PVA-Based Nanofibers Containing Chitosan Modified with Graphene Oxide and Carbon Quantum Dot-Doped TiO2 Enhance Wound Healing in a Rat Model

Development and physiochemical assessment of graphene-bioactive glass-P(3HB-co-4HB) composite scaffold as prospect biomaterial for wound healing

The clinical management of wounds presents a considerable challenge because dressing selection must prioritise the provision of appropriate barrier and the healing properties, consider patient's compliance factors such as comfort, functionality and practicality. This study primarily aimed to develop a composite scaffold patch for potential application in wound healing. Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] is a biopolymer that originated from bacteria. It is well-recognised owing to its distinctive mechanical and physical characteristics suitable for biomedical applications. Graphene (G) and bioactive glass (BG) are biocompatible towards humans, and enhanced properties are achievable by adding biopolymer. In this study, composite scaffolds were developed by combining P(3HB-co-4HB) at a distinct proportion of 4HB monomer reinforced with G (3.0 wt.%) and BG (2.5 wt.%) by using solvent casting, resulting in two types of composite scaffolds: P(3HB-co-25%4HB)/G/BG and P(3HB-co-37%4HB)/G/BG. A successful composite scaffold as a unified structure was achieved based on chemical assessments of organic and inorganic elements within the composites. The pure polymer displayed a smooth surface, and the BG and G addition into the composite scaffolds increased surface roughness, forming irregular pores and protuberances. The wettability and hydrophilicity of the composites significantly improved up to 40% in terms of water uptake. An increment in crystallisation temperature diminished the flexibility of the composite's scaffolds. Evaluation of Presto Blue biocompatibility demonstrated nontoxic behaviour with a dosage of less than 25.00 mg ml-1of composite scaffold-conditioned media. The L929 fibroblast cells displayed excellent adhesion to both types of composite scaffolds, as evidenced by the increased percentage of cell viability observed throughout 14 d of exposure. These findings demonstrate the importance of optimising each component within the composite scaffolds and their interrelation, paving the way for excellent material properties and enhancing the potential for wound healing applications.

Nitric oxide-releasing thiolated starch nanoparticles embedded in gelatin sponges for wound dressing applications

This study introduces a novel wound dressing by combining nitric oxide-releasing thiolated starch nanoparticles (NO-TS NPs) with gelatin. First, starch was thiolated (TS), and then its nanoparticles were prepared (TS NPs). Subsequently, NPs were covalently bonded to sodium nitrite to obtain NO-releasing TS NPs (NO-TS-NPs) that were incorporated into gelatin sponges at various concentrations. The resulting spherical TS NPs had a mean size of 85.42 ± 5.23 nm, which rose to 100.73 ± 7.41 nm after bonding with sodium nitrite. FTIR spectroscopy confirmed S-nitrosation on the NO-TS NPs' surface, and morphology analysis showed well-interconnected pores in all sponges. With higher NO-TS NPs content, pore size, porosity, and water uptake increased, while compressive modulus and strength decreased. Composites exhibited antibacterial activity, particularly against E. coli, with enhanced efficacy at higher NPs' concentrations. In vitro release studies demonstrated Fickian diffusion, with faster NO release in sponges containing more NPs. The released NO amounts were non-toxic to fibroblasts, but samples with fewer NO-TS NPs exhibited superior cellular density, cell attachment, and collagen secretion. Considering the results, including favorable mechanical strength, release behavior, antibacterial and cellular properties, gelatin sponges loaded with 2 mg/mL of NO-TS NPs can be suitable for wound dressing applications.

