{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T18:28:29Z","timestamp":1790620109166,"version":"4.1.0"},"reference-count":43,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2024,5,14]],"date-time":"2024-05-14T00:00:00Z","timestamp":1715644800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Porous \u03b2-tricalcium phosphate (Ca3(PO4)2; \u03b2-TCP) was prepared via freeze-drying and the effects of this process on pore shapes and sizes were investigated. Various samples were prepared by freezing \u03b2-TCP slurries above a liquid nitrogen surface at \u2212180 \u00b0C with subsequent immersion in liquid nitrogen at \u2212196 \u00b0C. These materials were then dried under reduced pressure in a freeze-dryer, after which they were sintered with heating. Compared with conventional heat-based drying, the resulting pores were more spherical, which increased both the mechanical strength and porosity of the \u03b2-TCP. These materials had a wide range of pore sizes from 50 to 200 \u00b5m, with the mean and median values both approximately 100 \u00b5m regardless of the freeze-drying conditions. Mercury porosimetry data showed that the samples contained small, interconnected pores with sizes of 1.24 \u00b1 0.25 \u00b5m and macroscopic, interconnected pores of 25.8 \u00b1 4.7 \u00b5m in size. The effects of nonionic surfactants having different hydrophilic\/lipophilic balance (HLB) values on foaming and pore size were also investigated. Materials made with surfactants having lower HLB values exhibited smaller pores and lower porosity, whereas higher HLB surfactants gave higher porosity and slightly larger macropores. Even so, the pore diameter could not be readily controlled solely by adjusting the HLB value. The findings of this work indicated that high porosity (&gt;75%) and good compressive strength (&gt;2 MPa) can both be obtained in the same porous material and that foaming agents with HLB values between 12.0 and 13.5 were optimal.<\/jats:p>","DOI":"10.3390\/ijms25105363","type":"journal-article","created":{"date-parts":[[2024,5,14]],"date-time":"2024-05-14T10:26:36Z","timestamp":1715682396000},"page":"5363","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Characterization of Porous \u03b2-Type Tricalcium Phosphate Ceramics Formed via Physical Foaming with Freeze-Drying"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8965-6190","authenticated-orcid":false,"given":"Kazuaki","family":"Hashimoto","sequence":"first","affiliation":[{"name":"Department of Applied Chemistry, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino-shi 275-0016, Chiba, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroto","family":"Oikawa","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino-shi 275-0016, Chiba, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hirobumi","family":"Shibata","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino-shi 275-0016, Chiba, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"706","DOI":"10.1016\/j.jcms.2012.01.002","article-title":"Current trends and future perspectives of bone substitute materials\u2013From space holders to innovative biomaterials","volume":"40","author":"Kolk","year":"2012","journal-title":"J. Cranio Maxillofac. Surg."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1586\/17434440.3.1.49","article-title":"Bone graft substitutes","volume":"3","author":"Laurencin","year":"2006","journal-title":"Expert Rev. Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"S20","DOI":"10.1016\/j.injury.2005.07.029","article-title":"Bone substitutes: An update","volume":"36","author":"Giannoudis","year":"2005","journal-title":"Injury"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"101053","DOI":"10.1016\/j.pmatsci.2022.101053","article-title":"Improving biocompatibility for next generation of metallic implants","volume":"133","author":"Bandyopadhyay","year":"2023","journal-title":"Pro. Mater. Sci."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1465","DOI":"10.1016\/j.biomaterials.2009.11.050","article-title":"Bioceramics of calcium orthophosphates","volume":"31","author":"Dorozhkin","year":"2010","journal-title":"Biomaterials"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1089","DOI":"10.1023\/B:JMSM.0000004006.90399.b4","article-title":"Effect of micro- and macroporosity of bone substitutes on their mechanical properties and cellular response","volume":"14","author":"Bignon","year":"2003","journal-title":"J. Mater. Sci. Mater. Med."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.actbio.2020.06.022","article-title":"\u03b2-tricalcium phosphate for bone substitution: Synthesis and properties","volume":"113","author":"Bohner","year":"2020","journal-title":"Acta Biomater."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2493","DOI":"10.1002\/jbm.b.34049","article-title":"Hydoxyapatite\/beta-tricalcium phosphate biphasic ceramics asregenerative material for the repair of complex bone defects","volume":"106","author":"Owen","year":"2018","journal-title":"J. Biomed. Mater. Res. Part B Appl. Biomater."