Intrinsic Cytotoxicity Research Articles

Transition metal ions doped InP/ZnS quantum dots: toward the application of two-photon probes and type-I photosensitizers

Semiconductor colloidal quantum dots (QDs) are technologically important for multiphoton bioimaging and photodynamic therapy applications. However, most semiconductor QDs have intrinsic cytotoxicity and small Stokes shifts, which hinder their applications in diagnosis and treatment. In this work, a series of transition metal ions doped InP/ZnS QDs, including Cu: InP/ZnS and Mn: InP/ZnS QDs, are synthesized, and their optical properties are characterized. Interestingly, these doped InP/ZnS QDs possess strong two-photon absorption cross sections at 700 nm (100 fs, 80 MHz), up to ∼1.5 × 104 GM for Cu: InP/ZnS QDs (0.5% Cu) and ∼8.8 × 103 GM for Mn: InP/ZnS QDs (40% Mn). Importantly, both undoped and doped InP/ZnS QDs can generate electron-hole pairs to produce •OH and O2•− under 800 nm photoexcitation, which can be used as two-photon excited type-I photosensitizers. These findings constitute a comprehensive understanding of the transitional metal ions doped InP/ZnS QDs as the two-photon fluorescence probes and type-I photosensitizers.

Significant Advancements and Evolutions in Chimeric Antigen Receptor Design.

Recent times have witnessed remarkable progress in cancer immunotherapy, drastically changing the cancer treatment landscape. Among the various immunotherapeutic approaches, adoptive cell therapy (ACT), particularly chimeric antigen receptor (CAR) T cell therapy, has emerged as a promising strategy to tackle cancer. CAR-T cells are genetically engineered T cells with synthetic receptors capable of recognising and targeting tumour-specific or tumour-associated antigens. By leveraging the intrinsic cytotoxicity of T cells and enhancing their tumour-targeting specificity, CAR-T cell therapy holds immense potential in achieving long-term remission for cancer patients. However, challenges such as antigen escape and cytokine release syndrome underscore the need for the continued optimisation and refinement of CAR-T cell therapy. Here, we report on the challenges of CAR-T cell therapies and on the efforts focused on innovative CAR design, on diverse therapeutic strategies, and on future directions for this emerging and fast-growing field. The review highlights the significant advances and changes in CAR-T cell therapy, focusing on the design and function of CAR constructs, systematically categorising the different CARs based on their structures and concepts to guide researchers interested in ACT through an ever-changing and complex scenario. UNIVERSAL CARs, engineered to recognise multiple tumour antigens simultaneously, DUAL CARs, and SUPRA CARs are some of the most advanced instances. Non-molecular variant categories including CARs capable of secreting enzymes, such as catalase to reduce oxidative stress in situ, and heparanase to promote infiltration by degrading the extracellular matrix, are also explained. Additionally, we report on CARs influenced or activated by external stimuli like light, heat, oxygen, or nanomaterials. Those strategies and improved CAR constructs in combination with further genetic engineering through CRISPR/Cas9- and TALEN-based approaches for genome editing will pave the way for successful clinical applications that today are just starting to scratch the surface. The frontier lies in bringing those approaches into clinical assessment, aiming for more regulated, safer, and effective CAR-T therapies for cancer patients.

Apigenin: Molecular Mechanisms and Therapeutic Potential against Cancer Spreading.

Due to its propensity to metastasize, cancer remains one of the leading causes of death worldwide. Thanks in part to their intrinsic low cytotoxicity, the effects of the flavonoid family in the prevention and treatment of various human cancers, both in vitro and in vivo, have received increasing attention in recent years. It is well documented that Apigenin (4',5,7-trihydroxyflavone), among other flavonoids, is able to modulate key signaling molecules involved in the initiation of cancer cell proliferation, invasion, and metastasis, including JAK/STAT, PI3K/Akt/mTOR, MAPK/ERK, NF-κB, and Wnt/β-catenin pathways, as well as the oncogenic non-coding RNA network. Based on these premises, the aim of this review is to emphasize some of the key events through which Apigenin suppresses cancer proliferation, focusing specifically on its ability to target key molecular pathways involved in angiogenesis, epithelial-to-mesenchymal transition (EMT), maintenance of cancer stem cells (CSCs), cell cycle arrest, and cancer cell death.