A critical review on the recent trends of photocatalytic, antibacterial, antioxidant and nanohybrid applications of anatase and rutile TiO2 nanoparticles

Titanium dioxide nanoparticles (TiO2 NPs) have become a focal point of research due to their widespread daily use and diverse synthesis methods, including physical, chemical, and environmentally sustainable approaches. These nanoparticles possess unique attributes such as size, shape, and surface functionality, making them particularly intriguing for applications in the biomedical field. The continuous exploration of TiO2 NPs is driven by the quest to enhance their multifunctionality, aiming to create next-generation products with superior performance. Recent research efforts have specifically focused on understanding the anatase and rutile phases of TiO2 NPs and evaluating their potential in various domains, including photocatalytic processes, antibacterial properties, antioxidant effects, and nanohybrid applications. The hypothesis guiding this research is that by exploring different synthesis methods, particularly chemical and environmentally friendly approaches, and incorporating doping and co-doping techniques, the properties of TiO2 NPs can be significantly improved for diverse applications. The study employs a comprehensive approach, investigating the effects of nanoparticle size, shape, dose, and exposure time on performance. The synthesis methods considered encompass both conventional chemical processes and environmentally friendly alternatives, with a focus on how doping and co-doping can enhance the properties of TiO2 NPs. The research unveils valuable insights into the distinct phases of TiO2 NPs and their potential across various applications. It sheds light on the improved properties achieved through doping and co-doping, showcasing advancements in photocatalytic processes, antibacterial efficacy, antioxidant capabilities, and nanohybrid applications. The study concludes by emphasizing regulatory aspects and offering suggestions for product enhancement. It provides recommendations for the reliable application of TiO2 NPs, addressing a comprehensive spectrum of critical aspects in TiO2 NP research and application. Overall, this research contributes to the evolving landscape of TiO2 NP utilization, offering valuable insights for the development of innovative and high-performance products.

Improved cell growth on additively manufactured Ti64 substrates with varying porosity and nanofibrous coating

3T3 Swiss albino mouse cells are often used in biotechnological applications. These cells can grow adherently on suitable surfaces. In our study, they were grown on different titanium substrates, comparing commercially available titanium sheets of grade 1 and grade 2, respectively, with Ti64 which was 3D printed with different porosity in order to identify potential substitutes for common well-plates, which could - in case of 3D printed substrates - be produced in various shapes and dimensions and thus broaden the range of substrates for cell growth in biotechnology and tissue engineering. In addition, thin layers of poly(acrylonitrile) (PAN) nanofibers were electrospun on these substrates to add a nanostructure. The common titanium sheets showed lower cell cover factors than common well plates, which could not be improved by the thin nanofibrous coating. However, the Ti sheets with nanofiber mat coatings showed higher cell adhesion and proliferation than pure PAN nanofiber mats. The 3D printed Ti64 substrates prepared by laser metal fusion, on the other hand, enabled significantly higher proliferation of (66 ± 8)% cover factor after three days of cell growth than well plates which are usually applied as the gold standard for cell cultivation ((48 ± 11)% cover factor under identical conditions). Especially the Ti64 samples with higher porosity showed high cell adhesion and proliferation. Our study suggests investigating such porous Ti64 samples further as a potential future optimum for cell adhesion and proliferation.

Preparation and evaluation in vitro release of sodium alginate/chitosan polyelectrolyte microparticles containing rifampicin and theoretical study using DFT methods

In this work, rifampicin-loaded sodium alginate/chitosan polyelectrolyte microparticles were prepared by the ionotropic gelation technique using CaCl2 as a cross-linking agent. The influence of different sodium alginate and chitosan concentrations on particle size, surface properties, and in vitro release behavior was studied. An infrared spectroscopy investigation verified the lack of any drug-polymer interaction. The microparticles prepared using (30, 50) mg of sodium alginate were spherical while when using 75 mg of sodium alginate, vesicles with round heads and tapered tails were formed. The results showed that the microparticle diameters were between (11.872-35.3645) µm. The amount of rifampicin released and the kinetics of drug release from microparticles were studied, and the results showed that by increasing the concentration of the polymer, the release of the rifampicin from the microparticles decreased. The findings showed that rifampicin release followed zero-order kinetics and that drug release from these particles is frequently influenced by diffusion. The electronic structure and characteristics of the conjugated polymers (sodium alginate/Chitosan) were examined using density functional theory (DFT) and PM3 calculations with Gaussian 9, using the B3LYP, and electronic structure calculations using 6-311 G (d,p). The HOMO and LUMO energy levels are determined as the HOMO's maximum and the LUMO's minimum, respectively.Communicated by Ramaswamy H. Sarma.

