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Supramolecular polymers (SPs) are an emerging class of drug transporters employed to improve drug therapy. Through the rational design of self-assembling monomers, one can optimize the properties of the resulting supramolecular nanostructures, such as size, shape, surface chemistry, release, and, therefore, biological fates. This study highlights the design of isomeric SN38 prodrugs through the conjugation of hydrophilic oligo(ethylene glycol) (OEG) with hydroxyls at positions 10 and 20 on hydrophobic SN-38. Self-assembling prodrug (SAPD) isomers 10-OEG-SN38 and 20-OEG-SN38 can self-assemble into giant nanotubes and filamentous assemblies, respectively, via aromatic associations that dominate self-assembly. Our study reveales the influence of modification sites on the assembly behavior and ability of the SN38 SAPDs, as well as drug release and subsequent in vitro and in vivo antitumor effects. The SAPD modified at position 20 exhibits stronger π–π interactions among SN38 units, leading to more compact packing and enhanced assembly capability, whereas OEG at position 10 poses steric hindrance for aromatic associations. Importantly, owing to its higher chemical and supramolecular stability, 20-OEG-SN38 outperforms 10-OEG-SN38 and irinotecan, a clinically used prodrug of SN38, in a CT26 tumor model, demonstrating enhanced tumor growth inhibition and prolonged animal survival. This study presents a new strategy of using interactions among drug molecules as dominating features to create supramolecular assemblies. It also brings some insights into creating effective supramolecular drug assemblies via the engineering of self-assembling building blocks, which could contribute to the optimization of design principles for supramolecular drug delivery systems. [ABSTRACT FROM AUTHOR]

Poor prognosis is often expected after the treatment of intracerebral haemorrhage (ICH) when the approach lacks effective neuroprotective interventions. Minocycline (Mino) is a promising clinical neuroprotective candidate for acute ICH therapy that mainly inhibits activation of microglia/macrophages. However, to address iron neurotoxicity, ferroptosis, and oxidative stress‐induced multiple neuroinjury mechanisms, the neuroprotective effect of minocycline still urgently needs to be enhanced. To address this issue, procyanidins (PACs), typical natural polyphenols, is used to improve the neuroprotective effect of Mino by constructing PACs‐Mino nanoparticles (NPs) using 3‐aminophenylboronic acid as the crosslinker. The yielding NPs possessed improved antioxidant and iron‐removing capacities in vitro. More importantly, PACs‐Mino NPs exerted excellent therapeutic effects on ICH, showing improved neuroprotective activity and resulting in neurobehavioral recovery, in an in vitro cellular model and an in vivo ICH rat model. This study can provide a general strategy that uses natural polyphenols to boost the performance of drugs for ICH treatment, and the results may be further extended to other injuries of the central nervous system, such as brain injury and spinal cord injury. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have emerged as a promising class of zero-dimensional (0D) carbon nanomaterials due to their outstanding photoluminescence and electrical properties, along with their non-toxic, non-hazardous, and biocompatible advantages. These unique properties have sparked considerable interest in their applications in various fields. The utilization of biomass and plastic wastes as carbon sources to prepare CDs has become a significant area of research interest in recent years, driven by the increasingly strict environmental regulations and the growing volume of waste generated during production processes. In this context, a comprehensive and timely review of the fabrication, structures, properties, and applications of biomass and plastic wastes-derived CDs would significantly expand this field of research. Here, we present an overview of the fabrication methods of biomass and plastic wastes-derived CDs, employing either a top-down or bottom-up strategy. Furthermore, the most recent advances in the structures and properties of these CDs are highlighted and their utilization in polymer composites derived from biomass and plastic wastes are critically reviewed and summarized. Finally, the pending challenges and prospects for future research on polymer/biomass and plastic wastes-derived CDs composites for various applications are discussed. [ABSTRACT FROM AUTHOR]

In order to realize efficient expression of nucleoprotein (N) from rabies virus (RV) in the prokaryotic system, this paper refers to the RV N gene sequence published by GenBank (accession number 1489853) . Without changing the amino acid sequence of the RV N protein, the codon of the gene is optimized, and the N gene is chemically synthesized and cloned into the prokaryotic expression vector pET28a (+). The recombinant plasmid pET28a (+)/RV N is constructed and transformed into E. coli BL21 (DE3) competent cells for expression. The recombinant RV N protein is purified by His-tag nickel column. The purified RV N protein is then identified by SDS-PAGE and analyzed by Western blot. The results show that the recombinant plasmid is identified by double enzyme digestion, and a band appears at 1359 bp, which is completely consistent with the corresponding known gene sequence after sequence tests. When the recombinant bacteria are induced in an IPTG concentration of 0.1 mmol/L at 30 °C for 6 hours, the RV N protein expression is the highest. The RV N recombinant protein is obtained through the purification of the nickel column. The concentration of the recombinant RV N protein measured by BCA method is 1.783 mg/mL. An obvious western blot appears at 51 kD, which is consistent with the expected target band. It shows that RV N recombinant protein is successfully expressed in E. coli BL21 (DE3) competent cells, which lays a foundation for the subsequent rabies detection and the development of a new vaccine. [ABSTRACT FROM AUTHOR]