{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T23:18:29Z","timestamp":1788218309921,"version":"build-2803163510"},"reference-count":52,"publisher":"American Chemical Society (ACS)","issue":"33","license":[{"start":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T00:00:00Z","timestamp":1786579200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,25]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>A fluorescence-based sensing platform for protease activity determination was developed using l-arginine-doped carbon dots (CDs), with papain as a model protease. CDs were synthesized via a rapid microwave-assisted method and purified by either dialysis (D-CDs) or syringe filtration (SF-CDs) to investigate the impact of purification-dependent surface chemistry on enzyme\u2013nanoparticle interactions and sensing kinetics. The detection mechanism is based on fluorescence quenching resulting from surface interactions between N\u03b1-benzoyl-l-arginine p-nitroanilide (BAPNA) and the CDs, with fluorescence recovery occurring upon protease-catalyzed substrate hydrolysis. Both CD systems exhibited rapid fluorescence responses upon enzyme addition; however, distinct time-dependent behaviors were observed. SF-CDs achieved a stable fluorescence signal rapidly, whereas D-CDs displayed a nonmonotonic fluorescence response before stabilization, underscoring the importance of surface accessibility and interfacial interactions in modulating enzyme-induced fluorescence. These kinetic differences produced dual linear response regions, allowing reliable quantification of protease activity across a broad concentration range. The method was successfully applied to quantify protease activity in commercial fruit juice samples, reporting results as papain-equivalent protease activity. Recovery values were matrix-dependent, with clarified matrices showing satisfactory accuracy, while polyphenol-rich samples exhibited signal enhancement due to protein\u2013polyphenol interactions. The assay demonstrated good precision, with intra- and interday relative standard deviations (%RSD) below 3.5%. In summary, this study presents a rapid and sensitive CD-based fluorescence platform for protease activity determination while highlighting purification-dependent surface accessibility as a key factor governing interfacial sensing behavior.<\/jats:p>","DOI":"10.1021\/acsomega.6c05574","type":"journal-article","created":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T19:02:29Z","timestamp":1786647749000},"page":"50135-50146","source":"Crossref","is-referenced-by-count":0,"title":["Fluorescence Turn-Off\nSensing of Protease Activity\nwith Carbon Dots: Papain as a Model System for Surface Accessibility-Driven\nInterfacial Kinetics"],"prefix":"10.1021","volume":"11","author":[{"given":"Wannapa","family":"Phunswat","sequence":"first","affiliation":[{"name":"Silpakorn University , , ,","place":["Nakhon Pathom, Thailand, 73000"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1550-1695","authenticated-orcid":true,"given":"Cheewita","family":"Suwanchawalit","sequence":"additional","affiliation":[{"name":"Silpakorn University , , ,","place":["Nakhon Pathom, Thailand, 73000"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0771-8547","authenticated-orcid":true,"given":"Nichanun","family":"Sirasunthorn","sequence":"additional","affiliation":[{"name":"Silpakorn University , , ,","place":["Nakhon Pathom, Thailand, 73000"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,8,13]]},"reference":[{"issue":"3","key":"2026083119113978300_cit1","doi-asserted-by":"publisher","first-page":"223","DOI":"10.1080\/15422119.2019.1677249","article-title":"An overview of proteases: production,\ndownstream processes and industrial applications","volume":"50","author":"Gimenes","year":"2021","journal-title":"Sep. 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