Preparation and characterization of 3D bioprinted gelatin methacrylate hydrogel incorporated with curcumin loaded chitosan nanoparticles for in vivo wound healing application

This study developed a biomimetic composite bioink consisting of gelatin methacrylate (GelMA) /chitosan nanoparticles (CSNPs) for extrusion-based 3D bioprinting. Additionally, curcumin(Cur)-loaded nanoparticles were incorporated which increased the proliferation and antibacterial activity of biomimetic skin constructs. The hydrogel, curcumin-loaded NPs, and the biocomposite was characterized chemically and physically. The results indicated proper modified gelatin with tunable physical characteristics, e.g., swelling ratio and biodegradability up to 1200 % and 25 days, respectively. In addition, the characterized CSNPs showed good distribution with a size of 370 nm and a zeta potential of 41.1 mV. We investigated the mechanical and cytocompatibility properties of chitosan nanoparticles encapsulated in hydrogel for emulating an extracellular matrix suitable for skin tissue engineering. CSNPs entrapped in GelMA (15 % w/v) exhibited controlled drug release during 5 days, which was fitted into various kinetic models to study the mass transfer mechanism behavior. Also, the composite hydrogels were effective as a barrier against both gram-positive and gram-negative bacteria at a concentration of 50 μg/ml nanoparticles in GelMA 15 %. Furthermore, the biocomposite was applied on Wistar rats for wound healing. As a result, this study provides a GelMA-NP50-Cur3 scaffold that promotes cell proliferation and decreases microbial infections in wounds.

A review of carbon nanomaterials/bacterial cellulose composites for nanomedicine applications

Carbon nanomaterials (CNMs) mainly include fullerene, carbon nanotubes, graphene, carbon quantum dots, nanodiamonds, and their derivatives. As a new type of material in the field of nanomaterials, it has outstanding physical and chemical properties, such as minor size effects, substantial specific surface area, extremely high reaction activity, biocompatibility, and chemical stability, which have attracted widespread attention in the medical community in the past decade. However, the single use of carbon nanomaterials has problems such as self-aggregation and poor water solubility. Researchers have recently combined them with bacterial cellulose to form a new intelligent composite material to improve the defects of carbon nanomaterials. This composite material has been widely synthesized and used in targeted drug delivery, biosensors, antibacterial dressings, tissue engineering scaffolds, and other nanomedicine fields. This paper mainly reviews the research progress of carbon nanomaterials based on bacterial cellulose in nanomedicine. In addition, the potential cytotoxicity of these composite materials and their components in vitro and in vivo was discussed, as well as the challenges and gaps that need to be addressed in future clinical applications.

Microcurrent Cloth-Assisted Transdermal Penetration and Follicular Ducts Escape of Curcumin-Loaded Micelles for Enhanced Wound Healing

Purpose

Larger nanoparticles of bioactive compounds deposit high concentrations in follicular ducts after skin penetration. In this study, we investigated the effects of microcurrent cloth on the skin penetration and translocation of large nanoparticle applied for wound repair applications.

Methods

A self-assembly of curcumin-loaded micelles (CMs) was prepared to improve the water solubility and transdermal efficiency of curcumin. Microcurrent cloth (M) was produced by Zn/Ag electrofabric printing to facilitate iontophoretic transdermal delivery. The transdermal performance of CMs combined with M was evaluated by a transdermal system and confocal microscopy. The CMs/iontophoretic combination effects on nitric oxide (NO) production and inflammatory cytokines were evaluated in Raw 264.7 cells. The wound-healing property of the combined treatment was assessed in a surgically created full-thickness circular wound mouse model.

Results

Energy-dispersive X-ray spectroscopy confirmed the presence of Zn/Ag on the microcurrent cloth. The average potential of M was measured to be +214.6 mV in PBS. Large particle CMs (CM-L) prepared using surfactant/cosurfactant present a particle size of 142.9 nm with a polydispersity index of 0.319. The solubility of curcumin in CM-L was 2143.67 μg/mL, indicating 250-fold higher than native curcumin (8.68 μg/mL). The combined treatment (CM-L+M) demonstrated a significant ability to inhibit NO production and increase IL-6 and IL-10 secretion. Surprisingly, microcurrent application significantly improved 20.01-fold transdermal performance of curcumin in CM-L with an obvious escape of CM-L from follicular ducts to surrounding observed by confocal microscopy. The CM-L+M group also exhibited a better wound-closure rate (77.94% on day 4) and the regenerated collagen intensity was approximately 2.66-fold higher than the control group, with a closure rate greater than 90% on day 8 in vivo.

