This article reviews the classification of different lipid nanoparticles, and their preparation and characterization. Their applications in encapsulating and delivering hydrophobic drugs, hydrophilic drugs, and RNAs for different diseases and how lipid nanoparticles enable nanomedicine to address the challenges of blood–brain barrier, targeted delivery, and various routes of administration are also discussed .

Herein, various bioprinting methods are discussed briefly and then natural and synthetic polymers or hybrid biomaterials are presented with respect to their rheological, mechanical, and biological properties that are essential for successful 3D bioprinting. The future challenges and critical considerations concerning the translation of bioprinting technique are also discussed.

Properties such as size, surface charge, degradation rate, and the co-delivery of antigen and adjuvant all affect the immune responses of polymeric particle vaccines for infectious disease. A review of current and past literature reveals these effects vary with polymer type, antigen, adjuvant, and route of administration. Vaccine manufacturing methods also impact efficacy, scalability, and marketability.

Strengthening and stiffening tough double-network (DN) or polyampholyte (PA) hydrogels are a promising approach to fabricate synthetic hydrogels emulating the natural load-bearing tissues with elastic moduli in the MPa-to-GPa. Herein, several strategies for strengthening and stiffening the hydrogels are summarized, and their reinforcing and fracture mechanisms are outlined, providing future directions to develop hydrogels with desirable mechanical properties.

Air−liquid interface cultures are used to accurately mimic the human respiratory tract. Different cell types are combined to create a complex in vitro environment. Furthermore, the interaction with different pathogens such as viruses or bacteria can be simulated. Thereby, they represent a useful tool for drug testing and help reduce animal experimentation.