Cagdas Tunali, BesteTunali, DoganTurk, Mustafa2025-01-212025-01-2120212523-8027https://doi.org/10.1007/978-3-030-64410-9_3https://hdl.handle.net/20.500.12587/23416In this chapter, we first briefly explained the term nanotechnology and summarized the types and classification of nanoparticles while giving examples to important and most commonly used polymer-based nanoparticles such as polylactic acid-co-glycolic acid and polyethyleneimine also some other nanoparticles like quantum dots and magnetic nanoparticles. Then we classified the biomedical applications of nanoparticles according to their purpose of use; diagnosis (cancer diagnosis, detection of bacteria and viruses, and nanosensor applications), therapy (cancer therapeutics, antimicrobial agents, drug and gene delivery systems), and imaging (optical and magnetic resonance imaging). We explained the important issues for each application as best as we can while pointing out some key factors effecting the success of applications in a broader sense such as toxicity, releasing mechanism of target agents, and also transfection efficiency of applied nanoparticles. We hope that the reader can benefit from this chapter which is based on the most recent studies in their field. © 2021, The Author(s), under exclusive license to Springer Nature Switzerland AG.eninfo:eu-repo/semantics/closedAccessDelivery systems; Diagnosis; Imaging; Nanoparticle; Nanotechnology; TherapyBook Chapter416910.1007/978-3-030-64410-9_32-s2.0-85105630799Q2