Nano-enabled strategies to combat methicillin-resistant Staphylococcus aureus

Kombo knife combined with sorafenib in liver cancer treatment: Efficacy and safety under immune function influence

BACKGROUND

In the quest to manage hepatocellular carcinoma (HCC), the focus has shifted to a more holistic approach encompassing both data analytics and innovative treatments. Analyzing rich data resources, such as the cancer genome atlas (TCGA), and examining progressive therapies can potentially reshape the trajectory of HCC treatment.

AIM

To elucidate the immunological genes and the underlying mechanism of the combined Kombo knife and sorafenib regimen for HCC by analyzing data from TCGA and machine learning data.

METHODS

Immune attributes were evaluated via TCGA's postablation HCC RNA sequencing data. Using weighted gene coexpression network analysis and machine learning, we identified genes with high prognostic value. The therapeutic landscape and safety metrics of the integrated treatment were critically evaluated across cellular and animal models.

RESULTS

Immune genes–specifically, peptidylprolyl isomerase A and solute carrier family 29 member 3–emerged as significant prognostic markers. Enhanced therapeutic outcomes, such as prolonged progression-free survival and an elevated overall response rate, characterize the combined approach, with peripheral blood mononuclear cells displaying potent effects on HCC dynamics.

CONCLUSION

The combination of Kombo knife with sorafenib is an innovative HCC treatment modality anchored in immune-centric strategies.

Cytotoxicity and Biological Activities of Geopopolis Extract from the Stingless bee (Melipona scutellaris) in Isolates of Staphylococcus aureus

Geopropolis resins are produced by stingless bees (Meliponinae), developed from the collection of resinous materials, waxes and exudates, from the flora of the region where stingless bees are present, in addition to the addition of clay or earth in its composition. Several biological activities are attributed to Ethanol Extracts of Geopropolis (EEGP). The bioactive properties are associated with the complex chemical composition that the samples have. This work aims to evaluate the biological activities of the EEGP, in order to contribute with a natural therapeutic alternative, to face infections, mainly those caused by resistant strains of Staphylococcus aureus. The EEGP MIC tests showed antibacterial activity against two strains of S. aureus, both at concentrations of 550 μg/mL. The MBC performed with the inhibition values showed that the EEGP has bacteriostatic activity in both strains. Biofilm inhibition rates exhibited an average value greater than 65 % at the highest concentration. The EEGP antioxidant potential test showed good antioxidant activity (IC50) of 11.05±1.55 μg/mL. In the cytotoxicity test against HaCat cells, after 24 hours, EEGP induced cell viability at the three tested concentrations (550 μg/mL: 81.68±3.79 %; 1100 μg/mL: 67.10±3.76 %; 2200 μg/mL: 67.40±1.86 %). In view of the above, the safe use of EEGP from the brazilian northeast could be proven by the cytotoxicity test, and its use as an antioxidant and antibacterial agent has proven to be effective, as an alternative in combating oxidative stress and microorganisms such as S. aureus, which, through the spread and ongoing evolution of drug resistance, generates an active search for effective solutions.

Highly efficient aramid fiber supported polypropylene membranes modified with reduced graphene oxide based metallic nanocomposites: antimicrobial and antiviral capabilities

Polypropylene hybrid polymeric membranes with aramid support have been fabricated using Thermally Induced Phase Separation (TIPS). Different modifying materials, such as metallic nanoparticles and reduced graphene oxide (rGO), improve the properties of these membranes. The nanomaterials and the fabricated membranes have been characterized with FTIR spectrometer, SEM and UV-Vis Spectrophotometer. Following that, the disinfection capabilities of the fabricated hybrid membranes were investigated. The antibacterial capability of the membranes is established through the testing of the membranes against bacterial strains S. aureus and E. coli, whereas the antiviral evaluation of the membranes was made against H9N2 and IBV strains. This research aims to develop advanced hybrid membranes that effectively disinfect water by incorporating novel nanomaterials and optimizing fabrication techniques.

