{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:02:27Z","timestamp":1785402147940,"version":"3.56.0"},"reference-count":37,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,5,26]],"date-time":"2026-05-26T00:00:00Z","timestamp":1779753600000},"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":["12432014"],"award-info":[{"award-number":["12432014"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["12432014"],"award-info":[{"award-number":["12432014"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002855","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2025YFE0107500"],"award-info":[{"award-number":["2025YFE0107500"]}],"id":[{"id":"10.13039\/501100002855","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Shaanxi Province Natural Science Basic Research Program Projects, China","award":["2025JC-YBMS-028"],"award-info":[{"award-number":["2025JC-YBMS-028"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>We herein designed a 64-chamber laminar-flow microfluidic chip with independently addressable culture units capable of establishing spatially heterogeneous chemical environments to mimic tissue microenvironments. Stable chemical gradients were successfully generated within the chip through controlled laminar flow, allowing precise spatial modulation of cellular exposure. Using TNF-\u03b1 as a model stimulus, we observed a clear time delay in NF-\u03baB activation between cells directly exposed to the cytokine and those located on the medium-only side, confirming the establishment of spatially distinct chemical conditions. Notably, even cells not directly exposed to TNF-\u03b1 eventually responded, indicating that molecular diffusion along the static solid\u2013liquid interface serves as an effective delivery route for bioactive molecules. To further demonstrate the platform\u2019s utility, we constructed a skin-mimetic co-culture model of HaCaT keratinocytes and human skin fibroblasts (HSFs) to assess the diffusion and cytotoxic effects of 5-fluorouracil (5-FU). The results revealed that fibroblasts provided protective effects against 5-FU-induced cytotoxicity, likely via paracrine signaling or direct cell\u2013cell interactions. These findings highlight the platform\u2019s capacity for probing not only spatial drug-delivery dynamics but also intercellular interactions under physiologically relevant conditions. This system offers a powerful and versatile tool for studying spatiotemporal signaling, drug screening, and topical therapeutic development.<\/jats:p>","DOI":"10.3390\/mi17060655","type":"journal-article","created":{"date-parts":[[2026,5,26]],"date-time":"2026-05-26T08:16:08Z","timestamp":1779783368000},"page":"655","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Laminar Microfluidic Platform for Probing the Effects of Spatially Heterogeneous Drug Distributions"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4609-4420","authenticated-orcid":false,"given":"Yang","family":"Zeng","sequence":"first","affiliation":[{"name":"State Key Laboratory of Photon-Technology in Western China Energy, Shaanxi Provincial Key Laboratory of Optoelectronic Technology, Institute of Photonics and Photon-Technology, Northwest University, No. 1, Xuefu Avenue, Xi\u2019an 710127, China"},{"name":"School of Physics, Northwest University, No. 1, Xuefu Avenue, Xi\u2019an 710127, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenyan","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Photon-Technology in Western China Energy, Shaanxi Provincial Key Laboratory of Optoelectronic Technology, Institute of Photonics and Photon-Technology, Northwest University, No. 1, Xuefu Avenue, Xi\u2019an 710127, China"},{"name":"School of Physics, Northwest University, No. 1, Xuefu Avenue, Xi\u2019an 710127, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiahao","family":"Fu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Photon-Technology in Western China Energy, Shaanxi Provincial Key Laboratory of Optoelectronic Technology, Institute of Photonics and Photon-Technology, Northwest University, No. 1, Xuefu Avenue, Xi\u2019an 710127, China"},{"name":"Huaxin Micro-Fish (Suzhou) Biotechnology Co., Ltd., No. 99-4-301-01, Fuda Road, Taicang 215411, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bingchen","family":"Che","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Photon-Technology in Western China Energy, Shaanxi Provincial Key Laboratory of Optoelectronic Technology, Institute of Photonics and Photon-Technology, Northwest University, No. 1, Xuefu Avenue, Xi\u2019an 710127, China"},{"name":"School of Physics, Northwest University, No. 1, Xuefu Avenue, Xi\u2019an 710127, China"},{"name":"Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yonggang","family":"Liu","sequence":"additional","affiliation":[{"name":"Laboratory of Stem Cell and Tissue Engineering, Chongqing Medical University, Chongqing 400016, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8985-4824","authenticated-orcid":false,"given":"Xiaobo","family":"Gong","sequence":"additional","affiliation":[{"name":"School of Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9973-608X","authenticated-orcid":false,"given":"Dan","family":"Sun","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Photon-Technology in Western China Energy, Shaanxi Provincial Key Laboratory of Optoelectronic Technology, Institute of Photonics and Photon-Technology, Northwest University, No. 1, Xuefu Avenue, Xi\u2019an 710127, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ce","family":"Zhang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Photon-Technology in Western China Energy, Shaanxi Provincial Key Laboratory of Optoelectronic Technology, Institute of Photonics and Photon-Technology, Northwest University, No. 1, Xuefu Avenue, Xi\u2019an 710127, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4737","DOI":"10.1038\/s41388-021-01918-y","article-title":"B cell heterogeneity, plasticity, and functional diversity in cancer microenvironments","volume":"40","author":"Wei","year":"2021","journal-title":"Oncogene"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Gilson, P., Merlin, J.L., and Harl\u00e9, A. 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