Conclusion

Microcurrent cloth play as a promising iontophoretic transdermal drug delivery accelerator that enhances skin penetration and assists CMs to escape from follicular ducts for wound repair applications.

Electrospun fibers for the treatment of skin diseases

Skin diseases are among the most common diseases in the global population and with the growth of the aging population, they represent an increasing burden to healthcare systems worldwide. Even though they are rarely life-threatening, the suffering for those affected is high due to the visibility and physical discomfort related to these diseases. Typical symptoms of skin diseases include an inflamed, swollen or itchy skin, and therefore, there is a high demand for effective therapy options. In recent years, electrospinning has attracted considerable interest in the field of drug delivery. The technique allows producing multifunctional drug-loaded fibrous patches from various natural and synthetic polymers with fiber diameters in the nano- and micrometer range, suitable for the treatment of a wide variety of skin diseases. The great potential of electrospun fiber patches not only lies in their tunable drug release properties and the possibility to entrap a variety of therapeutic compounds, but they also provide physical and mechanical protection to the impaired skin area, exhibit a high surface area, allow gas exchange, absorb exudate due to their porous structure and are cytocompatible and biodegradable. In the case of wound healing, cell adhesion is promoted due to the resemblance of the electrospun fibers to the structure of the native extracellular matrix. This review gives an overview of the potential applications of electrospun fibers in skin therapy. In addition to the treatment of bacterial, diabetic and burn wounds, focus is placed on inflammatory diseases such as atopic dermatitis and psoriasis, and therapeutic options for the treatment of skin cancer, acne vulgaris and herpes labialis are discussed. While we aim to emphasize the great potential of electrospun fiber patches for the treatment of skin diseases with this review paper, we also highlight challenges and limitations of current research in the field.

Green synthesis, characterization of melatonin-like drug bioconjugated CoS quantum dots and its antiproliferative effect on different cancer cells

BACKGROUND

Quantum dots are usually particles smaller than 100 nm and have a low toxic effect. This study aimed to bioconjugate the anticancer effective melatonin agonist to quantum dots and demonstrate its effects in two cancer lines. This is the first study that aims to examine the anticancer activity of ramelteon bioconjugation to quantum dots, providing a new perspective on the use of Melatonin and its derivatives in cancer.

METHODS AND RESULTS

For this purpose, first of all, cobalt sulfide (CoS) quantum dots were synthesized, bioconjugated and characterized with Punica granatum extract by green synthesis method. The effects of synthesized nanomaterials on neuroblastoma and prostate cancer cells were investigated. It was noted that nanomaterials reduced cell viability by 50% in neuroblastoma and prostate cancer lines at a dose of 50 µg/mL. Ramelteon bioconjugated nanomaterials reduced cancer cell viability by 1.4 times more than free melatonin. CoS quantum dots were determined to double the oxidative stress in the neuroblastoma cell line compared to the control, while no change was observed in prostate cancer. In the gene expression findings, it was observed that CoS nanoparticles caused an increase in the expression levels of apoptosis-related genes in the neuroblastoma cell line and induced key protein expression levels of pathways such as ROR-alpha in the prostate cancer cell line.

CONCLUSION

As a result, it was observed that the viability of the neuroblastoma cell line decreased with apoptosis induced by oxidative stress, while this effect was observed in the DU-145 cell line via the ROR-alpha pathway.

