{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T07:09:57Z","timestamp":1792134597037,"version":"4.4.0"},"reference-count":56,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,5,24]],"date-time":"2025-05-24T00:00:00Z","timestamp":1748044800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Monash University","award":["2020\/2021"],"award-info":[{"award-number":["2020\/2021"]}]},{"name":"Monash University","award":["DP180103484"],"award-info":[{"award-number":["DP180103484"]}]},{"name":"Australian Research Council Discovery Project","award":["2020\/2021"],"award-info":[{"award-number":["2020\/2021"]}]},{"name":"Australian Research Council Discovery Project","award":["DP180103484"],"award-info":[{"award-number":["DP180103484"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Albuminuria is a sensitive biomarker of kidney dysfunction, and the albumin\/creatinine ratio (ACR) is an essential measure for monitoring diabetic kidney disease (DKD). Abnormal levels can indicate a propensity for progressive renal failure and other complications such as cardiovascular diseases. This study employed UV\/Visible spectroscopy to analyze aqueous urine samples spiked with bovine serum albumin (BSA) and creatinine at clinically relevant concentrations (0\u201330 mg\/L for albumin and 600\u20131800 mg\/L for creatinine) using a multivariate method. UV\/Visible spectra of co-spiked samples recorded in triplicate revealed distinct bands at 229 nm and 249 nm, corresponding to BSA and creatinine, respectively, alongside other amino acid bands. Partial Least Squares Regression (PLS-R) analysis for BSA yielded a Root Mean Square Error of Calibration (RMSEC) and Cross-Validation (RMSECV) values of 66.93 and 73.92 mg\/L, respectively. For creatinine, RMSEC and RMSECV values were 244.32 and 275.65 mg\/L, respectively. Prediction models for both BSA and creatinine compared to ELISA demonstrated a robust performance with R2PRED values of 0.96 and 0.95, respectively, indicating strong model reliability. The Limit of Detection (LOD) for co-spiked samples was 19.82 mg\/L for BSA and 58.43 mg\/L for creatinine. The significance of the achieved Limit of Detection (LOD) lies in its ability to measure concentrations well below the normal physiological ranges of 0\u201330 mg\/L for albumin and 600\u20131800 mg\/L for creatinine. These results demonstrate the proof of concept of applying an UV\/Visible-spectroscopy-based method as a rapid, cost-effective point-of-care (PoC) tool for ACR measurements, offering promising applications in the early diagnosis, monitoring, and prognosis of diabetic kidney disease and associated cardiovascular complications. The next stage will involve a pilot trial to evaluate the technology\u2019s potential using clinical patients.<\/jats:p>","DOI":"10.3390\/s25113307","type":"journal-article","created":{"date-parts":[[2025,5,25]],"date-time":"2025-05-25T20:26:50Z","timestamp":1748204810000},"page":"3307","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Rapid, Precise, and Clinically Relevant Quantification of Urinary Albumin and Creatinine Using a NanoDrop UV\/Vis Spectrophotometer"],"prefix":"10.3390","volume":"25","author":[{"given":"Keith E.","family":"Dias","sequence":"first","affiliation":[{"name":"Monash Biospectroscopy Group, School of Chemistry, Monash University, Clayton, VIC 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karly C.","family":"Sourris","sequence":"additional","affiliation":[{"name":"Department of Diabetes, School of Translational Medicine, Monash University, Melbourne, VIC 3004, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2764-2930","authenticated-orcid":false,"given":"Jay C.","family":"Jha","sequence":"additional","affiliation":[{"name":"Department of Diabetes, School of Translational Medicine, Monash University, Melbourne, VIC 3004, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2192-5822","authenticated-orcid":false,"given":"Karin","family":"Jandeleit-Dahm","sequence":"additional","affiliation":[{"name":"Monash Biospectroscopy Group, School of Chemistry, Monash University, Clayton, VIC 3800, Australia"},{"name":"Department of Diabetes, School of Translational Medicine, Monash University, Melbourne, VIC 3004, Australia"},{"name":"German Diabetes Centre, Institute for Clinical Diabetology, Leibniz Centre for Diabetes Research at Heinrich Heine University, 40225 Dusseldorf, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3581-447X","authenticated-orcid":false,"given":"Bayden R.","family":"Wood","sequence":"additional","affiliation":[{"name":"Monash Biospectroscopy Group, School of Chemistry, Monash University, Clayton, VIC 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S194","DOI":"10.2337\/dc08-s249","article-title":"Microalbuminuria in type 2 diabetes and hypertension: A marker, treatment target, or innocent bystander?","volume":"31","author":"Basi","year":"2008","journal-title":"Diabetes Care"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1016\/j.kisu.2017.10.003","article-title":"Diagnosis of diabetic kidney disease: State of the art and future perspective","volume":"8","author":"Persson","year":"2018","journal-title":"Kidney Int. 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