{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,8]],"date-time":"2026-08-08T04:43:38Z","timestamp":1786164218071,"version":"build-2736575974"},"reference-count":43,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T00:00:00Z","timestamp":1785974400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22204095"],"award-info":[{"award-number":["22204095"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["22204095"],"award-info":[{"award-number":["22204095"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100021171","name":"Guangdong Basic and Applied Basic Research Foundation","doi-asserted-by":"crossref","award":["2025A1515011553"],"award-info":[{"award-number":["2025A1515011553"]}],"id":[{"id":"10.13039\/501100021171","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100021171","name":"Guangdong Basic and Applied Basic Research Foundation","doi-asserted-by":"crossref","award":["2023A1515140131"],"award-info":[{"award-number":["2023A1515140131"]}],"id":[{"id":"10.13039\/501100021171","id-type":"DOI","asserted-by":"crossref"}]},{"name":"SUMC Scientific Research Initiation Grant","award":["510858045"],"award-info":[{"award-number":["510858045"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Real-time pH measurement and regulation of microliter-scale liquid samples are critical for microfluidic biochemical applications. However, traditional magnetic stirring for macroscopic systems is not applicable under such microscale conditions. This work develops an ultrasound-assisted screen-printed electrode (SPE) pH sensor integrated with a 3D-printed ultrasonic reflection cell and piezoelectric excitation unit. Ultrasound-induced acoustic streaming accelerates mass transfer inside microliter-scale samples. Upon acid addition, the ultrasonic-assisted system reaches potentiometric equilibrium far more rapidly than the static non-ultrasonic control. Optimized parameters are 30 s ultrasonic duration and 5 Vpp input amplitude. The sensor shows linearity from pH 3.04 to 4.15 with R2 = 0.9919. Phenolphthalein visualization directly confirms ultrasound-enhanced molecular diffusion. Its mass transfer efficiency matches traditional magnetic stirring, and stable fast equilibrium is realized in complex cell culture medium. This acoustofluidic micromixing strategy offers a simple integrated route for pH monitoring and the regulation of micro-volume biological samples.<\/jats:p>","DOI":"10.3390\/bios16080424","type":"journal-article","created":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T08:08:02Z","timestamp":1786003682000},"page":"424","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Enabling Rapid pH Equilibration Through Acoustic Microstreaming for Efficient pH Regulation in Microliter-Scale Samples with Screen-Printed Electrodes"],"prefix":"10.3390","volume":"16","author":[{"given":"Ziyi","family":"Xiao","sequence":"first","affiliation":[{"name":"Bio-Analytical Laboratory, Shantou University Medical College, Shantou 515041, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruyi","family":"Deng","sequence":"additional","affiliation":[{"name":"Bio-Analytical Laboratory, Shantou University Medical College, Shantou 515041, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xin","family":"Liu","sequence":"additional","affiliation":[{"name":"Bio-Analytical Laboratory, Shantou University Medical College, Shantou 515041, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiahuan","family":"Zheng","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Shantou University Medical College, Shantou 515041, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3978-0908","authenticated-orcid":false,"given":"Kaisong","family":"Yuan","sequence":"additional","affiliation":[{"name":"Bio-Analytical Laboratory, Shantou University Medical College, Shantou 515041, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e202300369","DOI":"10.1002\/tcr.202300369","article-title":"Advances in pH Sensing: From Traditional Approaches to Next-Generation Sensors in Biological Contexts","volume":"24","author":"Abbas","year":"2024","journal-title":"Chem. 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