Quaternized chitosan-stabilized copper sulfide nanoparticles for cancer therapy

The regulation of CuSNPs' interface for further enhancing mechanical and photothermal conversion properties of chitosan/@CuSNPs hybrid fibers

Our previous study has demonstrated that the microstructure of copper sulfide nanoparticles (CuSNPs) can be controlled to enhance mechanical and photothermal conversion properties of chitosan (CS)/CuSNPs hybrid fibers. However, achieving optimal dispersion and compatibility of CuSNPs within a CS matrix remains a challenge, this study aims to improve dispersion and compatibility by modifying the CuSNPs' interface, thereby enhancing mechanical and photothermal conversion properties of hybrid fibers. The interfaces of @CuSNPs (CuS@Xylan NPs, CuS@SA NPs, and CuS@PEG NPs) contain hydroxyl groups, facilitating the hydrogen bonds formation with the CS matrix. The dispersibility is further enhanced by the synergistic effect of xylan and SA's anionic charges with cationic chitosan. Notably, the viscosity of the CS/@CuSNPs hybrid spinning solution is significantly enhanced, resulting in improved breaking strength for initial hybrid fibers. Specifically, the breaking strength of CS/CuS@Xylan NPs hybrid fibers reaches 1.4 cN/dtex, exhibiting a 42.86 % and 20.6 % increase over CS and CS/CuSNPs hybrid fibers. Simultaneously, the CS/CuS@Xylan NPs hybrid fibers exhibit exceptional photothermal conversion performance, surpassing that of CS fibers by 5.2 times and CS/CuSNPs hybrid fibers by 1.4 times. The regulation of interface modification is an efficient approach to enhance the tensile strength and photothermal conversion properties of CS/CuSNPs hybrid fibers.

Engineered praseodymium sulfide nanocarrier and supramolecular association of anticancer drug for effective delivery to breast cancer cells

Metal sulfide nanoparticles are synthesized for their biomedical applications, including cancer drug targeting. This paper reports a novel nanocomposite made of praseodymium sulfide nanoparticles and poly-cyclodextrin. The praseodymium sulfide nanoparticles were synthesized hydrothermal, autoclaving the nitrate precursors at 150 °C for 18 hours. The material is characterized using XRD and shows an orthorhombic crystal system with high crystallinity. The size and morphology of the nanomaterial were optimized. The material shows a rod-shaped morphology, as seen in the TEM image, with 150 ± 3 nm length and 25 ± 5 nm width. Particle size analysis supports this size range. The colloidal particles were stable in the aqueous medium without precipitation at neutral pH. The elements in the material in the polymer-coated form and their electronic states are studied by X-ray photoelectron spectroscopy. Thermogravimetry confirms that the material contains about 18.5% of the weight of the polymer. The material has an observable magnetic property at room temperature due to the praseodymium element. The UV-vis-NIR absorption spectrum of the material shows a long absorption range that extends to 1200 nm. The drug 5-fluorouracil is encapsulated in the nanoparticles through host: guest association, and its release profile is analyzed. The release is modulated at a slightly acidic pH, indicating the pH-tunability. The nanoparticles and 5-fluorouracil were taken in the w/w ratio of 2:1 (2/1 mg in 1 mL of deionized water). Further, the in vitro anticancer activity of the drug-encapsulated material is screened on breast cancer and non-cancerous cell lines. The IC50 values are reported, and the advantageous properties of the material as drug carriers are discussed.

Chitosan/copper sulfide nanoparticles (CS/CuSNPs) hybrid fibers with improved mechanical and photo-thermal conversion properties via tuning CuSNPs' morphological structures