Staphylococcus aureus epidemiology, pathophysiology, clinical manifestations and application of nano-therapeutics as a promising approach to combat methicillin resistant Staphylococcus aureus

Staphylococcus aureus is a Gram-positive bacterium and one of the most prevalent infectious disease-related causes of morbidity and mortality in adults. This pathogen can trigger a broad spectrum of diseases, from sepsis and pneumonia to severe skin infections that can be fatal. In this review, we will provide an overview of S. aureus and discuss the extensive literature on epidemiology, transmission, genetic diversity, evolution and antibiotic resistance strains, particularly methicillin resistant S. aureus (MRSA). While many different virulence factors that S. aureus produces have been investigated as therapeutic targets, this review examines recent nanotechnology approaches, which employ materials with atomic or molecular dimensions and are being used to diagnose, treat, or eliminate the activity of S. aureus. Finally, having a deeper understanding and clearer grasp of the roles and contributions of S. aureus determinants, antibiotic resistance, and nanotechnology will aid us in developing anti-virulence strategies to combat the growing scarcity of effective antibiotics against S. aureus.

The Antimicrobial Potency of Mesoporous Silica Nanoparticles Loaded with Melissa officinalis Extract

Melissa officinalis is an important medicinal plant that is used and studied intensively due to its numerous pharmacological effects. This plant has numerous active compounds with biomedical potential; some are volatile, while others are sensitive to heat or oxygen. Therefore, to increase stability and prolong biological activities, the natural extract can be loaded into various nanostructured systems. In this study, different loading systems were obtained from mesoporous silica, like Mobile Composition of Matter family (MCM) with a hexagonal (MCM-41) or cubic (MCM-48) pore structure, simple or functionalized with amino groups (using 3-aminopropyl) such as triethoxysilane (APTES). Thus, the four materials were characterized from morphological and structural points of view by scanning electron microscopy, a BET analysis with adsorption-desorption isotherms, Fourier-transform infrared spectroscopy (FTIR) and a thermogravimetric analysis coupled with differential scanning calorimetry. Natural extract from Melissa officinalis was concentrated and analyzed by High-Performance Liquid Chromatography to identify the polyphenolic compounds. The obtained materials were tested against Gram-negative bacteria and yeasts and against both reference strains and clinical strains belonging to Gram-positive bacteria that were previously isolated from intra-hospital infections. The highest antimicrobial efficiency was found against Gram-positive and fungal strains. Good activity was also recorded against methicillin-resistant S. aureus, the Melissa officinalis extract inhibiting the production of various virulence factors.

Azadirachta indica (AI)leaf extract coated ZnO-AInanocore-shell particles for enhanced antibacterial activity against methicillin-resistantStaphylococcus aureus(MRSA)

With the rise in microbial resistance to traditional antibiotics and disinfectants, there is a pressing need for the development of novel and effective antibacterial agents. Two major approaches being adopted worldwide to overcome antimicrobial resistance are the use of plant leaf extracts and metallic nanoparticles (NPs). However, there are no reports on the antibacterial potential of NPs coated with plant extracts, which may lead to novel ways of treating infections. This study presents an innovative approach to engineer antibacterial NPs by leveraging the inherent antibacterial properties of zinc oxide NPs (ZnO NPs) in combination withAzadirachta indica(AI) leaf extract, resulting in enhanced antibacterial efficacy. ZnO NPs were synthesised by the precipitation method and subsequently coated withAIleaf extract to produce ZnO-AInanocore-shell structures. The structural and morphological characteristics of the bare and leaf extract coated ZnO NPs were analysed by x-ray diffraction and field emission scanning electron microscopy, respectively. The presence of anAIleaf extract coating on ZnO NPs and subsequent formation of ZnO-AInanocore-shell structures was verified through Fourier transform infrared spectroscopy and photoluminescence techniques. The antibacterial efficacy of both ZnO NPs and ZnO-AInanocore-shell particles was evaluated against methicillin-resistantStaphylococcus aureususing a zone of inhibition assay. The results showed an NP concentration-dependent increase in the diameter of the inhibition zone, with ZnO-AInanocore-shell particles exhibiting superior antibacterial properties, owing to the combined effect of ZnO NPs and the poly phenols present inAIleaf extract. These findings suggest that ZnO-AInanocore-shell structures hold promise for the development of novel antibacterial creams and hydrogels for various biomedical applications.