Fabrication of an Artificial Pulley Based on Electrospun Composite Polyurethane/Polycaprolactone Nanofibers for Hand Surgery: Structural, Mechanical, In Vitro, and In Vivo Examinations

Injuries to the hand's flexor pulley system can be debilitating, causing pain and restricting movement of the affected finger(s). The creation of a biocompatible artificial pulley could potentially alleviate some of the complications associated with current surgical treatments. In this study, a biocompatible artificial pulley was fabricated by using polycaprolactone (PCL) and polyurethane (PU) in the form of an electrospun nanofiber structure. All scaffolds were structurally analyzed using FESEM imaging, porosity, FTIR, and DSC examinations. Mechanical properties were evaluated, and in vitro studies were conducted on the degradation rate, swelling ratio, and toxicity. Immune response to fabricated scaffolds was evaluated by implanting them under the skin of rats for further pathological examination. All scaffolds exhibited a nanoscale structure and high porosity without any undesirable functional groups. The 25% PCL scaffold showed 17%, 20%, 80%, 17%, and 70% significant increases in Fmax, final stress, final strain, Young's modulus, and elongation percentage, respectively. In fact, the PCL25% scaffold demonstrated more than 100% improvement in mechanical properties compared to those of A2 and A4 natural pulleys. Additionally, all scaffold structures showed cell viability similar to that of the control sample. The study suggests that scaffolds made of 25% PCL hold promise as effective artificial pulleys for reconstructing the flexor tendon pulley system in cases of injury.

Enhanced immune responses in dexamethasone immunosuppressed male rats supplemented with herbal extracts, chitosan nanoparticles, and their conjugates

Nowadays, the world is challenged with highly contagious diseases, one of their preliminary virulence mechanisms is the suppression of innate immunity. Therefore, promoting natural immunity is a good precautionary strategy. we investigated and compared the effects of several natural herbal extracts -Moringa oleifera, Ziziphus spina christi, and Saussurea costus, and chitosan nanoparticles (CS NPs)- as well as conjugated extracts with CS NPs on the immunological parameters of dexamethasone immunosuppressed (IS) male rats. The plant extracts were assessed for total flavonoids, phenolics, and antioxidant activity. The CS NPs and their conjugates were characterized using particles size, zeta potentials, and Fourier-transform infrared spectroscopy analyses. The chemical analysis of the plant extracts, CS NPs, and their conjugates was performed using energy dispersive X-ray fluorescence, and their cytotoxicity was evaluated in human lung fibroblast (WI-38) and human embryonic kidney (HEK-293) cell lines. For in vivo evaluations, 72 adult male rats were divided into 9 groups: control, IS, three plant extracts, CS, and conjugates of the three plant extracts and CS NPs. Oral supplementation (day after day) lasted for 28 days. Liver, kidney, and spleen tissue samples were collected for histopathology and Ki-67 expression analyses. The results revealed that the plant extracts and CS improved the total leukocyte counts, complement 3, complement 4, interferon-gamma, and tumor necrosis factor levels at day 28. However, the plant extract-CS NPs conjugates faster and have higher immunostimulatory effects at day 14. Furthermore, the atrophied white pulp of the spleen induced by dexamethasone was alleviated, and Ki-67 expression was elevated in all the treated groups. Conclusively, the conjugates of Moringa oleifera, Ziziphus spina christi, and Saussurea costus extract with CS NPs demonstrated more potent and rapid immune responses at lower doses and concentrations compared to the plant extracts or CS NPs alone, without causing liver or kidney injuries. Thus, supplementation of these conjugated plant extracts at lower doses and concentrations is recommended to improve immunity while considering safety considerations.

Ultrasonically assisted hydrothermal synthesis of tungsten(VI) oxide-TiO2 nanocomposites for enhanced photocatalytic degradation of non-narcotic drug paracetamol under natural solar light: insights into degradation pathway, mechanism, and toxicity assessment