VP5 protein of oncolytic herpes simplex virus type 2 induces apoptosis in A549 cells through TP53I3 protein

Oncolytic virotherapy stands out as a burgeoning and promising therapeutic paradigm, harnessing the intrinsic cytotoxicity of oncolytic viruses for selective replication and dissemination within tumors. The primary mode of action revolves around the direct eradication of tumor cells. In our previous investigations, we formulated an oncolytic herpes simplex virus type 2 (OH2) and substantiated its anti-tumor efficacy both in vivo and in vitro. Subsequently, we embarked on a phase I/II clinical trial in China (NMPA, 2018L02743) and the USA (FDA, IND 27137) to assess OH2's safety, biodistribution, and anti-tumor activity as a standalone agent in patients with advanced solid tumors. In this investigation, our primary focus was to comprehend the influence of the major capsid protein VP5 of OH2 on its efficacy as an antitumor agent. Our findings underscore that the VP5 protein significantly amplifies OH2's oncolytic impact on A549 cells. Additionally, we observed that VP5 actively promotes the induction of apoptosis in A549 cells, both in vivo and in vitro. Through comprehensive transcriptional sequencing, we further authenticated that the VP5 protein triggers apoptosis-related signaling pathways and Gene Ontology (GO) terms in A549 cells. Moreover, we scrutinized differentially expressed genes in the p53-dependent apoptosis pathway and conducted meticulous in vitro validation of these genes. Subsequently, we delved deeper into unraveling the functional significance of the TP53I3 gene and conclusively affirmed that the VP5 protein induces apoptosis in A549 cells through the TP53I3 gene. These revelations illuminate the underlying mechanisms of OH2's antitumor activity and underscore the pivotal role played by the VP5 protein. The outcomes of our study harbor promising implications for the formulation of effective oncolytic virotherapy strategies in cancer treatment.

Synthesis and evaluation of tryptanthrin derivatives as promising anticancer agents: In vitro, in silico, and SAR insights

In this study, with the aim of identifying new anticancer agents, we synthesized a series of tryptanthrin derivatives. All the synthesized compounds were investigated for their anticancer potential in-vitro, using an MTT-based assay against a panel of three different cancer cell lines (A-549, MCF-7, and MDA-MB-231). Amongst the synthesized derivatives, compound 3 showed excellent anticancer activity, with GI50 values of 5.03 ± 0.77 µM, 3.76 ± 0.55 µM, and 4.20 ± 0.50 µM against A-549, MDA-MB-231 and MCF-7 cells, respectively. Furthermore, these molecules did not show any cytotoxic effect against normal mouse embryonic fibroblast (NIH/3T3) cell lines suggesting no intrinsic cytotoxicity. In this study, ADME and toxicity profiles of the synthesized compounds were also predicted using in silico techniques. According to the findings, all of the synthesized derivatives are nontoxic and non-carcinogenic in the biological system and showed good ADME properties. Finally, potent compounds were subjected to in silico molecular docking and simulation studies were carried out against maternal embryonic leucine zipper kinase (MELK) to uncover potential protein-ligand interactions and affinity at the binding site. This study will help in the future development of novel anticancer agents.

Synthesis of Optically Pure Cyclometalated Iridium(III) Complex‐Peptide Hybrids and Their Anticancer Activity.

We report on the synthesis of optically pure cyclometalated iridium(III) complex‐peptide hybrids as amphiphilic peptide conjugates (IPH‐ACs) from Δ‐ and Λ‐Ir(tpyCO2H)3 (tpy: 2‐(4’‐tolyl)pyridine) by optical resolution via diastereomeric intermediates conjugated with the chiral alcohol, (1R,2R)‐2‐aminocyclohexanol ((R,R)‐11). Spectroscopic spectra of the optically pure IPH‐ACs that were prepared from Δ‐ and Λ‐Ir(tpyCO2H)3 are reported. It was found that both optically pure IPH‐ACs induce paraptotic cell death in Jurkat cells and the EC50 values were evaluated by MTT assays. We also performed TEM analyses of Jurkat cells treated with Λ‐13 to observe morphological changes that occurred, and cytoplasmic vacuolization, a characteristic feature of paraptosis, was observed. The intracellular uptake of IPH‐ACs by the cells measured by ICP‐MS (inductively coupled plasma‐mass spectrometry) was higher for the Λ‐forms and the EC50 values of the Λ‐forms were slightly lower than those of the Δ‐IPH‐ACs. The intrinsic cytotoxicity of the IPH‐ACs, taking into account the fact that the intracellular uptake and the intrinsic cytotoxicity is almost equal for the Δ‐ and Λ‐forms, suggests that the difference in cytotoxicity against Jurkat cells is due to the selectivity in the intracellular uptake of each stereoisomer.

