The authors of this book have studied nanoprobe‐based diagnosis and therapy of diseases over ten years. According to the concept of functional modification of nanomaterials, they have carried out a series of research on the design, construction, and performance regulation of TiO₂ nanoprobes in theranostics of cancers. For example, they prepared Janus structure of TiO₂–Fe₃O₄ nanoprobes for magnetic resonance imaging (MRI)‐visualized photodynamic therapy (PDT) of breast cancer, developed TiO₂–upconversion nanoprobes for near‐infrared‐triggered PDT/chemotherapy of breast cancer, and explored novel black TiO₂ nanoprobes for photothermal therapy (PTT) of breast cancer and MRI‐visualized PTT of pancreatic cancer stem cells, acting as substrate of surface‐enhanced Raman spectroscopy (SERS) for the detection of drug‐resistant cancer cells. Based on their study of TiO₂ nanoprobes in the past ten years, and reference to the related works of peers, the authors decide to write this book on the application of TiO₂ nanoparticles in nanobiotechnology, and nanomedicine. This book not only summarizes the research progress of TiO₂ but also points out the existent problems in TiO₂ biomedical applications and the potential development directions in future.

This book includes seven chapters. Chapter 1 briefly introduces the properties, preparation methods, and applications of TiO₂ nanoparticles in nanomedicine and nanobiotechnology. The properties of TiO₂ nanoparticles are the intrinsic reason for their applications. Understanding the preparation methods will help people to improve the performances of TiO₂ nanoparticles. Chapter 2 summarizes the pathway, distribution, clearance, ultimate fate of TiO₂ products in vivo, and the dose‐dependent potential toxicity, as well as the interactions between TiO₂ and cells, which will help people to improve material design and reduce their toxicity. Chapter 3 reviews the latest research progress of TiO₂‐based antimicrobial application, including how to improve the photocatalytic activity of TiO₂ by non‐metal doping such as nitrogen and carbon, as well as metal doping with nickel and neodymium, which achieves visible light‐triggered high efficiency of antimicrobial activity. Chapter 4 introduces the application of TiO₂ as SERS substrate in biosensors and focuses on the SERS enhancement mechanism of TiO₂ nanoparticles. Chapter 5 mainly reviews white TiO₂ nanoparticles and their nanocomposites with novel structures and properties in cancer theranostics, such as ultraviolet or near‐infrared light‐stimulated PDT, ultrasound‐triggered sonodynamic therapy (SDT), and drug delivery. Chapter 6 summarizes the properties, preparation, and research progress of black TiO₂ nanoparticles in cancer theranostics, including black TiO₂ with the functions of PTT, PDT, SDT, drug carriers, and photothermal and photoacoustic imaging. Chapter 7 reviews the application of TiO₂ nanoparticles in neurodegenerative diseases.

The authors hope that the publication of this book will help readers to fully understand the preparation, performance regulation, latest research progress in the field of nanomedicine, and the problems hindering the further application of TiO₂ nanoparticles. In this regard, it will encourage readers to focus on and solve these problems in future, promote the clinical application of TiO₂ in nanomedicine, and provide more efficient safe treatments for patients. Finally, the editors of this book would like to thank all the authors in each chapter for their hard work in discussion and writing this book, and they appreciate the support of talent policies and the funding of various scientific and technological projects. They also thank the authors of the references whose figures are reused in this book.

September 20, 2019