{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,17]],"date-time":"2026-10-17T23:17:28Z","timestamp":1792279048944,"version":"4.4.0"},"reference-count":40,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2022,11,3]],"date-time":"2022-11-03T00:00:00Z","timestamp":1667433600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Large Groups Project","award":["RGP. 2\/93\/43"],"award-info":[{"award-number":["RGP. 2\/93\/43"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>For the creation of healable cement concrete matrix, microbial self-healing solutions are significantly more creative and potentially successful. The current study investigates whether gram-positive \u201cBacillus subtilis\u201d (B. subtilis) microorganisms can effectively repair structural and non-structural cracks caused at the nano- and microscale. By creating an effective immobilization strategy in a coherent manner, the primary challenge regarding the viability of such microbes in a concrete mixture atmosphere has been successfully fulfilled. The iron oxide nanoparticles were synthesized. The examined immobilizing medium was the iron oxide nanoparticles, confirmed using different techniques (XRD, SEM, EDX, TGA, and FTIR). By measuring the average compressive strength of the samples (ASTM C109) and evaluating healing, the impact of triggered B. subtilis bacteria immobilized on iron oxide nanoparticles was examined. The compressive strength recovery of cracked samples following a therapeutic interval of 28 days served as a mechanical indicator of the healing process. In order to accurately correlate the recovery performance as a measure of crack healing duration, the pre-cracking load was set at 80% of the ultimate compressive stress, or \u201cf c,\u201d and the period of crack healing was maintained at 28 days. According to the findings, B. subtilis bacteria greatly enhanced the compressive strength and speed up the healing process in cracked cement concrete mixture. The iron oxide nanoparticles were proven to be the best immobilizer for keeping B. subtilis germs alive until the formation of fractures. The bacterial activity-driven calcite deposition in the generated nano-\/micro-cracks was supported by micrographic and chemical investigations (XRD, FTIR, SEM, and EDX).<\/jats:p>","DOI":"10.3390\/ma15217731","type":"journal-article","created":{"date-parts":[[2022,11,3]],"date-time":"2022-11-03T03:53:07Z","timestamp":1667447587000},"page":"7731","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":48,"title":["Self-Healing Bio-Concrete Using Bacillus subtilis Encapsulated in Iron Oxide Nanoparticles"],"prefix":"10.3390","volume":"15","author":[{"given":"Faisal","family":"Mahmood","sequence":"first","affiliation":[{"name":"Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus, Abbottabad 22060, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2766-052X","authenticated-orcid":false,"given":"Sardar","family":"Kashif Ur Rehman","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus, Abbottabad 22060, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5968-6623","authenticated-orcid":false,"given":"Mohammed","family":"Jameel","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, King Khalid University, Abha 61421, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0931-1089","authenticated-orcid":false,"given":"Nadia","family":"Riaz","sequence":"additional","affiliation":[{"name":"Department of Environmental Sciences, COMSATS University Islamabad, Abbottabad Campus, Abbottabad 22060, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5478-9324","authenticated-orcid":false,"given":"Muhammad Faisal","family":"Javed","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus, Abbottabad 22060, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdelatif","family":"Salmi","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, College of Engineering in Alkharj, Prince Sattam bin Abdulaziz University, Alkharj 16273, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Youssef Ahmed","family":"Awad","sequence":"additional","affiliation":[{"name":"Structural Engineering Department, Faculty of Engineering and Technology, Future University in Egypt, New Cairo 11835, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"9895","DOI":"10.1007\/s00253-016-7701-7","article-title":"Induced calcium carbonate precipitation using Bacillus species","volume":"100","author":"Seifan","year":"2016","journal-title":"Appl. Microbiol. Biotechnol."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Luhar, S., Luhar, I., and Shaikh, F.U.A. (2022). A Review on the Performance Evaluation of Autonomous Self-Healing Bacterial Concrete: Mechanisms, Strength, Durability, and Microstructural Properties. J. Compos. Sci., 6.","DOI":"10.3390\/jcs6010023"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"880","DOI":"10.1080\/15732479.2012.761248","article-title":"Lifetime seismic performance of concrete bridges exposed to corrosion","volume":"10","author":"Biondini","year":"2014","journal-title":"Struct. Infrastruct. Eng."