Boron nitride nanotube-CREKA peptide as an effective target system to metastatic breast cancer

Designing of a new transdermal antibiotic delivery polymeric membrane modified by functionalized SBA-15 mesoporous filler

A new drug delivery system using an asymmetric polyethersulfone (PES) membrane modified by SBA-15 and glutamine-modified SBA-15 (SBA-Q) was prepared in this study by the aim of azithromycin delivery enhancement in both in vitro and ex vivo experiments. The research focused on optimizing membrane performance by adjusting critical parameters including drug concentration, membrane thickness, modifier percentage, polymer percentage, and pore maker percentage. To characterize the fabricated membranes, various techniques were employed, including scanning electron microscopy, water contact angle, and tensile strength assessments. Following optimization, membrane composition of 17% PES, 2% polyvinylpyrrolidone, 1% SBA-15, and 0.5% SBA-Q emerged as the most effective. The optimized membranes demonstrated a substantial increase in drug release (906 mg/L) compared to the unmodified membrane (440 mg/L). The unique membrane structure, with a dense top layer facilitating sustained drug release and a porous sub-layer acting as a drug reservoir, contributed to this improvement. Biocompatibility assessments, antibacterial activity analysis, blood compatibility tests, and post-diffusion tissue integrity evaluations confirmed the promising biocompatibility of the optimized membranes. Moreover, long-term performance evaluations involving ten repeated usages underscored the reusability of the optimized membrane, highlighting its potential for sustained and reliable drug delivery applications.

Dendritic Self-assembled Structures from Therapeutic Charged Pentapeptides

CRE^NKA [Cys-Arg-(NMe)Glu-Lys-Ala, where (NMe)Glu refers to N-methyl-Glu], an anti-cancer pentapeptide that induces prostate tumor necrosis and significant reduction in tumor growth, was engineered to increase the resistance to endogenous proteases of its parent peptide, CREKA (Cys-Arg-Glu-Lys-Ala). Considering their high tendency to aggregate, the self-assembly of CRE^NKA and CREKA into well-defined and ordered structures has been examined as a function of peptide concentration and pH. Spectroscopic studies and atomistic molecular dynamics simulations reveal significant differences between the secondary structures of CREKA and CRE^NKA. Thus, the restrictions imposed by the (NMe)Glu residue reduce the conformational variability of CRE^NKA with respect to CREKA, which significantly affects the formation of well-defined and ordered self-assembly morphologies. Aggregates with poorly defined morphology are obtained from solutions with low and moderate CREKA concentrations at pH 4, whereas well-defined dendritic microstructures with fractal geometry are obtained from CRE^NKA solutions with similar peptide concentrations at pH 4 and 7. The formation of dendritic structures is proposed to follow a two-step mechanism: (1) pseudo-spherical particles are pre-nucleated through a diffusion-limited aggregation process, pre-defining the dendritic geometry, and (2) such pre-nucleated structures coalesce by incorporating conformationally restrained CRE^NKA molecules from the solution to their surfaces, forming a continuous dendritic structure. Instead, no regular assembly is obtained from solutions with high peptide concentrations, as their dynamics is dominated by strong repulsive peptide-peptide electrostatic interactions, and from solutions at pH 10, in which the total peptide charge is zero. Overall, results demonstrate that dendritic structures are only obtained when the molecular charge of CRE^NKA, which is controlled through the pH, favors kinetics over thermodynamics during the self-assembly process.

In Vitro and In Vivo Cytotoxicity of Boron Nitride Nanotubes: A Systematic Review

Boron nitride nanotubes (BNNTs) are an exciting class of nanomaterials due to their unique chemical and physical characteristics. In recent decades, BNNTs have gained huge attention in research and development for various applications, including as nano-fillers for composites, semiconductor devices, hydrogen storage, and as an emerging material in biomedical and tissue engineering applications. However, the toxicity of BNNTs is not clear, and the biocompatibility is not proven yet. In this review, the role of BNNTs in biocompatibility studies is assessed in terms of their characteristics: cell viability, proliferation, therapeutic outcomes, and genotoxicity, which are vital elements for their prospective use in biomedical applications. A systematic review was conducted utilising the databases Scopus and Web of Science (WOS) (2008-2022). Additional findings were discovered manually by snowballing the reference lists of appropriate reviews. Only English-language articles were included. Finally, the significant analysis and discussion of the chosen articles are presented.