Conventional textiles are inadequate for maintaining warmth in extremely cold conditions. Therefore, the development of photo-thermal fibers for personal thermal management textiles has emerged as an urgent need. Herein, novel chitosan/copper sulfide nanoparticles (CS/CuSNPs) hybrid fibers with photo-thermal function were fabricated successfully. Significantly, our study demonstrated that the tensile and photo-thermal conversation properties of the CS/CuSNPs hybrid fibers could be effectively regulated by altering the CuSNPs` morphological structures. Compared with other CuSNPs (tube-like, sphere-like, and flower-like), the plate-like CuSNPs with smooth surfaces and uniform nanometer size played a significant role by scattering incident light in the fibers as a secondary light source for CuSNPs absorbance. Thus, under IR light irradiation at a power density of 1.0 W/cm2, the surface temperature of CS/0.1 wt% plate-like CuSNPs hybrid fibers sharply increased by 27.6 °C, which was more than 4 times of the pure CS fibers. And the breaking strength and initial modulus of CS/0.1 wt% plate-like CuSNPs hybrid fibers increased by more than 18.37 and 6.88 % compared with the nascent CS fibers. This study develops a novel and effective strategy to tune the photo-thermal and tensile properties of CS hybrid fibers without incorporating more content or additives.

Plasmonic and Photothermal Effects of CuS Nanoparticles Biosynthesized from Acid Mine Drainage with Potential Drug Delivery Applications

In this work, the plasmonic and photothermal effects of CuS nanoparticles biosynthesized from acid mine drainage (AMD) were studied. CuS were formed by delivering the H2S generated by a sulfidogenic bioreactor to an off-line system containing the AMD. The precipitates collected after contact for an hour were washed and physico-chemically characterized, showing a nanoparticle with a mean diameter of 33 nm, crystalline nature and semiconductor behavior with a direct band gap of 2.2 eV. Moreover, the CuS nanoparticles exhibited localized surface plasmonic resonance in the near infrared range, with a high absorption band centered at 973 nm of wavelength, which allowed an increase in the temperature of the surrounding media under irradiation. Finally, the cytotoxicity of the CuS nanoparticles as well as their potential use as part of drug delivery platforms were investigated.

A Review of Chondroitin Sulfate's Preparation, Properties, Functions, and Applications

Chondroitin sulfate (CS) is a natural macromolecule polysaccharide that is extensively distributed in a wide variety of organisms. CS is of great interest to researchers due to its many in vitro and in vivo functions. CS production derives from a diverse number of sources, including but not limited to extraction from various animals or fish, bio-synthesis, and fermentation, and its purity and homogeneity can vary greatly. The structural diversity of CS with respect to sulfation and saccharide content endows this molecule with distinct complexity, allowing for functional modification. These multiple functions contribute to the application of CS in medicines, biomaterials, and functional foods. In this article, we discuss the preparation of CS from different sources, the structure of various forms of CS, and its binding to other relevant molecules. Moreover, for the creation of this article, the functions and applications of CS were reviewed, with an emphasis on drug discovery, hydrogel formation, delivery systems, and food supplements. We conclude that analyzing some perspectives on structural modifications and preparation methods could potentially influence future applications of CS in medical and biomaterial research.

Hollow copper sulfide nanoparticles carrying ISRIB for the sensitized photothermal therapy of breast cancer and brain metastases through inhibiting stress granule formation and reprogramming tumor-associated macrophages

As known, the benefits of photothermal therapy (PTT) are greatly limited by the heat tolerance of cancer cells resulting from overexpressed heat shock proteins (HSPs). Then HSPs further trigger the formation of stress granules (SGs) that regulate protein expression and cell viability under various stress conditions. Inhibition of SG formation can sensitize tumor cells to PTT. Herein, we developed PEGylated pH (low) insertion peptide (PEG-pHLIP)-modified hollow copper sulfide nanoparticles (HCuS NPs) encapsulating the SG inhibitor ISRIB, with the phase-change material lauric acid (LA) as a gate-keeper, to construct a pH-driven and NIR photo-responsive controlled smart drug delivery system (IL@H-PP). The nanomedicine could specifically target slightly acidic tumor sites. Upon irradiation, IL@H-PP realized PTT, and the light-controlled release of ISRIB could effectively inhibit the formation of PTT-induced SG to sensitize tumor cells to PTT, thereby increasing the antitumor effect and inducing potent immunogenic cell death (ICD). Moreover, IL@H-PP could promote the production of reactive oxygen species (ROS) by tumor-associated macrophages (TAMs), repolarizing them towards the M1 phenotype and remodeling the immunosuppressive microenvironment. In vitro/vivo results revealed the potential of PTT combined with SG inhibitors, which provides a new paradigm for antitumor and anti-metastases.

