A biocompatible cobaltporphyrin-based complex micelle constructed via supramolecular assembly for oxygen transfer

Self-Assembling Peptidic Bolaamphiphiles for Biomimetic Applications

Bolaamphiphile, which is a class of amphiphilic molecules, has a unique structure of two hydrophilic head groups at the ends of the hydrophobic center. Peptidic bolaamphiphiles that employ peptides or amino acids as their hydrophilic groups exhibit unique biochemical activities when they self-organize into supramolecular structures, which are not observed in a single molecule. The self-assembled peptidic bolaamphiphiles hold considerable promise for imitating proteins with biochemical activities, such as specific affinity toward heterogeneous substances, a catalytic activity similar to a metalloenzyme, physicochemical activity from harmonized amino acid segments, and the capability to encapsulate genes like a viral vector. These diverse activities give rise to large research interest in biomaterials engineering, along with the synthesis and characterization of the assembled structures. This review aims to address the recent progress in the applications of peptidic bolaamphiphile assemblies whose densely packed peptide motifs on their surface and their stacked hydrophobic centers exhibit unique protein-like activity and designer functionality, respectively.

Artificial Oxygen Carriers-Past, Present, and Future-a Review of the Most Innovative and Clinically Relevant Concepts

Blood transfusions are a daily practice in hospitals. Since these products are limited in availability and have various, harmful side effects, researchers have pursued the goal to develop artificial blood components for about 40 years. Development of oxygen therapeutics and stem cells are more recent goals. Medline (https://www.ncbi.nlm.nih.gov/pubmed/?holding=ideudelib), ClinicalTrials.gov (https://clinicaltrials.gov), EU Clinical Trials Register (https://www.clinicaltrialsregister.eu), and Australian New Zealand Clinical Trials Registry (http://www.anzctr.org.au) were searched up to July 2018 using search terms related to artificial blood products in order to identify new and ongoing research over the last 5 years. However, for products that are already well known and important to or relevant in gaining a better understanding of this field of research, the reader is punctually referred to some important articles published over 5 years ago. This review includes not only clinically relevant substances such as heme-oxygenating carriers, perfluorocarbon-based oxygen carriers, stem cells, and organ conservation, but also includes interesting preclinically advanced compounds depicting the pipeline of potential new products. In- depth insights into specific benefits and limitations of each substance, including the biochemical and physiologic background are included. "Fancy" ideas such as iron-based substances, O₂ microbubbles, cyclodextranes, or lugworms are also elucidated. To conclude, this systematic up-to-date review includes all actual achievements and ongoing clinical trials in the field of artificial blood products to pursue the dream of artificial oxygen carrier supply. Research is on the right track, but the task is demanding and challenging.

Mixed-Charged Zwitterionic Polymeric Micelles for Tumor Acidic Environment Responsive Intracellular Drug Delivery

A new class of mixed-charged zwitterionic copolymer poly(aminoethyl methacrylate)- co-poly(methacrylic acid)- co-poly( n-butyl methacrylate) (CPMA) was prepared as drug nanocarrier for efficient intracellular delivery of Doxorubicin (DOX). The mixed-charged CPMA copolymer could readily assemble to micelles in physiological environment (pH 7.4) with the size of 42.6 nm and zeta potential of -26 mV, which would lead to a prolonged circulation time and enhanced tumor penetration. However, the micelles formed large aggregates due to the protonation of carboxyl groups at extracellular tumor pH (pH 6.5). Meanwhile, the zeta potential of CPMA micelles increased from -26 mV to -6 mV when the solution pH was changed from pH 7.4 to pH 6.5. The increase of size and zeta potential at extracellular tumor pH could benefit the retention of micelles in tumor matrix and uptake by cancer cells. The DOX-loaded mixed-charged CPMA micelles could induce a higher internalization at pH 6.5 than 7.4 at varied time periods. Moreover, cytotoxicity assay demonstrated that the blank micelles showed excellent biocompatibility, but were highly cytotoxic toward KB cells after loading with DOX. Thus, the mixed-charged zwitterionic polymeric micelles might be a promising carrier for tumor acidic environment responsive drug delivery.

Bioinspired hierarchically hairy particles for robust superhydrophobic coatings via a droplet dynamic template method

Bioinspired hierarchically hairy particles are prepared by using initiator droplets as dynamic templates to achieve a robust superhydrophobic coating.

A hemoglobin-based oxygen carrier sensitized Cisplatin based chemotherapy in hepatocellular carcinoma

Background and Objective

Our previous study showed that liver graft injury not only promotes tumor recurrence, but also induces chemoresistance in recurrent HCC after liver transplantation. Recently, we found that the hemoglobin-based oxygen carrier“YQ23” significantly ameliorates hepatic IR injury and prevent tumor recurrence. Here, we intended to explore the novel therapeutic strategy using oxygen carrier “YQ23”to sensitize chemotherapy in HCC.

Methods

To investigate the role of YQ23 combined with Cisplatin, the proliferation of HCC cells was examined under combined treatment by MTT and colony formation. To explore the effect of YQ23 on sensitization of Cisplatin based chemotherapy, the orthotopic liver cancer model was established. To characterize the delivery of YQ23 in tumor tissue, the intravital imaging system was applied for longitudinal observation in ectopic liver cancer model. The distribution of YQ23 was examined by IVIS spectrum.

Results

YQ23 significantly suppressed the proliferation of HCC cells under Cisplatin treatment in a dose and time dependent manner. Moreover, YQ23 administration significantly sensitized Cisplatin based chemotherapy in orthotopic liver cancer model. Down-regulation of DHFR may be one of the reasons for YQ23 sensitizing Cisplatin based chemotherapy. Real-time intravital imaging showed that YQ23 accumulated in the tumor tissue and maintained as long as 3 days in ectopic liver cancer model. The IVIS spectrum examination showed that YQ23 distributed mainly at liver and bladder within the first 36 hours after administration in orthotopic liver cancer model.

Conclusion

YQ23 treatment may be a potential therapeutic strategy to sensitize chemotherapy in HCC.

Zinc porphyrin/fullerene/block copolymer micelle for enhanced electron transfer ability and stability

The complex micelle is constructed through an electrostatic self-assembly strategy as an efficient donor–acceptor system in water with electron transfer ability.

Hemin-micelles immobilized in alginate hydrogels as artificial enzymes with peroxidase-like activity and substrate selectivity

Hemin-micelles immobilized in hydrogels were designed, which function as efficient artificial enzymes with high catalytic activity and substrate selectivity.

Cooperative self-assembly of porphyrins with polymers possessing bioactive functions

This review covers recent research on design strategies for the cooperative self-assembly of porphyrins with polymers and its implementation as bioactive assembly.