Cardiotoxicity and ROS Protection Assessment of three Structure-Related N-Acylhydrazones with Potential for the Treatment of Neurodegenerative Diseases.

The senescence process is associated with accumulated oxidative damage and increased metal concentration in the heart and brain. Besides, abnormal metal-protein interactions have also been linked with the development of several conditions, including Alzheimer's and Parkinson's diseases. Over the years we have described a series of structure-related compounds with different activities towards models of such diseases. In this work, we evaluated the potential of three N-acylhydrazones (INHHQ: 8-hydroxyquinoline-2-carboxaldehyde isonicotinoyl hydrazone, HPCIH: pyridine-2-carboxaldehyde isonicotinoyl hydrazone and X1INH: 1-methyl-1H-imidazole-2-carboxaldehyde isonicotinoyl hydrazone) to prevent oxidative stress in cellular models, with the dual intent of being active on this pathway and also to confirm their lack of cardiotoxicity as an important step in the drug development process, especially considering that the target population often presents cardiovascular comorbidity. The 8-hydroxyquinoline-contaning compound, INHHQ, exhibits a significant cardioprotective effect against hydrogen peroxide and a robust antioxidant activity. However, this compound is the most toxic to the studied cell models and seems to induce oxidative damage on its own. Interestingly, although not possessing a phenol group in its structure, the new-generation 1-methylimidazole derivative X1INH showed a cardioprotective tendency towards H9c2 cells, demonstrating the importance of attaining a compromise between activity and intrinsic cytotoxicity when developing a drug candidate.

Synthesis and evaluation of WK-X-34 derivatives as P-glycoprotein (P-gp/ABCB1) inhibitors for reversing multidrug resistance.

The emergence of multidrug resistance (MDR) in malignant tumors is one of the leading threats encountered currently by many chemotherapeutic agents. A proposed strategy to overcome MDR is to disable the efflux function of P-glycoprotein (P-gp/ABCB1), a critical member of the ABC transporter family that significantly increases the efflux of various anticancer drugs from tumor cells. In this study, structural modification of a third-generation P-gp inhibitor WK-X-34 based on bioisosteric and fragment-growing strategies led to the discovery of the adamantane derivative PID-9, which exhibited the best MDR reversal activity (IC50 = 0.1338 μM, RF = 78.6) in this series, exceeding those of the reported P-gp inhibitors verapamil and WK-X-34. In addition, compared with WK-X-34, PID-9 showed decreased toxicity to cells. Furthermore, the mechanism studies revealed that the reversal activity of adamantane derivatives PID-5, PID-7, and PID-9 stemmed from the inhibition of P-gp efflux. These results indicated that compound PID-9 is the most effective P-gp inhibitor among them with low toxicity and high MDR reversal activity, which provided a fundamental structural reference for further discovery of novel, effective, and non-toxic P-gp inhibitors.

EDOT-pyrrole copolymer conductive nanoparticles and electrodes enhance galvanotaxis in Paramecium tetraurelia; a simple biological model for explorative experiments in therapeutic electrical stimulation

The galvanotaxis response of Paramecium tetraurelia was explored as a preliminary model for in vitro electrostimulation of other eukaryotic cells. Interestingly, electrodes coated with 3,4-ethylenedioxythiophene (EDOT) – pyrrole (Py) copolymer induced galvanotaxis in a similar manner and with even greater efficiency than conventional electrodes. Furthermore, in the absence of agar bridges, there was no release of toxic species into the cell medium or any deleterious effects on cell viability after several cycles of electrostimulation for 1 min. The intrinsic cytotoxicity of the copolymer was also investigated in Paramecium tetraurelia and mammalian cell lines. The copolymer did not show any toxic effects at concentrations below 1 mg/ml. Finally, it was discovered that galvanotaxis can be increased by up to 150 % concerning the control (with electrostimulation of 3V for 60s) in Paramecium cells treated with 10 μg/mL copolymer particles for 1 h and that showed endocytosis. Galvanotaxis is voltage-dependent, as it only increases by 100 % at 1.5 V, suggesting a sensitive physiological level effect on the Ca2+ currents and voltage-dependent Ca2+ channels of the cilia.

