Surface properties ofperfluorodecalin–containing liquid/liquid systems: The influence of Pluronic F-68 dissolved in the aqueous phase

Identification of film-based formulations that move mRNA lipid nanoparticles out of the freezer

COVID-19 vaccines consisting of mRNA lipid nanoparticles (LNPs) encoding the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein antigen protected millions of people from severe disease; however, they must be stored frozen prior to use. The objective of this study was to evaluate the compatibility and stability of mRNA LNPs within a polymer-based film matrix. An optimized formulation of polymer base, glycerol, surfactants, and PEGylated lipid that prevents damage to the LNP due to physical changes during the film-forming process (osmotic stress, surface tension, spatial stress, and water loss) was identified. Surfactants added to LNP stock prior to mixing with other film components contributed to this effect. Formulations prepared at pH ≥ 8.5 extended transfection efficiency beyond 4 weeks at 4°C when combined with known nucleic acid stabilizers. mRNA LNPs were most stable in films when manufactured in an environment of ∼50% relative humidity. The optimized formulation offers 16-week stability at 4°C.

Poloxamer-Based Mixed Micelles Loaded with Thymol or Eugenol for Topical Applications

Poloxamers (P184, P188, and P407) have been investigated as the carrier system for eugenol or thymol. A synergic effect of mixed Poloxamers was proved by enhanced micellar parameters, with a lower critical micelle concentration (about 0.06 mM) and the highest surface adsorption of 9 × 10-7 mol m-2 for P188/P407. Dynamic light scattering revealed a decrease in micellar size after loading with biomolecules. Three mathematical models were applied to study the release kinetics, of which Korsmeyer-Peppas was the best fitted model. Higher relative release was observed for Poloxamer/eugenol samples, up to a value of 0.8. Poloxamer micelles with thymol were highly influential in bacterial reduction. Single P407/eugenol micelles proved to be bacteriostatic for up to 6 h for S. aureus or up to 48 h for E. coli. Mixed micelles were confirmed to have prolonged bacteriostatic activity for up to 72 h against both bacteria. This trend was also proven by the modified Gompertz model. An optimized P188/P407/eugenol micelle was successfully used as a model system for release study with a particle size of less than 30 nm and high encapsulation efficiency surpassing 90%. The developed mixed micelles were proved to have antibiofilm activity, and thus they provide an innovative approach for controlled release with potential in topical applications.

Peptonics: A new family of cell-protecting surfactants for the recombinant expression of therapeutic proteins in mammalian cell cultures

Polymer surfactants are key components of cell culture media as they prevent mechanical damage during fermentation in stirred bioreactors. Among cell-protecting surfactants, Pluronics are widely utilized in biomanufacturing to ensure high cell viability and productivity. Monodispersity of monomer sequence and length is critical for the effectiveness of Pluronics-since minor deviations can damage the cells-but is challenging to achieve due to the stochastic nature of polymerization. Responding to this challenge, this study introduces Peptonics, a novel family of peptide and peptoid surfactants whose monomer composition and sequence are designed to achieve high cell viability and productivity at a fraction of chain length and cost of Pluronics. A designed ensemble of Peptonics was initially characterized via light scattering and tensiometry to select sequences whose phase behavior and tensioactivity align with those of Pluronics. Selected sequences were evaluated as cell-protecting surfactants using Chinese hamster ovary (CHO) cells expressing therapeutic monoclonal antibodies (mAb). Peptonics IH-T1010, ih-T1010, and ih-T1020 afforded high cell density (up to 3 × 107 cells mL-1 ) and viability (up to 95% within 10 days of culture), while reducing the accumulation of ammonia (a toxic metabolite) by ≈10% compared to Pluronic F-68. Improved cell viability afforded high mAb titer (up to 5.5 mg mL-1 ) and extended the production window beyond 14 days; notably, Peptonic IH-T1020 decreased mAb fragmentation and aggregation ≈5%, and lowered the titer of host cell proteins by 16% compared to Pluronic F-68. These features can improve significantly the purification of mAbs, thus increasing their availability at a lower cost to patients.

Direct and Reverse Pluronic Micelles: Design and Characterization of Promising Drug Delivery Nanosystems

Pluronics are a family of amphiphilic block copolymers broadly explored in the pharmaceutical field. Under certain conditions, Pluronics self-assemble in different structures including nanosized direct and reverse micelles. This review provides an overview about the main parameters affecting the micellization process of Pluronics, such as polymer length, fragments distribution within the chain, solvents, additives and loading of cargo. Furthermore, it offers a guide about the most common techniques used to characterize the structure and properties of the micelles. Finally, it presents up-to-date approaches to improve the stability and drug loading of Pluronic micelles. Special attention is paid to reverse Pluronics and reverse micelles, currently underexplored in the literature. Pluronic micelles present a bright future as drug delivery agents. A smart design and thorough characterization will improve the transfer to clinical applications.

Baicalin encapsulating lipid-surfactant conjugate based nanomicelles: Preparation, characterization and anticancer activity

Lung cancer is one of the most common malignant tumors and emerged as one of the leading causes of cancer-related death worldwide. Surgical resection can be a curative treatment for early stage but the most of lung cancer patients are diagnosed at an advanced stage when the pulmonary tumor has been invaded beyond the respiratory system. Therefore, chemotherapy is suitable for curing metastasized tumor. Baicalin (BL) is a flavonoid which has been studied in the treatment of several types of cancer including lung cancer. However, its low solubility in water and non-specificity impede its practical utilization. Hence, we have reported a stearic acid and pluronic F68 conjugated nanomicelles (PF68-SA) system to improve therapeutic efficacy of BL. Solvent evaporation method was used to prepare the BL-loaded PF68-SA nanomicelles (BLNM). The designed BLNM were characterized for the particle size, surface charge, critical micelle concentration, colloidal stability, morphology, and total drug content. BLNM formulation showed improved toxicity of BL against A549 human lung cancer cells in cytotoxicity assay. Further, apoptosis study also depicted BLNM-induced cell death in A549 cells. Therefore, the synthesized fatty acid-modified polymeric nanomicellar system could be useful in overcoming the stability and low therapeutic efficacy issues of hydrophobic anticancer drugs like BL and delivering them to the cancer cells.