Photocatalytic degradation of pharmaceutical residues through natural solar radiation represents a green and economical treatment process. In this work, ultrasonically assisted hydrothermal synthesis of WO3-TiO2 nanocomposite was carried out at 140-150 °C for 5 h and calcinated at 600 °C. The structural and optical properties of the synthesized material were investigated using techniques like XRD, FESEM/EDX, HRTEM, BET surface area, UV-DRS optical analysis, and photocurrent response. The band gap of TiO2 was successfully reduced from 3.0 to 2.54 eV and thus making it effective under solar light. Complete degradation of paracetamol (50 ppm and natural pH of 6.5) was achieved in 3.5 h under natural sunlight at catalyst dose of 0.5 g/l. The extent of mineralization was evaluated by measuring the COD reduction. Based on the degradation products identified by GC-MS/LC-TOF-MS, the degradation process under natural solar-light could be interpreted to initiate through OH. radical species. The toxicity removal of the treated paracetamol solution under natural solar-light was evaluated by the seed germination test using Spinacia oleracea seeds and exhibited 66.70% seed germination, confirming the reduction in toxicity. The enhanced photocatalytic efficiency of the nanocomposite is attributed to the higher surface area, low rutile content, lower band gap, and incorporation of WO3, which led to an extended absorption range and a slower rate of electron-hole recombination. The technical insights presented in this research offer a feasible approach for utilizing natural solar light driven photocatalysis for wastewater treatment in an efficient and sustainable way. The proposed degradation pathway, and seed germination test (toxicity removal) of the treated paracetamol solution under natural sunlight, has not been previously evaluated.

Fabrication of ordered layered SnO2/TiO2 heterostructures and their photocatalytic performance for methyl blue degradation

The rapid growth in population and industrialization has given rise to serious environmental issues, especially the water pollution. Photocatalysis with the assist of semiconductor photocatalysts has been considered as an advanced oxidation technique for degrading a variety of pollutants under solar irradiation. In this work, we have fabricated SnO2-TiO2 heterostructures with different ordered layers of SnO2 and TiO2 via the sol-gel dip-coating technique and utilized in photocatalysis for degradation of methyl blue dye under UV irradiation. The influence of the layer's position on SnO2 and TiO2 properties is investigated via the various techniques. The grazing incidence X-ray diffraction (GIXRD) analysis reveals that the as-prepared films exhibit pure anatase TiO2 and kesterite SnO2 phases. The 2SnO2/2TiO2 heterostructure exhibit the maximum crystallite size and smallest deviation from the ideal structure. Scanning electron microscopy cross-section images manifest good adhesion of the layers to each other and to the substrate. Fourier transform infrared spectroscopy reveals the characteristic vibration modes of SnO2 and TiO2 phases. UV-visible spectroscopy measurements indicate that all films exhibit high transparency (T = 80%) and the SnO2 film reveals a direct band gap of 3.6 eV, while the TiO2 film exhibits an indirect band gap of 2.9 eV. The optimal 2SnO2/2TiO2 heterostructure film revealed best photocatalytic degradation performance and the reaction rate constant for methylene blue solution under UV irradiation. This work will trigger the development of highly efficient heterostructure photocatalysts for environmental remediation.

Fabrication and multiscale modeling of polycaprolactone/amniotic membrane electrospun nanofiber scaffolds for wound healing

BACKGROUND

Enhancing the efficiency of cell-based skin tissue engineering (TE) approaches is possible via designing electrospun scaffolds possessing natural materials like amniotic membrane (AM) with wound healing characteristics. Concentrating on this aim, we fabricated innovative polycaprolactone (PCL)/AM scaffolds through the electrospinning process.

METHODS

The manufactured structures were characterized by employing scanning electron microscope (SEM), attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, tensile testing, Bradford protein assay, etc. In addition, the mechanical properties of scaffolds were simulated by the multiscale modeling method.

RESULTS

As a result of conducting various tests, it was concluded that the uniformity and distribution of fibers decreased with an increase in the amniotic content. Furthermore, PCL-AM scaffolds contained amniotic and PCL characteristic bands. In the case of protein release, greater content of AM led to the release of higher amounts of collagen. Tensile testing revealed that scaffolds' ultimate strength increased when the AM content augmented. The multiscale modeling demonstrated that the scaffold had elastoplastic behavior. In order to assess cellular attachment, viability, and differentiation, human adipose-derived stem cells (ASCs) were seeded on the scaffolds. In this regard, SEM and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assays showed significant cellular proliferation and viability on the proposed scaffolds, and these analyses illustrated that higher cell survival and adhesion could be achieved when scaffolds possessed a larger amount of AM. After 21 days of cultivation, particular keratinocyte markers, such as keratin I and involucrin, were identified through utilizing immunofluorescence and real-time polymerase chain reaction (PCR) tests. The markers' expressions were higher in the PCL-AM scaffold with a ratio of 90:10 v v-1 compared with the PCL-epidermal growth factor (EGF) structure. Moreover, the presence of AM in the scaffolds resulted in the keratinogenic differentiation of ASCs even without employing EGF. Consequently, this state-of-the-art experiment suggests that the PCL-AM scaffold can be a promising candidate in skin bioengineering.

