Cartilage Metabolism is Modulated by Synovial Fluid Through Metalloproteinase Activity.

Synovial fluid (SF) contains various cytokines that regulate chondrocyte metabolism and is dynamically associated with joint disease. The objective of this study was to investigate the effects of diluted normal SF on catabolic metabolism of articular cartilage under inflammatory conditions. For this purpose, SF was isolated from healthy bovine joints, diluted, and added to cartilage explant cultures stimulated with interleukin-1 (IL-1) for 12 days.

Targeted delivery of multifunctional magnetic nanoparticles.

Magnetic nanoparticles and their magnetofluorescent analogues have become important tools for in vivo imaging using magnetic resonance imaging and fluorescent optical methods. A number of monodisperse magnetic nanoparticle preparations have been developed over the last decade for angiogenesis imaging, cancer staging, tracking of immune cells (monocyte/macrophage, T cells) and for molecular and cellular targeting. Phage display and data mining have enabled the procurement of novel tissue- or receptor-specific peptides, while high-throughput screening of diversity-oriented synthesis libraries has identified small molecules that permit or prevent uptake by specific cell types.

"Clickable" nanoparticles for targeted imaging.

Nanomaterials functionalized with targeting ligands are increasingly recognized as useful materials for molecular imaging and drug delivery. Here we describe the development and validation of azide-alkyne reactions ("click chemistry") for the rapid, site-specific modification of nanoparticles with small molecules. The facile preparation of stable nanoparticles bearing azido or alkyne groups capable of reaction with their corresponding counterpart functionalized small molecules is demonstrated.

Development of nanoparticle libraries for biosensing.

Magnetic and magnetofluorescent nanoparticles have become important materials for biological applications especially for sensing, separation, and imaging. To achieve target specificity, these nanomaterials are often covalently modified with binding proteins such as antibodies or proteins. Here we report on the creation of nanoparticle libraries that achieve specificity through multivalent modification with small molecules.

Cell-specific targeting of nanoparticles by multivalent attachment of small molecules.

Nanomaterials with precise biological functions have considerable potential for use in biomedical applications. Here we investigate whether multivalent attachment of small molecules can increase specific binding affinity and reveal new biological properties of such nanomaterials. We describe the parallel synthesis of a library comprising 146 nanoparticles decorated with different synthetic small molecules.