Applications and perspectives of quaternized cellulose, chitin and chitosan: A review

Recently, increasing attention has been paid to natural polysaccharides for their low cost, biocompatibility and biodegradability. Quaternization is a modification method to improve the solubility and antibacterial ability of natural polysaccharides. Water-soluble derivatives of cellulose, chitin and chitosan offer the prospect of diverse applications in a wide range of fields, such as antibacterial products, drug delivery, wound healing, sewage treatment and ion exchange membranes. By combining the inherent properties of cellulose, chitin and chitosan with the inherent properties of the quaternary ammonium groups, new products with multiple functions and properties can be obtained. In this review, we summarized the research progress in the applications of quaternized cellulose, chitin and chitosan in recent five years. Moreover, ubiquitous challenges and personal perspectives on the further development of this promising field are also discussed.

Tumor microenvironment penetrating chitosan nanoparticles for elimination of cancer relapse and minimal residual disease

Chitosan and its derivatives are among biomaterials with numerous medical applications, especially in cancer. Chitosan is amenable to forming innumerable shapes such as micelles, niosomes, hydrogels, nanoparticles, and scaffolds, among others. Chitosan derivatives can also bring unprecedented potential to cross numerous biological barriers. Combined with other biomaterials, hybrid and multitasking chitosan-based systems can be realized for many applications. These include controlled drug release, targeted drug delivery, post-surgery implants (immunovaccines), theranostics, biosensing of tumor-derived circulating materials, multimodal systems, and combination therapy platforms with the potential to eliminate bulk tumors as well as lingering tumor cells to treat minimal residual disease (MRD) and recurrent cancer. We first introduce different formats, derivatives, and properties of chitosan. Next, given the barriers to therapeutic efficacy in solid tumors, we review advanced formulations of chitosan modules as efficient drug delivery systems to overcome tumor heterogeneity, multi-drug resistance, MRD, and metastasis. Finally, we discuss chitosan NPs for clinical translation and treatment of recurrent cancer and their future perspective.

Emerging theranostics to combat cancer: a perspective on metal-based nanomaterials

OBJECTIVE

Theranostics, encompassing diagnostics and therapeutics, has emerged as a critical component of cancer treatment. Metal-based theranostics is one such next-generation nanotechnology-based drug delivery system with a myriad of benefits in pre-clinical and clinical medication for the deadly diseases like cancer, where early detection can actually be life-saving.

SIGNIFICANCE

Metal theranostics have shown promising outcomes in terms of anticancer medication monitoring, targeted drug delivery, and simultaneous detection and treatment of early-stage cancer.

METHODS

For collection of literature data, different search engines including Google scholar, SciFinder, PubMed, ScienceDirect have been employed. With key words like, cancer, theranostics, metal nanoparticles relevant and appropriate data have been generated.

RESULTS

Noninvasive administration of the active drug is made possible by theranostics nanoparticulate systems' ability to aggregate at the tumor site and offer morphological and biochemical characteristics of the tumor site. The recent advancement of metal-based theranostics including metallic nanoparticles, metal oxides, metal sulfides, nanocomposites, etc. has been explored at length in this article.

CONCLUSION

The review highlights emerging applications in terms of molecular imaging, targeted therapy and different diagnostic approaches of metal theranostics. Possible challenges faced by nanotheranostics in terms of clinical immersion and toxicological aspects which need to be addressed at depth are also discussed at the end.

