{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T17:52:38Z","timestamp":1790963558577,"version":"4.1.0"},"reference-count":38,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T00:00:00Z","timestamp":1790899200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Biodegradable porous microspheres hold considerable promise as regenerative fillers, injectable biomaterials, tissue-engineering scaffolds, and drug-delivery carriers; however, how polymer properties and amphiphilic modification jointly influence pore formation remains insufficiently understood. In this study, porous microspheres composed of poly(D,L-lactide) (PDLLA), poly(L-lactide) (PLLA), poly(\u03b5-caprolactone) (PCL), and amphiphilic PEG-PDLLA were fabricated by a porogen-assisted solvent evaporation method, with PEG-PDLLA incorporated as an amphiphilic morphology-modifying polymer component. The relationships among polymer type and molecular weight, particle size, porogen incorporation, PEG-PDLLA incorporation, and microsphere morphology were evaluated using scanning electron microscopy, tapped-density porosity analysis, laser diffraction, Brunauer\u2013Emmett\u2013Teller (BET) surface area analysis, micro-computed tomography (Micro-CT), and differential scanning calorimetry (DSC). PDLLA exhibited the highest corrected density-derived porosity index (42.4%), followed by PLLA (30.9%) and PCL (13.6%). Smaller PDLLA microspheres showed higher corrected density-derived porosity, reaching 50.5% at a median particle diameter (D50) of 28.7 \u03bcm. PEG-PDLLA incorporation was associated with the formation of surface-open pores and heterogeneous internal architectures as well as increased nitrogen-accessible BET surface area and pore volume, with response exhibited in a polymer-dependent manner. Micro-CT showed differences in internal density distribution and architecture between PLLA and PLLA\/PEG-PDLLA microspheres, while DSC revealed polymer-dependent thermal characteristics without fundamentally altering the characteristic thermal transitions of the host polymers. Overall, porous microsphere formation was associated with polymer physicochemical properties, PEG-PDLLA-associated amphiphilic morphology modification, molecular weight, particle size, porogen incorporation, and emulsion\/solidification behavior. These findings provide a comparative framework for investigating formulation strategies for biodegradable porous microspheres with tunable architecture and surface accessibility for regenerative medicine and controlled drug-delivery applications.<\/jats:p>","DOI":"10.3390\/polym18192415","type":"journal-article","created":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T16:50:38Z","timestamp":1790959838000},"page":"2415","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Polymer-Dependent Morphology Development of Biodegradable Porous Microspheres with Amphiphilic PEG-PDLLA Incorporation"],"prefix":"10.3390","volume":"18","author":[{"given":"Jin Cheol","family":"Cho","sequence":"first","affiliation":[{"name":"R&D Center, VAIM Co., Ltd., 30, Techno 1-ro, Yuseong-gu, Daejeon 34016, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"}]},{"given":"Sun Woo","family":"Jung","sequence":"additional","affiliation":[{"name":"R&D Center, VAIM Co., Ltd., 30, Techno 1-ro, Yuseong-gu, Daejeon 34016, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"}]},{"given":"Gunpoong","family":"Kim","sequence":"additional","affiliation":[{"name":"R&D Center, VAIM Co., Ltd., 30, Techno 1-ro, Yuseong-gu, Daejeon 34016, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"conceptualization","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Lee, K.W.A., Chan, L.K.W., Lee, A.W.K., Lee, C.H., Wong, S.T.H., and Yi, K.H. 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