Inhibition of multidrug-resistant MCF-7 breast cancer cells with combinations of clinical drugs and resin glycosides from Operculina hamiltonii

The jalap roots, Operculina hamiltonii D.F. Austin & Staples (Convolvulaceae), are extensively commercialized as a depurative and laxative remedy in traditional medicine of the north and northeast regions of Brazil. The purification by recycling HPLC and structure elucidation of three new acyl sugars or resin glycosides are described here from a commercial product made of powdered roots. Three macrocyclic structures of a tetrasaccharide of (11S)-hydroxyhexadecanoic acid, operculinic acid C (1), the undescribed hamiltonins II and III (3 and 4), in addition to the known batatinoside III (5), presented a diastereoisomeric relationship as one residue of n-dodecanoic acid esterified the oligosaccharide core on a different position in each compound. Furthermore, hamiltonin IV (6) was characterized as an ester-type homodimer of acylated operculinic acid C with the same substitution pattern identified in hamiltonins II (3) and III (4) for each of the dimer subunits. All the isolated resin glycosides did not display any intrinsic cytotoxicity (IC50 > 25 μM). However, a combination of the individual isolated compounds 3–6 (1–50 μM) demonstrated an enhancement of cytotoxic effects with sublethal doses of vinblastine and podophyllotoxin (0.003 μM) in multidrug-resistant breast carcinoma epithelial cells (MCF-7/Vin).

β-Cyclodextrin Nanophotosensitizers for Redox-Sensitive Delivery of Chlorin e6.

The aim of this study is to prepare redox-sensitive nanophotosensitizers for the targeted delivery of chlorin e6 (Ce6) against cervical cancer. For this purpose, Ce6 was conjugated with β-cyclodextrin (bCD) via a disulfide bond, creating nanophotosensitizers that were fabricated for the redox-sensitive delivery of Ce6 against cancer cells. bCD was treated with succinic anhydride to synthesize succinylated bCD (bCDsu). After that, cystamine was attached to the carboxylic end of bCDsu (bCDsu-ss), and the amine end group of bCDsu-ss was conjugated with Ce6 (bCDsu-ss-Ce6). The chemical composition of bCDsu-ss-Ce6 was confirmed with 1H and 13C NMR spectra. bCDsu-ss-Ce6 nanophotosensitizers were fabricated by a dialysis procedure. They formed small particles with an average particle size of 152.0 ± 23.2 nm. The Ce6 release rate from the bCDsu-ss-Ce6 nanophotosensitizers was accelerated by the addition of glutathione (GSH), indicating that the bCDsu-ss-Ce6 nanophotosensitizers have a redox-sensitive photosensitizer delivery capacity. The bCDsu-ss-Ce6 nanophotosensitizers have a low intrinsic cytotoxicity against CCD986Sk human skin fibroblast cells as well as Ce6 alone. However, the bCDsu-ss-Ce6 nanophotosensitizers showed an improved Ce6 uptake ratio, higher reactive oxygen species (ROS) production, and phototoxicity compared to those of Ce6 alone. GSH addition resulted in a higher Ce6 uptake ratio, ROS generation, and phototoxicity than Ce6 alone, indicating that the bCDsu-ss-Ce6 nanophotosensitizers have a redox-sensitive biological activity in vitro against HeLa human cervical cancer cells. In a tumor xenograft model using HeLa cells, the bCDsu-ss-Ce6 nanophotosensitizers efficiently accumulated in the tumor rather than in normal organs. In other words, the fluorescence intensity in tumor tissues was significantly higher than that of other organs, while Ce6 alone did not specifically target tumor tissue. These results indicated a higher anticancer activity of bCDsu-ss-Ce6 nanophotosensitizers, as demonstrated by their efficient inhibition of the growth of tumors in an in vivo animal tumor xenograft study.