Water Saturated with Pressurized CO2 as a Tool to Create Various 3D Morphologies of Composites Based on Chitosan and Copper Nanoparticles

Methods for creating various 3D morphologies of composites based on chitosan and copper nanoparticles stabilized by it in carbonic acid solutions formed under high pressure of saturating CO2 were developed. This work includes a comprehensive analysis of the regularities of copper nanoparticles stabilization and reduction with chitosan, studied by IR and UV-vis spectroscopies, XPS, TEM and rheology. Chitosan can partially reduce Cu2+ ions in aqueous solutions to small-sized, spherical copper nanoparticles with a low degree of polydispersity; the process is accompanied by the formation of an elastic polymer hydrogel. The resulting composites demonstrate antimicrobial activity against both fungi and bacteria. Exposing the hydrogels to the mixture of He or H2 gases and CO2 fluid under high pressure makes it possible to increase the porosity of hydrogels significantly, as well as decrease their pore size. Composite capsules show sufficient resistance to various conditions and reusable catalytic activity in the reduction of nitrobenzene to aniline reaction. The relative simplicity of the proposed method and at the same time its profound advantages (such as environmental friendliness, extra purity) indicate an interesting role of this study for various applications of materials based on chitosan and metals.

Photothermal effects of CuS-BSA nanoparticles on H22 hepatoma-bearing mice

The objective of this study was to evaluate the in vivo application and photothermal ablation effects and mechanism of copper sulfide nanoparticles (CuS NPs) in hepatocellular carcinoma (HCC). Sheet-like CuS-BSA NPs with a particle size of 30 nm were synthesized using bovine serum albumin (BSA) as a biological modifier, and were physically characterized. To provide a reference range for the biosafety dose of CuS-BSA NPs, 36 male Kunming mice were randomly assigned into six groups. Different one-time doses of CuS-BSA NPs were injected via tail vein injection, and the potential damages of liver, kidney and spleen were observed 14 days later. To evaluate the in vivo photothermal effect of CuS-BSA NPs, 48 male Kunming mice were used to establish the H22 hepatoma-bearing mouse model and were randomly assigned into six groups. CuS-BSA NPs (600 μg/kg) were injected via tail vein or intratumoral injection. Irradiations were performed 30 min after injection, with a 980 nm near-infrared laser (2.0 W/cm²) for 10 min once a week for 3 weeks. The results indicated that the CuS-BSA NPs had good dispersibility in three different solvents and had a strong absorption peak at 980 nm. The heating curves demonstrated that the photothermal effects of CuS-BSA NPs aqueous solution exhibited concentration dependence and power density dependence. In the in vivo experiment, when the doses of CuS-BSA NPs were in the range of 1800–7,200 μg/kg, the thymus index and spleen index of mice were not significantly different from those of the control group, and the structures of liver, kidney and spleen were intact without remarkable pathological changes. A lower dose of CuS-BSA NPs (600 μg/kg) could effectively inhibit tumor growth in H22 hepatoma-bearing mice at 980 nm NIR. Moreover, under the near-infrared laser irradiation, both in the tail vein injection group and the intratumoral injection group, a large area of necrosis in the tumor tissue, as well as the up-regulation of apoptotic proteins including cleaved caspase-3 and cleaved caspase-9 were observed. CuS-BSA NPs are promising photothermal agents in the photothermal therapy of cancer.

CuS NP-based nanocomposite with photothermal and augmented-photodynamic activity for magnetic resonance imaging-guided tumor synergistic therapy

Although many treatments have been developed for oncotherapy, the lack of effective imaging guidance in the therapeutic process is still an urgent problem to be solved. In this study, magnetic resonance contrast agent (Gd) chelated on CuS nanoparticles and glucose oxidase (GOx) were coloaded into mesoporous silica nanoparticles (MSNs) to form GOx-Gd-CuS@MSNs, in which the Gd provided magnetic resonance imaging (MRI) for therapeutic process monitor while GOx could catalyze the generation of H₂O₂ to enhance the photodynamic therapy (PDT). The in vitro results show that under near-infrared (NIR) laser irradiation (2 W·cm^-2, 5 min), temperature rapidly increased by approximately 30 °C for the accumulation of heat. At the same time, GOx on GOx-Gd-CuS@MSNs effectively consumed glucose to produce a large amount of H₂O₂, which was used to augment PDT through producing highly toxic hydroxyl radicals (·OH) and singlet oxygen (¹O₂). The photothermal and augmented-photodynamic could induce apoptosis and death of tumor cells. More importantly, the study found that GOx-Gd-CuS@MSNs had MRI performance, which provided imaging guidance during the treatment process, and it can monitor the diffusion of water molecules in the tumor tissue during the treatment and microcirculation perfusion of capillary network. These results indicate that the nanomaterial produced significant synergistic therapeutic effects through photothermal and photodynamic forces, meanwhile showed excellent spatial resolution and deep tissue penetration in imaging.