Fighting Methicillin-Resistant Staphylococcus aureus with Targeted Nanoparticles

Antimicrobial resistance (AMR) is considered one of the greatest threats to global health. Methicillin-resistant Staphylococcus aureus (MRSA) remains at the core of this threat, accounting for about 90% of S. aureus infections widespread in the community and hospital settings. In recent years, the use of nanoparticles (NPs) has emerged as a promising strategy to treat MRSA infections. NPs can act directly as antibacterial agents via antibiotic-independent activity and/or serve as drug delivery systems (DDSs), releasing loaded antibiotics. Nonetheless, directing NPs to the infection site is fundamental for effective MRSA treatment so that highly concentrated therapeutic agents are delivered to the infection site while directly reducing the toxicity to healthy human cells. This leads to decreased AMR emergence and less disturbance of the individual's healthy microbiota. Hence, this review compiles and discusses the scientific evidence related to targeted NPs developed for MRSA treatment.

Development and Evaluation of Novel Encapsulated Isoeugenol-Liposomal Gel Carrier System for Methicillin-Resistant Staphylococcus aureus

In recent years, methicillin-resistant Staphylococcus aureus (MRSA) bacteria have seriously threatened the health and safety of the world’s population. This challenge demands the development of alternative therapies based on plant origin. This molecular docking study ascertained the orientation and intermolecular interactions of isoeugenol within penicillin-binding protein 2a. In this present work, isoeugenol as an anti-MRSA therapy was selected by encapsulating it into a liposomal carrier system. After encapsulation into the liposomal carrier, it was evaluated for encapsulation efficiency (%), particle size, zeta potential, and morphology. The percentage entrapment efficiency (% EE) was observed to be 57.8 ± 2.89% with a particle size of 143.31 ± 7.165 nm, a zeta potential of (−)25 mV, and morphology was found to be spherical and smooth. After this evaluation, it was incorporated into a 0.5% Carbopol gel for a smooth and uniform distribution on the skin. Notably, the isoeugenol-liposomal gel was smooth on the surface with a pH of 6.4, suitable viscosity, and spreadability. Interestingly, the developed isoeugenol-liposomal gel was safe for human use, with more than 80% cell viability. The in vitro drug release study shows promising results with 75.95 ± 3.79% of drug release after 24 h. The minimum inhibitory concentration (MIC) was 8.236 µg/mL. Based on this, it can be concluded that encapsulating isoeugenol into the liposomal gel is a potential carrier for MRSA treatment.

Caraway Nanoemulsion Gel: A Potential Antibacterial Treatment against Escherichia coli and Staphylococcus aureus

Novel antibiotics are needed due to the rise of antibiotic-resistant pathogens. Traditional antibiotics are ineffective due to antibiotic-resistant microorganisms, and finding alternative therapies is expensive. Hence, plant-derived caraway (Carum carvi) essential oils and antibacterial compounds have been selected as alternatives. In this, caraway essential oil as an antibacterial treatment was investigated using a nanoemulsion gel. Using the emulsification technique, a nanoemulsion gel was developed and characterized in terms of particle size, polydispersity index, pH, and viscosity. The results showed that the nanoemulsion had a mean particle size of 137 nm and an encapsulation efficiency of 92%. Afterward, the nanoemulsion gel was incorporated into the carbopol gel and was found to be transparent and uniform. The gel had in vitro cell viability and antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The gel safely delivered a transdermal drug with a cell survival rate of over 90%. With a minimal inhibitor concentration (MIC) of 0.78 mg/mL and 0.78 mg/mL, respectively, the gel demonstrated substantial inhibition for E. coli and S. aureus. Lastly, the study demonstrated that caraway essential oil nanoemulsion gels can be efficient in treating E. coli and S. aureus, laying the groundwork for the use of caraway essential oil as an alternative to synthetic antibiotics in the treatment of bacterial infections.