CONCLUSION

This study showed that mixing AM with PCL, a widely used polymer, in different concentrations can overcome PCL disadvantages such as high hydrophobicity and low cellular compatibility.

Investigation of the antitumor effect on breast cancer cells of the electrospun amygdalin-loaded poly(l-lactic acid)/poly(ethylene glycol) nanofibers

In this study, PLA/PEG nanofibers (NFs) loaded with amygdalin (AMG) and bitter almond kernels extract were produced by electrospinning to prevent local breast cancer recurrence, and the effect of produced NFs on the MCF-7 cell line was investigated in vitro. The electrospun NFs were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), thermal analysis (DSC) and tensile strength and physical analyzes were performed. Loading of AMG to nanofibers increased fiber diameters from 827.93 ± 174.507 nm to 1855.32 ± 291.057 μm. When drug release results were analyzed, the NFs showed a controlled release profile extending up to 10 h. The encapsulation efficiency of AMG-loaded NFs was calculated at 100 ± 0,01 %, 94 ± 0,02 %, and 88 ± 0,02 %. When in vitro cytotoxicity results were analyzed, showed that all NFs are effective in inducing cytotoxicity against MCF-7 breast cancer cells. Importantly, 20 mg AMG-loaded NFs displayed effectively higher cytotoxic effects against breast cancer cells relative to the other NFs. Considering all the results, AMG-loaded NFs can give sustained release of drugs at the local sites. Therefore, AMG-loaded nanofibers can reduce the risk of local recurrence of cancer after surgery and can be directly implanted into solid tumor cells for treatment.

Modification of the Structure and Linear/Nonlinear Optical Characteristics of PVA/Chitosan Blend through CuO Doping for Eco-Friendly Applications

The solution casting technique is utilized to fabricate blank and CuO-doped polyvinyl alcohol/chitosan (PVA/CS) blends for eco-friendly applications. The structure and surface morphologies of prepared samples were explored by Fourier transform infrared (FT-IR) spectrophotometry and scanning electron microscopy (SEM), respectively. FT-IR analysis reveals the incorporation of CuO particles within the PVA/CS structure. SEM analysis exposes the well-dispersion of CuO particles in the host medium. The linear/nonlinear optical characteristics were found on the basis of UV-visible-NIR measurements. The transmittance of the PVA/CS decreases upon CuO increasing to 20.0 wt%. The optical bandgap (E_{g dir.}/E_{g ind.}) decreases from 5.38/4.67 eV (blank PVA/CS) to 3.72/3.12 eV (20.0 wt% CuO-PVA/CS). An obvious improvement in the optical constants of the PVA/CS blend is achieved by CuO doping. The Wemple-DiDomenico (WDD) and Sellmeier oscillator models were utilized to examine the CuO role dispersion behavior of the PVA/CS blend. The optical analysis shows clear enrichment of the optical parameters of the PVA/CS host. The novel findings in the current study nominate CuO-doped PVA/CS films for applications in linear/nonlinear optical devices.

Green synthesized polyvinylpyrrolidone/titanium dioxide hydrogel nanocomposite modified with agarose macromolecules for sustained and pH-responsive release of anticancer drug

