The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic.

Synthesis, characterization, and applications of colloidal nanoparticles have been a prominent topic of current research interests within the last two decades. Available reports in the literature that describe the synthesis of colloidal nanoparticles are abundant with various degrees of reproducibility and simplicity. Moreover, different methods for the characterization of colloidal nanoparticle’s basic properties are employed, resulting in conflicting results in many cases. Herein, we describe “in detail” selected standard protocols for the synthesis, purification, and characterization of various types of colloidal inorganic nanoparticles including gold nanoparticles, silver nanoparticles, iron oxide nanoparticles, and quantum dots. This report consists of five main parts: The first and the second parts are dedicated to describing the synthesis of various types of hydrophobic and hydrophilic nanoparticles in organic solvents and in aqueous solutions, respectively. The third part describes surface modification of nanoparticles with a focus on ligand exchange reactions, to allow phase transfer of nanoparticles from aqueous to organic solvents and vice versa. The fourth and the fifth parts describe various general purification and characterization techniques used to purify and characterize nanoparticles, respectively. Collectively, this contribution does not aim to cover all available protocols in the literature to prepare inorganic nanoparticles but rather provides detailed synthetic procedures for important inorganic nanocrystals with a full description of their purification and characterization process.

Photodynamic therapy (PDT) uses photosensitizers (PSs) to treat some skin and eye diseases, and certain types of cancer. In this review, we summarise the strategies to design PSs and how they can be incorporated into different nanostructures.

Rare earth based nanostructures constitute a type of functional materials widely used and studied in the recent literature. The purpose of this review is to provide a general and comprehensive overview of the current state of the art, with special focus on the commonly employed synthesis methods and functionalization strategies of rare earth based nanoparticles and on their different bioimaging and biosensing applications. The luminescent (including downconversion, upconversion and permanent luminescence) and magnetic properties of rare earth based nanoparticles, as well as their ability to absorb X‐rays, will also be explained and connected with their luminescent, magnetic resonance and X‐ray computed tomography bioimaging applications, respectively. This review is not only restricted to nanoparticles, and recent advances reported for in other nanostructures containing rare earths, such as metal organic frameworks and lanthanide complexes conjugated with biological structures, will also be commented on.