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1023\/A:1022872421333","article-title":"Biphasic calcium phosphate bioceramics: Preparation, properties and applications","volume":"14","author":"Legeros","year":"2003","journal-title":"J. Mater. Sci. Mater. Med."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.actbio.2017.01.076","article-title":"Biphasic calcium phosphate ceramics for bone reconstruction: A review of biological response","volume":"53","author":"Bouler","year":"2017","journal-title":"Acta Biomater."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"154","DOI":"10.1007\/s00113-003-0707-5","article-title":"Mechanical failure of porous hydroxyapatite ceramics 7.5 years after implantation in the proximal tibial","volume":"107","author":"Linhart","year":"2004","journal-title":"Unfallchirurg"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"94","DOI":"10.1002\/jbm.b.30136","article-title":"Comparison of hydroxyapatite and beta tricalcium phosphate as bone substitutes after excision of bone tumors","volume":"72","author":"Ogose","year":"2005","journal-title":"J. Biomed. Mater. Res. Part B Appl. Biomater."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1002\/jor.1100030306","article-title":"Comparative study of porous hydroxyapatite and tricalcium phosphate as bone substitute","volume":"3","author":"Shimazaki","year":"1985","journal-title":"J. Ortho. Res."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1186\/s40902-023-00390-w","article-title":"Efficacy of pure beta tricalcium phosphate graft in dentoalveolar surgery: A retrospective evaluation based on serial radiographic images","volume":"45","author":"Choi","year":"2023","journal-title":"Maxillofac. Plast. Reconstr. Surg."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"106","DOI":"10.1016\/j.mattod.2017.02.002","article-title":"Characterization and distribution of mechanically competent mineralized tissue in micropores of \u03b2-tricalcium phosphate bone substitutes","volume":"20","author":"Bohner","year":"2017","journal-title":"Mater. Today"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"2175","DOI":"10.1016\/j.biomaterials.2009.01.008","article-title":"Can bioactivity be tested in vitro with SBF solution?","volume":"30","author":"Bohner","year":"2009","journal-title":"Biomaterials"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"5600","DOI":"10.1016\/j.biomaterials.2005.02.026","article-title":"Bone formation and resorption of highly purified \u03b2-tricalcium phosphate in the rat femoral condyle","volume":"26","author":"Kondo","year":"2005","journal-title":"Biomaterials"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"13614","DOI":"10.1073\/pnas.1003600107","article-title":"Osteoinductive ceramics as a synthetic alternative to autologous bone grafting","volume":"107","author":"Yuan","year":"2010","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"4493","DOI":"10.1016\/S0142-9612(02)00193-X","article-title":"Promotion of bone formation using highly pure porous \u03b2-TCP combined with bone marrow-derived osteoprogenitor cells","volume":"23","author":"Dong","year":"2002","journal-title":"Biomaterials"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"3569","DOI":"10.1016\/j.biomaterials.2003.10.032","article-title":"Theoretical model to determine the effects of geometrical factors on the resorption of calcium phosphate bone substitutes","volume":"25","author":"Bohner","year":"2004","journal-title":"Biomaterials"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"4845","DOI":"10.1016\/j.actbio.2012.07.040","article-title":"Micropourous calcium phosphate ceramics as tissue engineering scaffolds for the repair of osteochondral defect: Biomechanical results","volume":"9","author":"Mayr","year":"2013","journal-title":"Acta Biomater."},{"key":"ref_22","first-page":"272","article-title":"Absorbable implants in sport medicine and arthroscopic surgery: A narrative review of recent development","volume":"31","author":"Huang","year":"2024","journal-title":"Bioact. Mater."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"3552","DOI":"10.1016\/j.biomaterials.2010.01.052","article-title":"Multiscale osteointegration as a new paradigm for the design of calcium phosphate scaffolds for bone regeneration","volume":"31","author":"Levengood","year":"2010","journal-title":"Biomaterials"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"9223","DOI":"10.1021\/acsami.8b22041","article-title":"Engineering Porous \u03b2-Tricalcium Phosphate (\u03b2-TCP) Scaffolds with Multiple Channels to Promote Cell Migration, Proliferation, and Angiogenesis","volume":"11","author":"Wang","year":"2019","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"885","DOI":"10.1007\/s12257-019-0248-6","article-title":"Improvement of Bone Formation in Rats with Calvarial Defects by Modulating the Pore Size of Tricalcium Phosphate Scaffolds","volume":"24","author":"Park","year":"2019","journal-title":"Biotechnol. Bioproc."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"182","DOI":"10.1007\/s11051-015-2985-6","article-title":"Modulation of mesenchymal stem cell behavior by nano- and micro-sized \u03b2-tricalcium phosphate particles in suspension and composite structutes","volume":"17","author":"Smoak","year":"2015","journal-title":"J. Nanopart. Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"435","DOI":"10.1016\/j.actbio.2014.09.028","article-title":"Enhanced effect of \u03b2-tricalcium phosphate phase on neovascularization of porous calcium phosphate ceramics: In vitro and in vivo evidence","volume":"11","author":"Chen","year":"2015","journal-title":"Acta Biomater."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"18400","DOI":"10.1016\/j.ceramint.2018.07.056","article-title":"Techniques for fabrication and construction of three-dimensional bioceramic scaffolds: Effect on pores size, porosity and compressive strength","volume":"44","author":"Darus","year":"2018","journal-title":"Ceram. Inter."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"433","DOI":"10.1134\/S0036029523040122","article-title":"Mechanical Properties of Ca3(PO4)2-Based Macroporous Bioceramics","volume":"2023","author":"Larionov","year":"2023","journal-title":"Russ. Metall."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1016\/j.colsurfa.2016.12.004","article-title":"The Gibbs-Marangoni stress and non DLVO forces are equally important for modeling bubble coalescence in salt solutions","volume":"515","author":"Firouzi","year":"2017","journal-title":"Colloids Surf. A Physicochem. Eng. Asp."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"92","DOI":"10.1016\/j.colsurfa.2019.01.062","article-title":"Effect of water-soluble polymers on the performance of dust-suppression foams: Wettability, surface viscosity and stability","volume":"568","author":"Wang","year":"2019","journal-title":"Colloids Surf. A Physicochem. Eng. Asp."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Clint, J.H. (1992). Surfactant Aggregation, Blackie & Son. Chapter 11.","DOI":"10.1007\/978-94-011-2272-6"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.cis.2015.07.006","article-title":"Modification of the Young\u2013Laplace equation and prediction of bubble interface in the presence of nanoparticles","volume":"225","author":"Vafaei","year":"2015","journal-title":"Adv. Colloid Interface Sci."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Dufner, L., O\u00dfwald, B., Eberspaecher, J., Riedel, B., Kling, C., Kern, F., and Seidenstuecker, M. (2023). Adjustment of Micro- and Macroporosity of \u00df-TCP Scaffolds Using Solid-Stabilized Foams as Bone Replacement. Bioengineering, 10.","DOI":"10.3390\/bioengineering10020256"},{"key":"ref_35","first-page":"155","article-title":"Fabrication of Porous \u03b2-Tricalcium Phosphate Using Cellulose-Nano-Fiber","volume":"27","author":"Sasaki","year":"2020","journal-title":"J. Soc. Inorg. Mater. Jpn."},{"key":"ref_36","first-page":"250","article-title":"Preparation and Evaluation of Porous \u03b2-Type Tricalcium Phosphate by Physical Foaming Method Using Acetylated Cellulose Nanofibers","volume":"29","author":"Mochida","year":"2022","journal-title":"J. Soc. Inorg. Mater. Jpn."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"32","DOI":"10.3363\/prb.38.32","article-title":"Preparation of porous \u03b2-tricalcium phosphate by foaming method using cellulose nanofiber with different manufacturing methods as foam stabilizer","volume":"38","author":"Toyota","year":"2022","journal-title":"Phosphorus Res. Bull."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"275","DOI":"10.2109\/jcersj2.24017","article-title":"Characterization of Porous \u03b2-Tricalcium Phosphate Fabricated by Physical Foaming with a Nonionic Surfactant: Effect of Adding a Thicken","volume":"132","author":"Hashimoto","year":"2024","journal-title":"J. Ceram. Soc. Jpn."},{"key":"ref_39","first-page":"249","article-title":"Calculation of HLB Values of Non-Ionic Surfactants","volume":"5","author":"Griffin","year":"1954","journal-title":"J. Soc. Cosmet. Chem."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1023\/A:1008961816208","article-title":"Characterization of the transformation from calcium-deficient apatite to \u03b2-tricalcium phosphate","volume":"11","author":"Gibson","year":"2000","journal-title":"J. Mater. Sci. Mater. Med."},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Tan, M., Mei, J., and Xie, J. (2021). The Formation and Control of Ice Crystal and Its Impact on the Quality of Frozen Aquatic Products: A Review. Crystals, 11.","DOI":"10.3390\/cryst11010068"},{"key":"ref_42","unstructured":"(1998). Test Methods for Density and Apparent Porosity of Fine Ceramics (Standard No. JISR 1634)."},{"key":"ref_43","unstructured":"(2003). Testing Methods for Compressive Strength of Fine Ceramics (Standard No. JIS R 1608:2003)."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/25\/10\/5363\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T14:42:17Z","timestamp":1760107337000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/25\/10\/5363"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,5,14]]},"references-count":43,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2024,5]]}},"alternative-id":["ijms25105363"],"URL":"https:\/\/doi.org\/10.3390\/ijms25105363","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,5,14]]}}}