Tailored anti-biofilm activity - Liposomal delivery for mimic of small antimicrobial peptide

The eradication of bacteria embedded in biofilms is among the most challenging obstacles in the management of chronic wounds. These biofilms are found in most chronic wounds; moreover, the biofilm-embedded bacteria are considerably less susceptible to conventional antimicrobial treatment than the planktonic bacteria. Antimicrobial peptides and their mimics are considered attractive candidates in the pursuit of novel therapeutic options for the treatment of chronic wounds and general bacterial eradication. However, some limitations linked to these membrane-active antimicrobials are making their clinical use challenging. Novel innovative delivery systems addressing these limitations represent a smart solution. We hypothesized that incorporation of a novel synthetic mimic of an antimicrobial peptide in liposomes could improve its anti-biofilm effect as well as the anti-inflammatory activity. The small synthetic mimic of an antimicrobial peptide, 7e-SMAMP, was incorporated into liposomes (~280 nm) tailored for skin wounds and evaluated for its potential activity against both biofilm formation and eradication of pre-formed biofilms. The 7e-SMAMP-liposomes significantly lowered inflammatory response in murine macrophages (~30 % reduction) without affecting the viability of macrophages or keratinocytes. Importantly, the 7e-SMAMP-liposomes completely eradicated biofilms produced by Staphylococcus aureus and Escherichia coli above concentrations of 6.25 μg/mL, whereas in Pseudomonas aeruginosa the eradication reached 75 % at the same concentration. Incorporation of 7e-SMAMP in liposomes improved both the inhibition of biofilm formation as well as biofilm eradication in vitro, as compared to non-formulated antimicrobial, therefore confirming its potential as a novel therapeutic option for bacteria-infected chronic wounds.

Formulation, In Vitro and In Silico Evaluations of Anise (Pimpinella anisum L.) Essential Oil Emulgel with Improved Antimicrobial Effects

Over the past decade, researchers have made several efforts to develop gel-based formulations that provide an alternative to traditional hydrogels and emulgel. Due to its excellent antibacterial properties, anise, the main constituent of Pimpinella anisum L., widely used in pharmaceuticals, was selected as the active ingredient in this study. Since many bacteria have developed considerable antibiotic resistance, this research aimed to develop an herbal emulgel for treating skin infections caused by bacteria. Given these obstacles, we developed and evaluated a new, cost-effective topical emulgel solution containing anise essential oil against Escherichia coli (E. coli). Anise-based emulgels, potential drug delivery platforms, have been evaluated for various parameters, including physical properties, viscosity, pH, rheology, encapsulation efficiency, and in vitro release research. The AEOs emulgel demonstrated remarkable colloidal stability, with a zeta potential of 29 mV, a size of 149.05 nm, and considerable polydispersity. The efficacy of anise-loaded emulgels as antibacterial formulations was evaluated in vitro. E. coli was used as a model microbial organism for the antibacterial study. Human keratinocytes (HaCaT) were used to examine the biocompatibility of the emulgel. Molecular docking revealed that the essential oil components of Pimpinella anisum L. possess a high affinity for the bacterial adhesin protein FimH of E. coli. These findings indicate that the developed AEOs have the potential to be analyzed using E. coli as a model organism.

Recent advances in multifunctional dendrimer-based nanoprobes for breast cancer theranostics

Breast cancer (BC) undoubtedly is one of the most common type of cancers amongst women, which causes about 5 million deaths annually. The treatments and diagnostic therapy choices currently available for Breast Cancer is very much limited . Advancements in novel nanocarrier could be a promising strategy for diagnosis and treatments of this deadly disease. Dendrimer nanoformulation could be functionalized and explored for efficient targeting of overexpressed receptors on Breast Cancer cells to achieve targeted drug delivery, for diagnostics and to overcome the resistance of the cells towards particular chemotherapeutic. Additionally, the dendrimer have shown promising potential in the improvement of therapeutic value for Breast Cancer therapy by achieving synergistic co-delivery of chemotherapeutics and genetic materials for multidirectional treatment. In this review, we have highlighted the application of dendrimer as novel multifunctional nanoplatforms for the treatment and diagnosis of Breast Cancer.

An insight on topically applied formulations for management of various skin disorders

Various types of skin disorders across each age group and in each part of geographical world are very dreadful. Despite not being fatal each time they are always of social and mental concern for suffering individuals, causing complications in millions of patients every day and require comparatively longer duration of treatment. Off late, various topical/transdermal formulations have been widely explored for the treatment of various skin ailments. The efficiency of topical therapy depends on various physiochemical properties of drugs like particle size, particle size distribution, partition coefficient, viscosity of dosage form, skin permeability, skin condition and the site of application. Therefore, in plenty of examples, long-acting topical formulations have shown to be markedly excellent in comparison to conventional dosage forms. The major advantages of topical formulations accrue from their demonstrated ability: (i) Reduced serious side effects that may occur due to undesirably higher systemic absorption of drug. (ii) Enhancement of drug accumulation at the desired site. (iii) Easy incorporation of enormous range of hydrophilic and hydrophobic drugs and (iv) Reduced risk of dose dumping and comparatively easy termination of drug release. The prospective applications of topically applied formulations and the deposition of pharmaceuticals into the skin are examined.