Apparent Cytotoxicity and Intrinsic Cytotoxicity of Lipid Nanomaterials Contained in a COVID-19 mRNA Vaccine

The medicinal preparation called Comirnaty by Pfizer-BioNTech is an aqueous dispersion of lipid nanomaterials, intended to constitute, after thawing and dilution, the finished product for intramuscular injection. In the present study, we examine some evident chemical-physical criticalities of the preparation, particularly regarding the apparent and the intrinsic pKa (acid dissociation constant) of its main excipient, the ionizable cationic lipid ALC-0315. The very high value of its intrinsic pKa causes, after internalization and endosomal escape of LNPs, a sudden increase of its cationic charge concentration and consequently the formation of pro-inflammatory cytokines and ROS (reactive oxygen species), that can disrupt the mitochondrial membrane and release its content, cause RNA mistranslation, polymerization of proteins and DNA, DNA mutations, destruction of the nuclear membrane and consequent release of its content. Additionally, the apparently low pKa value (6.09) of ALC-0315 associated with other lipids in the LNP, is not suitable for intramuscular application. Its value is too low to enable a proper transfection of host cells, despite what is stated by EMA (European Medicines Agency) in its Assessment report dated 19 February 2021, in flagrant contradiction with the same bibliographic source therein cited. Furthermore, the exceptional penetrability, mobility, chemical reactivity and systemic accumulation of uncontrollable cationic lipid nanoparticles, with high cytotoxicity levels, shed in unpredictable biological locations, even far from the site of inoculation, are all factors that can lead to an unprecedented medical disaster. Meanwhile, further immediate studies and verifications are recommended, taking into consideration, in accordance with the precautionary principle, the immediate suspension of vaccinations with the COVID-19 mRNA- LNP-based vaccines.

Chlorhexidine-Silver Nanoparticle Conjugation Leading to Antimicrobial Synergism but Enhanced Cytotoxicity.

This study explored the potential synergism within chlorhexidine-silver nanoparticle conjugates against Influenza type A, Staphylococcus aureus, Escherichia coli, and Candida albicans. Silver nanoparticles (SN) were obtained by the reduction of silver ions with green tea total phenolic extract and conjugated with chlorhexidine (Cx). The particles were characterized by UV-Vis and FTIR spectroscopies, dynamic light scattering, X-ray diffraction, and transmission electron microscopy. A stable negatively charged nano-silver colloid (ζ = -50.01) was obtained with an average hydrodynamic diameter of 92.34 nm. In the presence of chlorhexidine, the spectral data and the shift of the zeta potential to positive values (ζ = +44.59) revealed the successful sorption of the drug onto the silver surface. The conjugates (SN-Cx) demonstrated potentiation in their effects against S. aureus and C. albicans and synergism against E. coli with minimal inhibitory concentrations of SN at 5.5 µg/mL + Cx 8.8 µg/mL. The SN showed excellent virucidal properties, increasing with time, and demonstrated low toxicity. However, the coupling of the cationic chlorhexidine with nano-silver did not reduce its intrinsic cytotoxicity on various cell lines (MDCK, BJ, and A549). The newly synthesized antimicrobial agent exhibited an extended and promising therapeutic spectrum and needs to be further evaluated regarding the designated route of administration in three-dimensional cell models (e.g., nasal, bronchial, dermal, ocular, etc.).

An optimized cultivation method for future in vivo application of γδ T cells.

γδ T cells, with their properties of both the innate and acquired immune systems, are suitable candidates for cellular immunotherapy in cancer. Because of their non-major histocompatibility complex (MHC) binding T cell receptor, allogenic transfer is feasible without relevant graft versus host reactions. In recent years, much experience has been gained with ex vivo expansion and stimulation of γδ T cells using bisphosphonates and Interleukin 2. Unfortunately, many current stimulation protocols are based on the use of xenogenic materials and other potentially hazardous supplements, which conflicts with basic principles of Good Manufacturing Practice (GMP). Adherence to the concept and current guidelines of GMP is state of the art for production of Advanced Therapy Medicinal Products (ATMP) like cell therapeutics and a necessity for clinical use under a regulatory perspective. In this study, we developed a new stimulation protocol that induces a marked increase of γδ T cell counts and allows for an easier transition from research to clinical applications with minimized regulatory workload. It reliably leads to a cell product with a purity of more than 90% γδ T cells and improved in vitro anti-tumor activity compared to our previous standard procedure. Furthermore, by investigating correlations between properties of unstimulated γδ T cells and proliferation rate as well as degranulation ability of stimulated γδ T cells, we can draw conclusions about suitable donors. Finally, we examined if expansion can be improved by pulsing zoledronate and/or using Interleukin 15 with or without Interleukin 2. Significant improvements can be achieved with respect to intrinsic and antibody-dependent cell-mediated cytotoxicity. Our results demonstrate that the stimulation protocol presented here leads to an improved γδ T cell product for future clinical applications.