Properties and applications of boron nitride nanotubes

Nanomaterials have received increasing attention due to their controllable physical and chemical properties and their improved performance over their bulk structures during the last years. Carbon nanostructures are one of the most widely searched materials for use in different applications ranging from electronic to biomedical because of their exceptional physical and chemical properties. However, BN nanostructures surpassed the attention of the carbon-based nanostructure because of their enhanced thermal and chemical stabilities in addition to structural similarity with the carbon nanomaterials. Among these nanostructures, one dimensional-BN nanostructures are on the verge of development as new materials to fulfill some necessities for different application areas based on their excellent and unique properties including their tunable surface and bandgap, electronic, optical, mechanical, thermal, and chemical stability. Synthesis of high-quality boron nitride nanotubes (BNNTs) in large quantities with novel techniques provided greater access, and increased their potential use in nanocomposites, biomedical fields, and nanodevices as well as hydrogen uptake applications. In this review, properties and applications of one-dimensional BN (1D) nanotubes, nanofibers, and nanorods in hydrogen uptake, biomedical field, and nanodevices are discussed in depth. Additionally, research on native and modified forms of BNNTs and also their composites with different materials to further improve electronic, optical, structural, mechanical, chemical, and biological properties are also reviewed. BNNTs find many applications in different areas, however, they still need to be further studied for improving the synthesis methods and finding new possible future applications.

Synthesis and evaluation of tumor-homing peptides for targeting prostate cancer

High toxicity caused by chemotherapeutic drugs and the acquisition of drug resistance by cancer cells are the major drawbacks in cancer therapy. A promising approach to overcome the posed barriers is conjugating tumor-homing peptides to drugs or nanocarriers. Such high-affinity peptides can specifically target surface markers overexpressed by cancer cells, ensuring a rapid and cancer-specific uptake of the drugs. Since prostate-specific membrane antigen (PSMA) is overexpressed by aggressive prostate cancer cells, targeting this surface protein with peptide conjugates can lead to the development of effective strategies against prostate cancer. In this study, we aimed to determine which PSMA-binding peptide among peptides 563, 562 and 9-mer, show the highest selectivity towards PSMA using 22Rv1 prostate cancer cells, a cell line with moderate PSMA levels. Tumor-homing peptides were synthesized by fluorenylmethoxycarbonyl-based solid-phase peptide synthesis (Fmoc-SPPS) strategy, and evaluated for their prostate cancer cell-specific targeting efficiencies by flow cytometry. Our results showed that the PSMA-binding capacity of peptide 563 was superior to those of 562, 9-mer, and 5-mer; therefore, can be utilized as a potent-targeting agent not only in the treatment of high PSMA positive but also moderate PSMA positive prostate cancer tumors.

Nanovesicle-Mediated Delivery Systems for CRISPR/Cas Genome Editing

Genome-editing technology has emerged as a potential tool for treating incurable diseases for which few therapeutic modalities are available. In particular, discovery of the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas system together with the design of single-guide RNAs (sgRNAs) has sparked medical applications of genome editing. Despite the great promise of the CRISPR/Cas system, its clinical application is limited, in large part, by the lack of adequate delivery technology. To overcome this limitation, researchers have investigated various systems, including viral and nonviral vectors, for delivery of CRISPR/Cas and sgRNA into cells. Among nonviral delivery systems that have been studied are nanovesicles based on lipids, polymers, peptides, and extracellular vesicles. These nanovesicles have been designed to increase the delivery of CRISPR/Cas and sgRNA through endosome escape or using various stimuli such as light, pH, and environmental features. This review covers the latest research trends in nonviral, nanovesicle-based delivery systems that are being applied to genome-editing technology and suggests directions for future progress.

Dual stimuli-responsive ursolic acid-embedded nanophytoliposome for targeted antitumor therapy

The hindrances in achieving clinically translatable anticancer platforms are being tackled through nanotechnology-based formulations. In this study, stimuli-responsive, phytoactive constituent-loaded nanophytoliposomes were fabricated for designing a specific antitumor platform. Ursolic acid (UA)-loaded nanophytoliposomes (UA-PLL-HA.P) enwrapped in a poly-L-lysine (PLL) coat and hyaluronic acid (HA) were nanosized; these nanophytoliposomes had spherical morphology, slightly negative charge, and an in-range polydispersity index (~0.25). Successful fabrication of the nanosystem was proven through several characterization methods and the pH- and enzyme-responsiveness of the nanosystem was assessed through a release study. The cellular internalization in CD44 receptor-expressing cell lines was amplified by enhanced permeation and retention as well as by active targeting. In vitro antitumor behavior was confirmed through in vitro cytotoxic and apoptotic activity of the nanosystem. Similarly, in vivo imaging showed exceptional biodistribution in the tumor in agreement with the in vitro findings. Moreover, the tumor inhibitory rate of UA-PLL-HA.P was significantly higher, and was ascribed to the targeting potential and stimuli-responsiveness. In summary, UA-PLL-HA.P exhibited pronounced anticancer effect and could open a number of possibilities for discovering novel phytoconstituent-incorporated nanoformulations.

Biomimetic polymeric nanoparticle-based photodynamic immunotherapy and protection against tumor rechallenge

In this study, we sought to design a bionanomaterial that could exert anticancer effects against primary tumors and protect against rechallenged tumorsviaphotodynamic immunotherapy.