"10","license":[{"start":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T00:00:00Z","timestamp":1760054400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Objectives<\/jats:title>\n<jats:p>To evaluate the stability, accuracy, and clinical performance of the Snibe CO\u2082 assay compared with the Roche CO\u2082 reagent and to investigate factors affecting total CO\u2082 measurements in different clinical conditions.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods<\/jats:title>\n<jats:p>Total CO\u2082 was measured in patient samples using enzymatic assays. Stability was assessed over time, and CO\u2082 loss was examined in different blood collection tubes. Method comparison was conducted between the Snibe and the Roche CO\u2082 assays in various diseases.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>The Snibe CO\u2082 assay showed excellent linearity (r\u2009=\u20090.9997) and maintained stability for 42 days without recalibration, with control material deviations within \u00b15% of the target. CO\u2082 loss was observed in uncapped non-anticoagulant tubes (24.0% decline over 48 hours), but was less in EP tubes (9.4% decline). Significant differences of median CO\u2082 measurements were observed in only the renal group (Snibe: 13.35 mmol\/L, Roche: 12.80 mmol\/L) and the cardiovascular disease group (Snibe: 25.90 mmol\/L, Roche: 26.40 mmol\/L) versus the healthy group (Snibe: 22.70 mmol\/L, Roche: 22.90 mmol\/L) for both the Snibe and Roche assays.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>The Snibe CO\u2082 assay demonstrated superior stability and comparable accuracy compared with the Roche reagent. Preanalytical CO\u2082 loss remains a critical issue, emphasizing the need for standardized sample handling. Given the correlation between total CO\u2082 and bicarbonate levels, accurate measurement is critical for diagnosing metabolic disorders. Laboratories should establish protocols to minimize errors and ensure reliable acid-base assessment in clinical practice.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0334228","type":"journal-article","created":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T17:26:01Z","timestamp":1760117161000},"page":"e0334228","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":1,"title":["Stability, accuracy, and clinical performance of enzymatic total CO\u2082 measurement: Evaluation of the Snibe and Roche 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