{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T04:04:38Z","timestamp":1784779478158,"version":"3.55.0"},"reference-count":45,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,1,3]],"date-time":"2023-01-03T00:00:00Z","timestamp":1672704000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["21974084"],"award-info":[{"award-number":["21974084"]}]},{"name":"National Natural Science Foundation of China","award":["22274095"],"award-info":[{"award-number":["22274095"]}]},{"name":"National Natural Science Foundation of China","award":["2021TD-42"],"award-info":[{"award-number":["2021TD-42"]}]},{"name":"National Natural Science Foundation of China","award":["GK202206041"],"award-info":[{"award-number":["GK202206041"]}]},{"name":"National Natural Science Foundation of China","award":["GK202207013"],"award-info":[{"award-number":["GK202207013"]}]},{"name":"Innovation Capability Support Program of Shaanxi","award":["21974084"],"award-info":[{"award-number":["21974084"]}]},{"name":"Innovation Capability Support Program of Shaanxi","award":["22274095"],"award-info":[{"award-number":["22274095"]}]},{"name":"Innovation Capability Support Program of Shaanxi","award":["2021TD-42"],"award-info":[{"award-number":["2021TD-42"]}]},{"name":"Innovation Capability Support Program of Shaanxi","award":["GK202206041"],"award-info":[{"award-number":["GK202206041"]}]},{"name":"Innovation Capability Support Program of Shaanxi","award":["GK202207013"],"award-info":[{"award-number":["GK202207013"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["21974084"],"award-info":[{"award-number":["21974084"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["22274095"],"award-info":[{"award-number":["22274095"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["2021TD-42"],"award-info":[{"award-number":["2021TD-42"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["GK202206041"],"award-info":[{"award-number":["GK202206041"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["GK202207013"],"award-info":[{"award-number":["GK202207013"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Stimuli-responsive drug release and photodynamic therapy (PDT) have aroused extensive attention for their enormous potential in antitumor treatment. pH-responsive drug delivery systems (PFE-DOX-1 and PFE-DOX-2) based on water-soluble conjugated polymers were constructed in this work for high-performance synergistic chemo-\/PDT therapy, in which the anticancer drug doxorubicin (DOX) is covalently attached to the side chains of the conjugated polymers via acid-labile imine and acylhydrazone bonds. Concurrently, the intense fluorescence of poly(fluorene-co-ethynylene) (PFE) is effectively quenched due to the energy\/electron transfer (ET) between the PFE-conjugated backbone and DOX. Effective pH-responsive drug release from PFE-DOX-2 is achieved by the cleavage of acylhydrazone linkages in the acidic tumor intracellular microenvironment. Additionally, the drug release process can be monitored by the recovered fluorescence of conjugated polymers. Furthermore, the conjugated polymers can produce reactive oxygen species (ROS) under light irradiation after drug release in an acidic environment, which prevents possible phototoxicity to normal tissues. It is noted that PFE-DOX-2 demonstrates remarkable antitumor cell performance, which is attributed to its efficient cell uptake and powerful synergistic chemo-\/PDT therapeutic effectiveness. This report thus provides a promising strategy for in vivo anticancer treatment with the construction of a stimuli-responsive multifunctional drug delivery system.<\/jats:p>","DOI":"10.3390\/molecules28010399","type":"journal-article","created":{"date-parts":[[2023,1,3]],"date-time":"2023-01-03T02:51:39Z","timestamp":1672714299000},"page":"399","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["A pH-Responsive Drug Delivery System Based on Conjugated Polymer for Effective Synergistic Chemo-\/Photodynamic Therapy"],"prefix":"10.3390","volume":"28","author":[{"given":"Chen","family":"Zhang","sequence":"first","affiliation":[{"name":"Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi\u2019an 710119, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiong","family":"Yuan","sequence":"additional","affiliation":[{"name":"Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi\u2019an 710119, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ziqi","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi\u2019an 710119, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9979-6808","authenticated-orcid":false,"given":"Yanli","family":"Tang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi\u2019an 710119, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3297","DOI":"10.1021\/acs.chemrev.0c00383","article-title":"Challenges and Opportunities in Cancer Drug Resistance","volume":"121","author":"Ward","year":"2021","journal-title":"Chem. 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