Display omitted •Definition, types, synthetic routes of nanoparticles and their applications.•Recent trends in nanomaterial-based bioimaging: early detection of diseases.•Nanomaterial-based biosensors enabled early sensing of diseases like cancer.•Nanoparticles as future drug with their antimicrobial and antibiofilm activities.•Revolutionary role of nanoparticle-based therapeutics in cancer treatment. Biomedical applications of nanomaterials have received considerable attention and interest from many researchers over the past decade due to the key role they can play in enhancing public health. Different types of nanomaterials possess both diagnostic and therapeutic potential owing to their outstanding properties compared to their bulk counterparts. Herein, we present, analyze and provide significant insights and recent advances about the promising biomedical applications of nanoparticles including bioimaging of biological environments and its role as a significant tool for early detection of many diseases with respect to traditional means, explaining their types and limitations. In addition, different types of nanoparticles acting as effective bio-sensors and detectors of our body have been analyzed. Moreover, the therapeutic potential of different types of nanoparticles and their attractive antimicrobial effects allowing them to act as powerful and new drug substitutes against multi-drug resistant bacteria and pathogenic fungi. Finally, we introduce some nanoparticles as powerful antioxidants and promising candidates in cancer therapeutics. We conclude that this review can give up-to-date information about various biomedical applications of nanoparticles and will be of great value and interest to researchers and scientists of materials science, biology, chemistry, and medicine.