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1016\/j.conbuildmat.2014.01.039","article-title":"Assessment of the sustainability potential of concrete and concrete structures considering their environmental impact, performance and lifetime","volume":"67","author":"Haist","year":"2014","journal-title":"Constr. Build. Mater."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2104798","DOI":"10.1002\/adma.202104798","article-title":"Processing of Self-Healing Polymers for Soft Robotics","volume":"34","author":"Roels","year":"2022","journal-title":"Adv. Mater."},{"key":"ref_6","unstructured":"Palmer, F. (2009). Using Emergent Technologies to Develop Sustainable Architectural Composites, Auckland University of Technology."},{"key":"ref_7","unstructured":"Virmani, Y.P., and Clemena, G.G. (1998). Corrosion Protection: Concrete Bridges, Federal Highway Administration."},{"key":"ref_8","unstructured":"Tannous, F. (1997). Durability of AR Non-Metallic Reinforcement Bars and Prestressing Tendons. [Ph.D Thesis, The University of Arizona]."},{"key":"ref_9","first-page":"12","article-title":"Nondestructive surface measurement of corrosion of reinforcing steel in concrete","volume":"21","author":"Mancio","year":"2004","journal-title":"Can. Civ. Eng."},{"key":"ref_10","first-page":"615","article-title":"Effect of sustained load and environment on long-term tensile properties of glass fiber-reinforced polymer reinforcing bars","volume":"102","author":"Nkurunziza","year":"2005","journal-title":"ACI Struct. J."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1016\/j.cemconres.2009.08.025","article-title":"Use of bacteria to repair cracks in concrete","volume":"40","author":"Verstraete","year":"2010","journal-title":"Cem. Concrete Res."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1689","DOI":"10.1098\/rsta.2009.0020","article-title":"Self-healing behaviour in man-made engineering materials: Bioinspired but taking into account their intrinsic character","volume":"367","author":"Jonkers","year":"2009","journal-title":"Philos. Trans. R. Soc. A: Math. Phys. Eng. Sci."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"119258","DOI":"10.1016\/j.conbuildmat.2020.119258","article-title":"Insight into the role of microbial calcium carbonate and the factors involved in self-healing concrete","volume":"254","author":"Algaifi","year":"2020","journal-title":"Constr. Build. Mater."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1246","DOI":"10.1016\/j.matpr.2020.08.765","article-title":"Self healing concrete based on different bacteria: A review","volume":"43","author":"Jogi","year":"2020","journal-title":"Mater. Today Proc."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"4368","DOI":"10.1007\/s12205-019-1661-2","article-title":"An experimental study on effects of bacterial strain combination in fibre concrete and self-healing efficiency","volume":"23","author":"Ganesh","year":"2019","journal-title":"KSCE J. Civ. Eng."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1005","DOI":"10.1016\/j.cemconres.2008.03.005","article-title":"Bacterial carbonate precipitation improves the durability of cementitious materials","volume":"38","author":"Debrouwer","year":"2008","journal-title":"Cem. Concrete Res."},{"key":"ref_17","first-page":"392","article-title":"A biological approach to enhance strength and durability in concrete structures","volume":"4","author":"Reddy","year":"2012","journal-title":"Int. J. Adv. Eng. Technol."},{"key":"ref_18","first-page":"3","article-title":"Remediation of concrete using micro-organisms","volume":"98","author":"Ramachandran","year":"2001","journal-title":"ACI Mater. J.-Am. Concrete Inst."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"118","DOI":"10.1016\/j.ecoleng.2009.02.006","article-title":"Microbial carbonate precipitation in construction materials: A review","volume":"36","author":"Verstraete","year":"2010","journal-title":"Ecol. Eng."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"4659","DOI":"10.1128\/AEM.01349-14","article-title":"Formate oxidation-driven calcium carbonate precipitation by Methylocystis parvus OBBP","volume":"80","author":"Ganendra","year":"2014","journal-title":"Appl. Environ. Microbiol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2591","DOI":"10.1007\/s00253-016-7316-z","article-title":"Bioconcrete: Next generation of self-healing concrete","volume":"100","author":"Seifan","year":"2016","journal-title":"Appl. Microbiol. Biotechnol."},{"key":"ref_22","first-page":"45","article-title":"Bioengineered Concrete-A Sustainable Self-Healing Construction Material","volume":"2","author":"Rao","year":"2013","journal-title":"Res. J. Eng. Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"567","DOI":"10.1007\/s10295-011-1037-1","article-title":"Diatomaceous earth as a protective vehicle for bacteria applied for self-healing concrete","volume":"39","author":"Wang","year":"2012","journal-title":"J. Ind. Microbiol. Biotechnol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"816","DOI":"10.1016\/j.conbuildmat.2018.08.218","article-title":"Numerical modeling for crack self-healing concrete by microbial calcium carbonate","volume":"189","author":"Algaifi","year":"2018","journal-title":"Constr. Build. Mater."