Self-assembled NIR-responsive MoS2@quaternized chitosan/nanocellulose composite paper for recyclable antibacteria

Paper products are widely used in daily life, while the lack of antibacterial activity has made them become some disease transmission media. Herein, we introduced NIR-responsive molybdenum disulfide nanosheets (MoS₂) to endow nanocellulose paper antibacterial activity by electrostatic self-assembly with quaternized chitosan (QCS). Firstly, the MoS₂ nanosheets were exfoliated and stabilized with QCS under ultrasonication. The strong coordination between QCS and MoS₂ as well as the electrostatic attraction between QCS and cellulose nanofiber (CNF) helped to fabricate the MoS₂@QCS/CNF composite paper. The MoS₂@QCS/CNF composite paper exhibited excellent photothermal and photodynamic activity, achieving over 99.9% antibacterial efficacy against both E. coli and S. aureus, respectively. The hyperthermia induced by MoS₂ accelerated the glutathione (GSH) consumption and the reactive oxygen species (ROS)-independent oxidative stress destroyed the bacteria membranes integrity, synergistically leading to the malondialdehyde (MDA) oxidation and protein leakage to inhibit the bacteria growth. Importantly, the self-assembled fibrous network incorporating with the photo-stable antibacterial MoS₂ enabled the flexible composite paper with excellent mechanical strength and recyclability for long-term antimicrobial, possessing over 99.9% inhibition even after five cycles. No cell cytotoxicity was observed for the MoS₂@QCS/CNF composite paper, suggesting the potential of composite paper for bacterial infection control.

An Overview of the Importance of Transition-Metal Nanoparticles in Cancer Research

Several authorities have implied that nanotechnology has a significant future in the development of advanced cancer therapies. Nanotechnology makes it possible to simultaneously administer drug combinations and engage the immune system to fight cancer. Nanoparticles can locate metastases in different organs and deliver medications to them. Using them allows for the effective reduction of tumors with minimal toxicity to healthy tissue. Transition-metal nanoparticles, through Fenton-type or Haber-Weiss-type reactions, generate reactive oxygen species. Through oxidative stress, the particles induce cell death via different pathways. The main limitation of the particles is their toxicity. Certain factors can control toxicity, such as route of administration, size, aggregation state, surface functionalization, or oxidation state. In this review, we attempt to discuss the effects and toxicity of transition-metal nanoparticles.

Chemical Modification of Chitosan for Developing Cancer Nanotheranostics

Cancer is a worldwide public health issue that has not been conquered. Theranostics, the combination of a therapeutic drug and imaging agent in one formulation using nanomaterials, has been developed to better cure cancer in recent years. Although diverse biomaterials have been applied in cancer theranostics, chitosan (CS), a natural polysaccharide bearing easy modification sites with excellent biocompatibility and biodegradability, shows great potential for developing cancer nanotheranostics. In this review, we seek to describe the chemical functionalities of CS used in cancer theranostics and their synthesis methods. We also present recent discoveries and research progresses on how the CS functionalization could improve the delivery efficiency of CS-based nanotheranostics. Finally, we report several case studies about the application of CS-based nanotheranostics. This paper focuses on the strategies to construct CS-based theranostics systems via chemical routes and highlights their applications in cancer treatment, which can provide useful references for further studies.