Cancer, as one of the most challenging diseases of the last century, has a significant number of patients and deaths every year. Various strategies have been explored for the treatment of cancer. Chemotherapy is one of the methods of treating cancer. Doxorubicin is one of the compounds used in chemotherapy to kill cancer cells. Due to their unique properties and low toxicity, metal oxide nanoparticles are effective in combination therapy and increase the effectiveness of anti-cancer compounds. The limited in vivo circulatory period, poor solubility, and inadequate penetration of doxorubicin (DOX) restrict its use in cancer treatment, notwithstanding its attractive characteristics. It is possible to circumvent some of the difficulties in cancer therapy by using green synthesized pH-responsive nanocomposite consisting of polyvinylpyrrolidone (PVP), titanium dioxide (TiO₂) modified with agarose (Ag) macromolecules. TiO₂ incorporation into the PVP-Ag nanocomposite resulted in limited increased loading and encapsulation efficiencies from 41 % to 47 % and 84 % to 88.5 %, respectively. DOX diffusion among normal cells is prevented by the PVP-Ag-TiO₂ nanocarrier at pH = 7.4, though the acidic intracellular microenvironments activate the PVP-Ag-TiO₂ nanocarrier at pH = 5.4. Characterization of the nanocarrier was performed using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectrophotometry, field emission scanning electron microscopy (FE-SEM), dynamic light scattering (DLS), and zeta potential. The average particle size and the zeta potential of the particles showed values of 349.8 nm and +57 mV, respectively. In vitro release after 96 h showed a release rate of 92 % at pH 7.4 and a release rate of 96 % at pH 5.4. Meanwhile, the initial release after 24 h was 42 % for pH 7.4 and 76 % for pH 5.4. As shown by an MTT analysis on MCF-7 cells, the toxicity of DOX-loaded PVP-Ag-TiO₂ nanocomposite was substantially greater than that of unbound DOX and PVP-Ag-TiO₂. After integrating TiO₂ nanomaterials into the PVP-Ag-DOX nanocarrier, flow cytometry data showed a greater stimulation of cell death. These data indicate that the DOX-loaded nanocomposite is a suitable alternative for drug delivery systems.

Assessment of synthesized chitosan/halloysite nanocarrier modified by carbon nanotube for pH-sensitive delivery of curcumin to cancerous media

Constructing a system to carry medicine for more effective remedy of cancer has been a leading challenge, as the number of cancer cases continues to increase. In this present research, a curcumin-loaded chitosan/halloysite/carbon nanotube nanomixture was fabricated by means of water/oil/water emulsification method. The drug loading efficiency (DL) and entrapment efficiency (EE), as a result, reached 42 % and 88 %, respectively and FTIR and XRD analysis confirmed the bonding between the drug and nanocarrier. Morphological observation through FE-SEM and characterization through DLS analysis demonstrated that the average size of nanoparticles is 267.37 nm. Assessment of release within 96 h in pH 7.4 and 5.4 showed sustained release. For more investigation, release data was analyzed by diverse kinetic models to understand the mechanism in the release procedure. An MTT assay was also carried out, and the results illustrated apoptosis induction on MCF-7 cells and exhibited ameliorated cytotoxicity of the drug-loaded nanocomposite compared to the free curcumin. These findings suggest that the unique pH-responsive chitosan/halloysite/carbon nanotube nanocomposite might make a good option for drug delivery systems, particularly for the cancer treatment.

Estrogen adsorption from an aqueous solution on the chitosan nanoparticles

In this research, chitosan nanoparticles as an efficient and reusable adsorbent with adsorption capacity of 5.79 mg/g, surface area of 62 m²/g and pH_pzc of 8.07 were applied to remove the ethinylestradiol (as a sample of estrogen) from an aqueous wastewater. The chitosan nanoparticles were characterized by SEM, XRD and FT-IR analyses. Four independent variables involving contact time, adsorbent dosage, pH, and initial concentration of estrogen were applied to design the experiments by Design Expert software (CCD under RSM). In fact, number of experiments was minimized and the operating conditions were optimized for the maximum estrogen removal. The results indicated that three independent variables (contact time, adsorbent dosage, and pH) increment increased the estrogen removal while the estrogen initial concentration enhancement decreased the removal due to the concentration polarization phenomenon. The optimum conditions for the estrogen removal (92.50 %) on the chitosan nanoparticles were found at contact time of 220 min, adsorbent dosage of 1.45 g/l, pH of 7.3 and estrogen initial concentration of 5.7 mg/l. Moreover, the Langmuir isotherm and pseudo-second order models could properly legitimize estrogen adsorption process on the chitosan nanoparticles.