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1016\/j.jcrysgro.2012.09.025","article-title":"Substrate effect on surface adhesion\/crystallisation of calcium carbonate","volume":"363","author":"Cheong","year":"2013","journal-title":"J. Cryst. Growth"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1179\/095066003225005836","article-title":"Calcium carbonate in biomineralisation and biomimetic chemistry","volume":"48","author":"Meldrum","year":"2003","journal-title":"Int. Mater. Rev."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1202","DOI":"10.1002\/suco.201700235","article-title":"Effect of parameters on the compressive strength of fly ash based geopolymer concrete","volume":"19","author":"Chithambaram","year":"2018","journal-title":"Struct. Concrete"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1016\/j.cej.2012.01.052","article-title":"Photodegradation of Orange II under visible light using Cu\u2013Ni\/TiO2: Effect of calcination temperature","volume":"185","author":"Riaz","year":"2012","journal-title":"Chem. Eng. J."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"4489","DOI":"10.1007\/s00253-018-8913-9","article-title":"Mechanical properties of bio self-healing concrete containing immobilized bacteria with iron oxide nanoparticles","volume":"102","author":"Seifan","year":"2018","journal-title":"Appl. Microbiol. Biotechnol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1111\/raq.12033","article-title":"Probiotics in aquaculture: A current assessment","volume":"6","year":"2014","journal-title":"Rev. Aquac."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"105030","DOI":"10.1016\/j.yrtph.2021.105030","article-title":"Safety evaluation of food enzymes produced by a safe strain lineage of Bacillus subtilis","volume":"126","author":"Galano","year":"2021","journal-title":"Regul. Toxicol. Pharmacol."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Dhiman, N.K., Sidhu, N., Agnihotri, S., Mukherjee, A., and Reddy, M.S. (2022). Role of nanomaterials in protecting building materials from degradation and deterioration. Biodegradation and Biodeterioration at the Nanoscale, Elsevier.","DOI":"10.1016\/B978-0-12-823970-4.00024-5"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"336","DOI":"10.7763\/IJESD.2013.V4.366","article-title":"Synthesis and properties of Fe3O4 nanoparticles by co-precipitation method to removal procion dye","volume":"4","author":"Hariani","year":"2013","journal-title":"Int. J. Environ. Sci. Dev."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"793","DOI":"10.1016\/j.spmi.2012.07.009","article-title":"Sol\u2013gel synthesis of 8 nm magnetite (Fe3O4) nanoparticles and their magnetic properties","volume":"52","author":"Lemine","year":"2012","journal-title":"Superlattices Microstruct."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"632","DOI":"10.1016\/j.proeng.2011.12.498","article-title":"Synthesis of Fe3O4 nanoparticles and their magnetic properties","volume":"27","author":"Wei","year":"2012","journal-title":"Procedia Eng."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"599","DOI":"10.1016\/j.jallcom.2019.03.414","article-title":"Hydrothermal synthesis of hematite (\u03b1-Fe2O3) nanoparticle forms: Synthesis conditions, structure, particle shape analysis, cytotoxicity and magnetic properties","volume":"792","author":"Tadic","year":"2019","journal-title":"J. Alloys Compounds"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1537","DOI":"10.1016\/0008-8846(96)00148-2","article-title":"Relative strength, pozzolanic activity and cement hydration in superplasticised metakaolin concrete","volume":"26","author":"Wild","year":"1996","journal-title":"Cem. Concrete Res."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1039\/C0NR00589D","article-title":"The kinetics and mechanisms of amorphous calcium carbonate (ACC) crystallization to calcite, via vaterite","volume":"3","author":"Shaw","year":"2011","journal-title":"Nanoscale"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1264\/jsme2.2000.161","article-title":"Identification of Early bacillus-induced crystals in vitro using Fourier transform infrared spectroscopy","volume":"15","author":"Adolphe","year":"2000","journal-title":"Microbes Environ."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"3262","DOI":"10.1002\/chem.200600825","article-title":"In vitro study of magnesium-calcite biomineralization in the skeletal materials of the seastar Pisaster giganteus","volume":"13","author":"Gayathri","year":"2007","journal-title":"Chem.\u2014Eur. J."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/15\/21\/7731\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:09:42Z","timestamp":1760144982000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/15\/21\/7731"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,11,3]]},"references-count":40,"journal-issue":{"issue":"21","published-online":{"date-parts":[[2022,11]]}},"alternative-id":["ma15217731"],"URL":"https:\/\/doi.org\/10.3390\/ma15217731","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,11,3]]}}}