Herbal Fennel Essential Oil Nanogel: Formulation, Characterization and Antibacterial Activity against Staphylococcus aureus

Antimicrobial resistance (AMR) is one of the greatest threats to humanity in the world. Antibiotic-resistant bacteria spread easily in communities and hospitals. Staphylococcus aureus (S. aureus) is a serious human infectious agent with threatening broad-spectrum resistance to many commonly used antibiotics. To prevent the spread of pathogenic microorganisms, alternative strategies based on nature have been developed. Essential oils (EOs) are derived from numerous plant parts and have been described as antibacterial agents against S. aureus. Fennel essential oils were selected as antibacterial agents encapsulated in nanoparticles of polylactic acid and glycolic acid (PLGA). The optimum size of the formulation after loading with the active ingredient was 123.19 ± 6.1595 nm with a zeta potential of 0.051 ± 0.002 (23 ± 1.15 mV). The results of the encapsulation efficiency analysis showed high encapsulation of EOs, i.e., 66.4 ± 3.127. To obtain promising carrier materials for the delivery of fennel EOs, they were incorporated in the form of nanogels. The newly developed fennel oils in PLGANPs nanogels have good drug release and MIC against S. aureus. These results indicate the potential of this novel delivery system for antimicrobial therapy.

Site-Specific Evaluation of Bioactive Coumarin-Loaded Dendrimer G4 Nanoparticles against Methicillin Resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is a foremost treatment challenge in today's clinical practice. Natural coumarins contain a variety of bioactivities and have the ability to alter resistance in several ways. In developing effective drug delivery methods, the goal is to maximize biocompatibility while minimizing toxicity. With this in mind, this work investigated the site-specific potential of dendrimer G4 poloxamer nanoparticles loaded with bioactive coumarin. The goal of the current work is to deliver a complete evaluation of dendrimer G4 poloxamer nanoparticles against MRSA. Coumarin-loaded dendrimer G4 poloxamer nanoparticles were thoroughly investigated and characterized using various techniques, including particle size, shape, entrapment efficiency, in vitro drug release, hemolysis assay, cytotoxicity, antibacterial activity, and bactericidal kinetics. Studies showed that the newly developed dendrimer G4 poloxamer nanoparticles exhibited significantly lower levels of hemolysis and cytotoxicity. The results showed that the in vitro drug release of coumarin from dendrimer G4 poloxamer nanoparticles was slower compared to coumarin in its free form. This innovative therapeutic delivery technology may enhance the defense of coumarin against MRSA.

Coumarin-Encapsulated Solid Lipid Nanoparticles as an Effective Therapy against Methicillin-Resistant Staphylococcus aureus

Bacterial infections caused by antibiotic-resistant pathogens are a significant public health problem. This is because the transmission of infectious diseases is shifting, and new antibiotic-resistant strains of bacteria are emerging. The development of biofilms that are resistant to antibiotics poses another hurdle to drugs and treatment alternatives. Therefore, there is an urgent need to develop innovative strategies to effectively eliminate antibiotic-resistant microorganisms effectively. Natural coumarins have broad spectrum bioactivity and the potential for lower resistance. Coumarin is a secondary metabolite found in certain plants, fungi, and bacteria. It is highly effective against methicillin-resistant Staphylococcus aureus (MRSA). Therefore, coumarin can be used as an alternative to combat MRSA. However, most antibacterial agents lack selective targeting of pathological sites, limiting the efficacy of their antibacterial activity. Efficient MRSA treatments can be achieved through nanoparticle (NPs)-based targeted therapies. To address this challenge, a novel coumarin-loaded solid lipid nanocarrier for MRSA was developed to overcome this challenge. The developed systems exhibited a particle size of 138.5 ± 76.06 nm and a polydispersity index (PDI) of 0.245 ± 0.00. The zeta potential of coumarin-loaded SLNs was reported to be −22.2 ± 8.15 mV with a spherical shape. The encapsulation efficiency of coumarin was reported to be 63.09 ± 3.46% in the final formulation. The developed formulation was biocompatible with a minimum inhibitory concentration (MIC) of 1.08 µg/mL. This study suggests that coumarin-loaded SLNs can effectively treat MRSA infections.