Hyaluronic acid‐folic acid‐modified Fe3O4 magnetic nanocarriers for targeted delivery of piperine: Formation, characterization, and biological study

Biocompatibility targeted magnetic nanocarriers are a promising alternative to conventional chemotherapy. Herein, Fe3O4 magnetic nanoparticles (MNPs) functionalized hyaluronic acid (HA)‐folic acid (FA) was synthesized and piperine (PIP) loaded into MNPs. In vitro release analyses, antioxidant activity, hemolysis assay, and intrinsic cytotoxicity of MNPs were determined. The results revealed that the synthesized MNPs released higher amount of piperine in acidic ambience in comparison with neutral ambience. PIP‐loaded prepared MNPs exhibited higher antioxidant activity in comparison with the carrier. On the other hand, prepared Fe3O4 MNPs is hemocompatible. Also, the synthesized MNPs demonstrated the considerable antiproliferative effects in MCF‐7 cancer cells compared with fibroblast cells. The results suggest that Fe3O4‐NH‐HA‐FA MNPs as novel targeted delivery system can enhance the therapeutic effect of piperine.

Paclitaxel-Loaded Lipid-Coated Magnetic Nanoparticles for Dual Chemo-Magnetic Hyperthermia Therapy of Melanoma.

Melanoma is the most aggressive and metastasis-prone form of skin cancer. Conventional therapies include chemotherapeutic agents, either as small molecules or carried by FDA-approved nanostructures. However, systemic toxicity and side effects still remain as major drawbacks. With the advancement of nanomedicine, new delivery strategies emerge at a regular pace, aiming to overcome these challenges. Stimulus-responsive drug delivery systems might considerably reduce systemic toxicity and side-effects by limiting drug release to the affected area. Herein, we report the development of paclitaxel-loaded lipid-coated manganese ferrite magnetic nanoparticles (PTX-LMNP) as magnetosomes synthetic analogs, envisaging the combined chemo-magnetic hyperthermia treatment of melanoma. PTX-LMNP physicochemical properties were verified, including their shape, size, crystallinity, FTIR spectrum, magnetization profile, and temperature profile under magnetic hyperthermia (MHT). Their diffusion in porcine ear skin (a model for human skin) was investigated after intradermal administration via fluorescence microscopy. Cumulative PTX release kinetics under different temperatures, either preceded or not by MHT, were assessed. Intrinsic cytotoxicity against B16F10 cells was determined via neutral red uptake assay after 48 h of incubation (long-term assay), as well as B16F10 cells viability after 1 h of incubation (short-term assay), followed by MHT. PTX-LMNP-mediated MHT triggers PTX release, allowing its thermal-modulated local delivery to diseased sites, within short timeframes. Moreover, half-maximal PTX inhibitory concentration (IC50) could be significantly reduced relatively to free PTX (142,500×) and Taxol® (340×). Therefore, the dual chemo-MHT therapy mediated by intratumorally injected PTX-LMNP stands out as a promising alternative to efficiently deliver PTX to melanoma cells, consequently reducing systemic side effects commonly associated with conventional chemotherapies.

Design and evaluation of dibenzoazepine-tetrahydroisoquinoline hybrids as potential P-glycoprotein inhibitors against multidrug resistant K562/A02 cells

