Glass Leachables as a Nucleation Factor for Free Fatty Acid Particle Formation in Biopharmaceutical Formulations.

Surfactants are essential components in protein formulations protecting them against interfacial stress. One of the current industry-wide challenges is enzymatic degradation of parenteral surfactants such as polysorbate 20 (PS20) and polysorbate 80, which leads to the accumulation of free fatty acids (FFAs) potentially forming visible particles over the drug product shelf-life. While the concentration of FFAs can be quantified, the time point of particle formation remains unpredictable.

Adenovirus-Mimetic Nanoparticles: Sequential Ligand-Receptor Interplay as a Universal Tool for Enhanced / Cell Identification.

Viral infection patterns often rely on precisely coordinated sequences of distinct ligand-receptor interactions, leading in many cases to an outstanding target cell specificity. A successful mimicry of viral targeting strategies to create more site-specific nanoparticles (NPs) would therefore require particle-cell interactions to also be adequately controllable. In the present study, hetero-multivalent block-copolymer NPs present their attached ligands in a sterically controlled manner to create a sequential NP-cell interaction similar to the cell infiltration strategy of human adenovirus type 2.

Influenza A virus mimetic nanoparticles trigger selective cell uptake.

Poor target cell specificity is currently a major shortcoming of nanoparticles (NPs) used for biomedical applications. It causes significant material loss to off-target sites and poor availability at the intended delivery site. To overcome this limitation, we designed particles that identify cells in a virus-like manner.

Interaction of functionalized nanoparticles with serum proteins and its impact on colloidal stability and cargo leaching.

The majority of effort in the area of polymeric nanocarriers is aimed at providing controlled drug delivery in vivo. Therefore, it is essential to understand the delicate interplay of polymeric NPs with serum proteins in order to forecast their performance in a biological system. In this study, the interaction of serum proteins with functionalized polymeric colloids as a function of particle charge and hydrophobicity was investigated.

Ligand Density and Linker Length are Critical Factors for Multivalent Nanoparticle-Receptor Interactions.

Although there are a large number of studies available for the evaluation of the therapeutic efficacy of targeted polymeric nanoparticles, little is known about the critical attributes that can further influence their uptake into target cells. In this study, varying cRGD ligand densities (0-100% surface functionalization) were combined with different poly(ethylene glycol) (PEG) spacer lengths (2/3.5/5 kDa), and the specific receptor binding of targeted core-shell structured poly(lactic- co-glycolic acid)/poly(lactic acid)-PEG nanoparticles was evaluated using αβ integrin-overexpressing U87MG glioblastoma cells.

Fabrication of antibody-loaded microgels using microfluidics and thiol-ene photoclick chemistry.

Reducing burst effects, providing controlled release, and safeguarding biologics against degradation are a few of several highly attractive applications for microgels in the field of controlled release. However, the incorporation of proteins into microgels without impairing stability is highly challenging. In this proof of concept study, the combination of microfluidics and thiol-ene photoclick chemistry was evaluated for the fabrication of antibody-loaded microgels with narrow size distribution.

Controlled Antibody Release from Degradable Thermoresponsive Hydrogels Cross-Linked by Diels-Alder Chemistry.

Amine-modified four- and eight-armed poloxamines were prepared and subsequently functionalized with maleimide or furyl groups. Aqueous solutions of these polymers exhibited an immediate gelation at a temperature above 37 °C. Concomitantly, Diels-Alder reactions gradually cross-linked and cured the gels.