*3.2. Drug Delivery*

As mentioned above, various nanobiomaterials can be used for bone regeneration, prevention of infections, and osteointegration [480,481]. A nanoparticle that functions as carrier can stabilize the bioactive molecules through encapsulation [482], facilitating targeting cellular delivery and targeted drug release [483,484]. Nanospheres, tubes and capsules are widely accepted tools for targeted and sustained release drug delivery because of their small size and high specific surface area, which encapsulates the drug molecules and shows high reactivity to the surrounding tissues [485]. The materials selected for nanosphere fabrication depend on application principles and requirements. Some factors in this regard include size, drug characteristics, surface properties, biodegradability and biocompatibility of materials and drug release profile [486]. The 2D and 3D structures of scaffolds can be useful for the drug (poorly soluble drugs) loading purpose in tissue engineering (Figure 24).

**Figure 24.** Drugs and biomolecules loaded scaffold for tissue engineering.