Multidrug resistance (MDR) caused by P-glycoprotein (P-gp) is a main barrier to the success of cancer chemotherapies. In this study, fourteen novel dibenzoazepine-tetrahydroisoquinoline hybrids were prepared as potential P-gp inhibitors to surmount MDR caused by P-gp. Amongst them, 8a displayed the most potent inhibition effect on P-gp, thus effectively reversing P-gp-mediated drug resistance with a reversal fold (RF) value of 93.17 in K562/A02 cells. Excitingly, the EC50 value of 8a on MDR reversing effect was 48.74 nM, which was nearly two thousand-fold lower than its IC50 value (95.94 μM) for intrinsic cytotoxicity on K562/A02 cells. Further investigation showed that 8a exerted the MDR reversal effect through impairing P-gp function rather than affecting its expression. Molecular docking and CETSA results illustrated that 8a possessed a relatively high affinity for P-gp, thus effectively improving the stability of P-gp. Furthermore, 8a exhibited a much poorer inhibitory effect on CYP3A4 activity than CYP3A4 inhibitor ketoconazole, thus might not cause unfavorable drug-drug interactions. These data together suggested that 8a may be a promising lead to design P-gp inhibitors, and warranted further investigation on overcoming P-gp-mediated MDR.

Highly durable photocatalytic titanium suboxide–polymer nanocomposite films with visible light-triggered antibiofilm activity

Bacterial biofilms on medical devices may result in infections with significant societal burden. One drug-free strategy against biofilms is photocatalysis, in which a semiconducting coating is applied on the medical device and irradiated with light to generate reactive oxygen species providing an on-demand disinfection approach. However, most photocatalytic materials are active in the harmful UV range rendering them unsuitable for biomedical applications. Furthermore, the main manufacturing bottleneck today for antibiofilm coatings is their poor durability. To address these challenges, here we produced silver/titanium-suboxide nanoparticles that are photocatalytically active in the visible-light range. Moreover, we directly deposited the nanoparticles as porous coatings on substrates in situ during their aerosol synthesis. To enhance their durability, we infused the fabricated porous coatings with a polymer solution barely covering the photocatalytic particle film, resulting in the formation of polymer nanocomposite coatings. The optimized polymer nanocomposite films exhibit several cycles of triggered, on-demand biofilm eradication activity under short visible light illumination of 15–90 min with no significant intrinsic cytotoxicity to mammalian cells. The developed films can be considered as a suitable coating material for medical devices, such as catheters, ventilators, wound meshes, and others, that may require repeated disinfection during use.

Synthesis of magnetic bio-nanocomposites for drug release and adsorption applications

Aims: Synthesis of nanocarrier Fe3O4/silica-starch/PNVCL for drug delivery and Fe3O4/GO-starch for antibiotic removal applicationsBackground: In the first part, the new magnetic nanocomposite including Fe3O4 nanoparticles coated with silica, anchored starch nanoparticles, and poly(N-vinylcaprolactam) and then, loaded by acetazolamide. In the second part, magnetic starch nanocomposites were synthesized and modified with graphene oxide.Methods: The drug loading, release and intrinsic cytotoxicity were measured. Also, the potential of Fe3O4/GO-starch as an adsorbent to remove cephalexin antibiotics from aqueous solutions was evaluated.Result: In the first part, the maximum drug adsorption was occurred at pH = 7 on the nanocarrier and the Langmuir model looks more suitable for describing the adsorption process at room temperature. The second study showed that the maximum adsorption of cephalexin at pH 4 for magnetic nanocomposites in good agreement with the Freundlich model and the adsorption kinetics followed the quasi-quadratic model.Conclusion: It seems that the prepared nanocarrier Fe3O4/silica-starch/PNVCL can be utilized as a promising candidate for drug delivery. Also, magnetic nanocomposites of Fe3O4/GO-starch can be used as suitable and inexpensive adsorbents in cephalexin removal.

Bio-synthesis of a functionalized whey proteins theranostic nanoprobe with cancer-specific cytotoxicity and as a live/dead cell imaging probe

In the recent decades, bio-synthesized gold nanoparticles (AuNPs) are the most prevalent nanomaterials that widely used in different biomedical applications due to their low toxicity and good stability. Here a facile, cost-effective and eco-friendly approach has been developed for the fabrication of anisotropic AuNPs using the whey proteins (Wh@AuNPs) by mixing an aqueous tetrachloroauric acid with whey for the first time. Interestingly, it was found that the fluorescent signal of Wh@AuNPs could be changed by adding trypan blue (TB) dye to the living cells, so it can be used to identify live and dead cells using fluorescence microscopy. The results showed that the wh@AuNPs have intrinsic specific cytotoxicity against cancer cells, which introduce it as a suitable theranostic nanoparticle.