Comprehensive Review on the Degradation Chemistry and Toxicity Studies of Functional Materials

Antimicrobial activity of metal-based nanoparticles: a mini-review

The resistance of pathogenic microorganisms to antibiotics is one of the main problems of world health. Of particular concern are multidrug-resistant (MDR) bacteria. Infections caused by these microorganisms affect the appearance of acute or chronic diseases. In this regard, modern technologies, such as nanomaterials (NMs), especially promising nanoparticles (NPs), can possess antimicrobial properties or improve the effectiveness and delivery of known antibiotics. Their diversity and characteristics, combined with surface functionalization, enable multivalent interactions with microbial biomolecules. This article presents an overview of the most current research on replacing antibiotics with NPs, including the prospects and risks involved.

Relationships between the Photodegradation Reaction Rate and Structural Properties of Polymer Systems

The development of reusable polymeric materials inspires an attempt to combine renewable biomass with upcycling to form a biorenewable closed system. It has been reported that 2,5-furandicarboxylic acid (FDCA) can be recovered for recycling when incorporated as monomers into photodegradable polymeric systems. Here, we develop a procedure to better understand the photodegradation reactions combining density functional theory (DFT) based time-dependent excited-state molecular dynamics (TDESMD) studies with machine learning-based quantitative structure-activity relationships (QSAR) methodology. This procedure allows for the unveiling of hidden structural features between active orbitals that affect the rate of photodegradation and is coined InfoTDESMD. Findings show that electrotopological features are influential factors affecting the rate of photodegradation in differing environments. Additionally, statistical validations and knowledge-based analysis of descriptors are conducted to further understand the structural features' influence on the rate of photodegradation of polymeric materials.

Bioconjugation Techniques for Enhancing Stability and Targeting Efficiency of Protein and Peptide Therapeutics

Bioconjugation techniques have emerged as powerful tools for enhancing the stability and targeting efficiency of protein and peptide therapeutics. This review provides a comprehensive analysis of the various bioconjugation strategies employed in the field. The introduction highlights the significance of bioconjugation techniques in addressing stability and targeting challenges associated with protein and peptide-based drugs. Chemical and enzymatic bioconjugation methods are discussed, along with crosslinking strategies for covalent attachment and site-specific conjugation approaches. The role of bioconjugation in improving stability profiles is explored, showcasing case studies that demonstrate successful stability enhancement. Furthermore, bioconjugation techniques for ligand attachment and targeting are presented, accompanied by examples of targeted protein and peptide therapeutics. The review also covers bioconjugation approaches for prolonging circulation and controlled release, focusing on strategies to extend half-life, reduce clearance, and design-controlled release systems. Analytical characterization techniques for bioconjugates, including the evaluation of conjugation efficiency, stability, and assessment of biological activity and targeting efficiency, are thoroughly examined. In vivo considerations and clinical applications of bioconjugated protein and peptide therapeutics, including pharmacokinetic and pharmacodynamic considerations, as well as preclinical and clinical developments, are discussed. Finally, the review concludes with an overview of future perspectives, emphasizing the potential for novel conjugation methods and advanced targeting strategies to further enhance the stability and targeting efficiency of protein and peptide therapeutics.

Electronic and photophysical properties of an atomically thin bowl-shaped beryllene encapsulated inside the cavity of [6]cycloparaphenylene (Ben@[6]CPP)

Exotic metallic nanostructures are being intensely pursued for a myriad of applications, with ultrathin membranes currently at the heart of several investigations. The objective of the present study was to systematically assess the atom-by-atom encapsulation of Be in the molecular nanoring of [6]cycloparaphenylene ([6]CPP). Further, the study aimed to scrutinize the structure, stability, and properties of the encapsulated Ben@[6]CPP systems. The outcomes clearly revealed that [6]CPP enabled the cooperative confinement of atomically thin bowl-shaped beryllene inside its circular cavity. The confinement of Be in [6]CPP generated topologically anisotropic surfaces with distinct interior and exterior charge distributions. The Ben@[6]CPP complexes could render a cationic or anionic nature to Be depending on its neighbouring environment. Thus, the systems may offer a promising opportunity for the synergistic co-adsorption of multiple reactants that are involved in multicomponent reactions. Energy decomposition analysis (EDA) elucidated that the bonding between Be and [6]CPP was partially ionic and covalent in character. The progressive encapsulation of Be atoms inside the cavity of [6]CPP led to a red-shift of the excitation wavelength to the visible region. The calculated optical absorption coefficient was higher than 104 L mol-1 cm-1, which shows promise for diverse optoelectronic applications.

Nanoscale Iron-Based Metal-Organic Frameworks: Incorporation of Functionalized Drugs and Degradation in Biological Media

Metal-organic frameworks (MOFs) attract growing interest in biomedical applications. Among thousands of MOF structures, the mesoporous iron(III) carboxylate MIL-100(Fe) (MIL stands for the Materials of Lavoisier Institute) is among the most studied MOF nanocarrier, owing to its high porosity, biodegradability, and lack of toxicity. Nanosized MIL-100(Fe) particles (nanoMOFs) readily coordinate with drugs leading to unprecedented payloads and controlled release. Here, we show how the functional groups of the challenging anticancer drug prednisolone influence their interactions with the nanoMOFs and their release in various media. Molecular modeling enabled predicting the strength of interactions between prednisolone-bearing or not phosphate or sulfate moieties (PP and PS, respectively) and the oxo-trimer of MIL-100(Fe) as well as understanding the pore filling of MIL-100(Fe). Noticeably, PP showed the strongest interactions (drug loading up to 30 wt %, encapsulation efficiency > 98%) and slowed down the nanoMOFs' degradation in simulated body fluid. This drug was shown to bind to the iron Lewis acid sites and was not displaced by other ions in the suspension media. On the contrary, PS was entrapped with lower efficiencies and was easily displaced by phosphates in the release media. Noticeably, the nanoMOFs maintained their size and faceted structures after drug loading and even after degradation in blood or serum after losing almost the totality of the constitutive trimesate ligands. Scanning electron microscopy with high annular dark field (STEM-HAADF) in conjunction with X-Ray energy-dispersive spectrometry (XEDS) was a powerful tool enabling the unraveling of the main elements to gain insights on the MOF structural evolution after drug loading and/or upon degradation.

Ring-Opening Polymerization of Trimethylene Carbonate with Phosphazene Organocatalyst

Aliphatic polycarbonate (APC) compounds are an important class of biodegradable materials with excellent biocompatibility, good biodegradability, and low toxicity, and the study of these compounds and their modification products aims to obtain biodegradable materials with better performance. In this context, the ring-opening polymerization (ROP) of trimethylene carbonate (TMC) from a low nucleophilic organic superbase of phosphazene (t-BuP₄) as a catalyst and benzyl alcohol (BnOH) as an initiator at room temperature was carefully studied to prepare poly(trimethylene carbonate) (PTMC) which is one of the most studied APC. ¹H NMR and SEC measurements clearly demonstrate the presence of a benzyloxy group at the α-terminus of the obtained PTMC homopolymers while investigation of the polymerization kinetics confirms the controlled/living nature of t-BuP₄-catalyzed ROP of TMC. On the basis of this, the block copolymerization of TMC and δ-valerolactone (VL)/ε-caprolactone (CL) was successfully carried out to give PTMC-b-PCL and PTMC-b-PVL copolymers. Furthermore, PTMC with terminal functionality was also prepared with the organocatalytic ROP of TMC through functional initiators. We believe that the present ROP system is a robust, highly efficient, and practical strategy for producing excellent biocompatible and biodegradable PTMC-based materials.