Engineering of bioactive metal sulfide nanomaterials for cancer therapy

Metal sulfide nanomaterials (MeSNs) are a novel class of metal-containing nanomaterials composed of metal ions and sulfur compounds. During the past decade, scientists found that the MeSNs engineered by specific approaches not only had high biocompatibility but also exhibited unique physicochemical properties for cancer therapy, such as Fenton catalysis, light conversion, radiation enhancement, and immune activation. To clarify the development and promote the clinical transformation of MeSNs, the first section of this paper describes the appropriate fabrication approaches of MeSNs for medical science and analyzes the features and limitations of each approach. Secondly, we sort out the mechanisms of functional MeSNs in cancer therapy, including drug delivery, phototherapy, radiotherapy, chemodynamic therapy, gas therapy, and immunotherapy. It is worth noting that the intact MeSNs and the degradation products of MeSNs can exert different types of anti-tumor activities. Thus, MeSNs usually exhibit synergistic antitumor properties. Finally, future expectations and challenges of MeSNs in the research of translational medicine are spotlighted.

A new pH/NIR responsive theranostic agent for magnetic resonance imaging guided synergistic therapy

New nano-reagents with diagnostic imaging and therapeutic functions are very important for precision medicine against cancer. In this work, a new nanotheraontic agent for magnetic resonance imaging (MRI) guided combined photothermal therapy (PTT) and chemotherapy was constructed based on polydopamine (PDA) functionalized copper ferrite nanospheres (PDA@CFNs). The high relaxivity makes it possible for PDA@CFNs to become a promising MRI contrast agent, providing necessary and exhaustive information for tumor diagnosis. In addition, because both CFNs and PDA have strong near-infrared (NIR) absorption, PDA@CFNs exhibit excellent photothermal performance. Highly effective tumor ablation is achieved in a mouse model through PTT and pH/NIR triggered on-demand chemotherapy. These findings reveal that constructing smart pH/NIR responsive multifunctional theranostic agents is a feasible strategy for precision cancer therapy.

Agricultural and Biomedical Applications of Chitosan-Based Nanomaterials

Chitosan has emerged as a biodegradable, nontoxic polymer with multiple beneficial applications in the agricultural and biomedical sectors. As nanotechnology has evolved as a promising field, researchers have incorporated chitosan-based nanomaterials in a variety of products to enhance their efficacy and biocompatibility. Moreover, due to its inherent antimicrobial and chelating properties, and the availability of modifiable functional groups, chitosan nanoparticles were also directly used in a variety of applications. In this review, the use of chitosan-based nanomaterials in agricultural and biomedical fields related to the management of abiotic stress in plants, water availability for crops, controlling foodborne pathogens, and cancer photothermal therapy is discussed, with some insights into the possible mechanisms of action. Additionally, the toxicity arising from the accumulation of these nanomaterials in biological systems and future research avenues that had gained limited attention from the scientific community are discussed here. Overall, chitosan-based nanomaterials show promising characteristics for sustainable agricultural practices and effective healthcare in an eco-friendly manner.

Chitosan Derivatives and Their Application in Biomedicine

Chitosan is a product of the deacetylation of chitin, which is widely found in nature. Chitosan is insoluble in water and most organic solvents, which seriously limits both its application scope and applicable fields. However, chitosan contains active functional groups that are liable to chemical reactions; thus, chitosan derivatives can be obtained through the chemical modification of chitosan. The modification of chitosan has been an important aspect of chitosan research, showing a better solubility, pH-sensitive targeting, an increased number of delivery systems, etc. This review summarizes the modification of chitosan by acylation, carboxylation, alkylation, and quaternization in order to improve the water solubility, pH sensitivity, and the targeting of chitosan derivatives. The applications of chitosan derivatives in the antibacterial, sustained slowly release, targeting, and delivery system fields are also described. Chitosan derivatives will have a large impact and show potential in biomedicine for the development of drugs in future.

Recent advance in delivery system and tissue engineering applications of chondroitin sulfate

Chondroitin sulfate (CS) is a naturally derived bioactive macromolecule and the major component of extracellular matrix (ECM), which widely distributed in various organisms and has attracted much attention due to their significant bioactivities. It is regarded as a favorable biomaterial that has been applied extensively in field of drug delivery and tissue engineering due to its property of non-poisonous, biodegradation, biocompatible and as a major component of ECM. The present article reviews the structure and bioactivities of CS, from the preparation to structure analysis, and emphatically focuses on the biomaterial exertion in delivery system and tissue engineering. At the same time, the present application status and prospect of CS are analyzed and the biomaterial exertion of CS in delivery system and various tissue engineering are also comparatively discussed in view of biomaterial development.

