Review Borophene-based biomedical applications: Status and future challenges Yanhong Duo a,b,1 , Zhongjian Xie d,1 , Lude Wang a,1 , Nasir Mahmood Abbasi f , Tingqiang Yang a , Zihuang Li c,⇑ , Guoxin Hu e,⇑ , Han Zhang a,⇑ a International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China b Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm 17177, Sweden c Department of Radiation Oncology, The 2nd Clinical medical College (Shenzhen People’s Hospital) of Jinan University, Shenzhen 518020, China d Shenzhen International Institute for Biomedical Research, Shenzhen, China e Department of Infectious Diseases, Peking University Shenzhen Hospital, Shenzhen 518036, China f School of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China article info Article history: Received 7 April 2020 Received in revised form 5 August 2020 Accepted 10 August 2020 Keywords: Borophene Nanomedicine Biocompatible Biodegradable abstract Borophene is composed purely of boron atoms and arranged in a hexagonal structure with conventional covalent bonds between each boron atom. Recently, researchers have shown a burgeoning research inter- est in borophene, not only regarding industrial applications but also in the field of biomedicine. Here, we provide an up-to-date summary of the recent advances in borophene-based nano-medicine. We firstly introduce the structural, mechanical, electrical, optical, thermal conductivity, biocompatibility, toxicity, photothermal and photodynamic effects of borophene. Subsequently, we fully discuss the differences between borophene, MXenes and graphene synthesized using traditional methods. Finally, we review the emerging use of borophenes as biosensors and therapeutics. We used strengths, weaknesses, oppor- tunities, threats (SWOT) analysis to assess both the current and future marketing potential of 2D based nanomaterials in cancer therapeutics. Current challenges and future perspectives for the use of boro- phene are additionally discussed. Ó 2020 Elsevier B.V. All rights reserved. Contents 1. Introduction ........................................................................................................... 2 2. Fabrication and surface functionalization .................................................................................... 3 2.1. Preparation of MXene .............................................................................................. 3 2.2. Preparation of graphene ............................................................................................ 3 2.3. Preparation of borophene ........................................................................................... 3 2.4. Surface functionalization ........................................................................................... 4 3. Structural properties of borophene ......................................................................................... 4 3.1. Boron ........................................................................................................... 4 3.2. Borophene ....................................................................................................... 4 4. Physical properties of borophene .......................................................................................... 5 4.1. Mechanical properties .............................................................................................. 5 4.2. Electronic properties ............................................................................................... 5 4.3. Magnetic properties ............................................................................................... 6 4.4. Thermal conductivity .............................................................................................. 6 4.5. Biocompatibility and toxic effects .................................................................................... 7 5. Biomedical applications of borophene ...................................................................................... 7 https://doi.org/10.1016/j.ccr.2020.213549 0010-8545/Ó 2020 Elsevier B.V. All rights reserved. Abbreviations: B, Borophene; QDs, quantum dots; NSs, nanosheets; NPs, nanoparticles; NIR, near-infrared; PTCE, photothermal conversion efficiency; PTT, photothermal therapy; PDT, photodynamic therapy; ROS, reactive oxygen species; EPR, enhanced permeability and retention; DDSs, drug delivery systems. ⇑ Corresponding authors. E-mail addresses: li.zihuang@szhospital.com (Z. Li), huguoxin8228@sina.com (G. Hu), hzhang@szu.edu.cn (H. Zhang). 1 These authors contributed equally. Coordination Chemistry Reviews 427 (2021) 213549 Contents lists available at ScienceDirect Coordination Chemistry Reviews journal homepage: www.elsevier.com/locate/ccr