Green synthesis of quaternized chitosan/silver nanocomposites for targeting mycobacterium tuberculosis and lung carcinoma cells (A-549)

Lung cancer (LC) is the most-deadly type of cancer representing a major public health problem worldwide. Tuberculosis TB is another infectious disease influencing lungs that causes death especially in developing countries. The present study is the first to report antimycobacterial activity of TMC/Ag nanocomposite. It aims to solve the case of lung cancer and its most associative pathogen. The current study reports one pot green biosynthesis of silver nanocomposite in presence of biodegradable biopolymer (N,N,N-trimethyl chitosan chloride, TMC) as both reducing and stabilizing agent. The structure of TMC/Ag nanocomposite was characterized with different analysis tools including TEM, XRD and UV-vis spectrophotometer techniques. TEM images showed that Ag nanoparticles were well distributed spheres and their diameter ranged from 11 to17.5 nm. While, XRD pattern of TMC/Ag nanocomposite showed diffraction peaks related to the crystalline nature of Ag nanoparticles. In addition, UV-vis spectrum revealed a broad absorption peak at 400 nm attributing to the surface Plasmon resonance (SPR) of Ag. TMC/Ag nanocomposite exhibited a promising in vitro antimycobacterial activity with MIC of 1.95 μg/mL. On the other hand, The antitumor activity results of nanocomposites against both lung carcinoma cells (A-549) and normal lung cells (WI 38) revealed that nanocomposite cytotoxicity against A-549 cells with IC₅₀ of 12.3 μg/mL, whereas the IC₅₀ value against normal WI 38 cells was 357.2 μg/mL.

CuS@Corn Stalk/Chitin Composite Hydrogel for Photodegradation and Antibacterial

Copper sulfide nanoparticles (CuS NPs) have recently attracted extensive attention in various fields due to their excellent optical and electrical properties. However, CuS NPs are easy to agglomerate in their preparation on account of the high surface activity. In this study, uniform dispersion of CuS NPs were fabricated with corn stalk as a template and stabilizer, further CuS@corn stalk/chitin composite hydrogel was obtained by crosslinking with chitin. The results reveal that the CuS NPs were evenly dispersed into the composite hydrogels with a three-dimensional network structure, which were verified by the UV-vis spectrum, XRD, FT-IR spectra and SEM. In addition, the as-prepared composite hydrogel with the traits of peroxidase-like activity can convert H₂O₂ into an extremely oxidative and toxic ·OH, which manifested good effects for photodegradation of RhB and antibacterial against Escherichia coli and Staphylococcus aureus. Hence, the composite hydrogels could be used for photocatalytic treatment and sterilization of wastewater, which provides a new idea for the functional application of CuS NPs.

Chitosan capped copper oxide/copper nanoparticles encapsulated microbial resistant nanocomposite films

Chitosan (CH) capped inorganic nanomaterials have been considered as significant antibacterial materials in the clinical field. This work shows the synthesis of two new different antibacterial composite films as a result of the incorporation of CH capped copper oxide (CHCuO) and copper (CHCu) nanoparticles (NPs). Here, CHCuO and CHCu NPs were achieved by a facile chemical reduction of Cu²⁺ ions using sodium hydroxide and ascorbic acid. TEM analysis revealed the morphology as rod-type nanoflakes for CHCuO and a spherical shape for CHCu NPs with ~7 ± 2 nm size. Antimicrobial activity of the developed materials was studied by the inhibition zone method, against both gram-negative and gram-positive bacteria. The antimicrobial activity revealed that the CHCuO NPs and CHCuO-CH film showed a higher inhibition zone than the other nanomaterials. The results suggested that the synthesized materials can be used in wound dressing applications.