Logic-Based Diagnostic and Therapeutic Nanoplatform with Infection and Inflammation Monitoring and Microenvironmental Regulation Accelerating Wound Repair

Infectious cutaneous wounds are a thorny clinical problem. The microenvironment of the infectious wound is complicated and changes at different healing stages. Traditional treatments either have a single effect such as anti-inflammation, antibacteria, or angiogenesis or a simple mixture of several functions. They fail to deal with the change of the physiological healing process, leading to unsatisfactory outcomes. Herein, we have designed a logic-based smart nanoplatform (named as ZEM), aiming to self-monitor the wound microenvironment and accordingly react to the changes of the healing process, fitting multiple needs of physiological repair at different stages. ZEM was synthesized using zeolitic imidazolate framework-8 (ZIF-8) coated with an epigallocatechin gallate (EGCG)/Mg²⁺ complex. We characterized ZEM in the aspects of morphology, physical and chemical properties, and ion release pattern. At the initial stage, ZEM sensed the weakly acidic environment and responsively released a large number of zinc ions to eliminate bacterial infection. Then came the second inflammation stage, where ZEM responded to the oxidative stress of the local wound area with EGCG absorbing excessive reactive oxygen species (ROS), contributing to the downregulation of intracellular ROS. Meanwhile, local inflammation was alleviated by reducing the expression of proinflammatory M1 phenotype factors (IL-6, TNF-α, and IL-1β). Since the balance of local ROS had been achieved, the resulting disintegration of the EGCG/Mg²⁺ complex gave rise to the sustainable release of Mg²⁺ at the proliferation stage, promoting vascularized healing. In vivo animal experiments further proved the diagnostic and therapeutic functions of ZEM. All these results demonstrated that ZEM was a promising treatment strategy in soft tissue engineering.

Antimicrobial Peptide-Loaded Gelatinase-Responsive Photothermal Nanogel for the Treatment of Staphylococcus aureus-Infected Wounds

As the most common pathogen of community and nosocomial infection, the resistance of Staphylococcus aureus (S. aureus) to traditional antibiotics is still increasing with years. Although the potent antibacterial activity of antimicrobial peptides (AMPs) has been widely confirmed, the unpredictable cytotoxicity remains the biggest obstacle to their clinical application. The development of a targeted drug delivery system for S. aureus is a practical strategy to ameliorate the inherent limitations of AMPs. In this work, we constructed an AMP release nanogel (cypate-GNPs@Cy3-AMP, CGCA) of S. aureus infection microenvironment using gelatinase nanoparticles (GNPs) for toxicity control and bacterial clearance. Gelatinase present in the infected site degrades GNPs, thus releasing Cy3-AMP in situ to destroy bacterial cells. Cypate modified on the surface of GNPs supports CGCA to generate localized heat under near-infrared (NIR) laser irradiation, which together with AMPs could cause irreversible physical damage to bacteria. In addition, the encapsulation from GNPs not only effectively limited the toxicity of AMPs but also significantly promoted cell proliferation and migration in vitro. In the mouse infection model, CGCA also exhibited excellent effects of bacterial clearance and wound healing, providing a potential direction for the correct use of AMPs.

Ti3C2Tx MXene loaded with indocyanine green for synergistic photothermal and photodynamic therapy for drug-resistant bacterium

Infections caused by antibiotic-resistant bacteria are a critical threat to human health. Considering the difficulties and time-consuming nature of synthesizing new antibiotics, it is of great significance and importance to develop the antibiotic-independent antibacterial approaches against drug-resistant bacteria. Nanomaterials-based photothermal therapy (PTT) and photodynamic therapy (PDT) have attracted much attention due to their broad-spectrum bactericidal activity, low toxicity, and drug-free feature. In this work, we loaded indocyanine green (ICG) on the Ti₃C₂T_x MXene nanosheets (454 nm) so as to combine the photothermal effect of MXene with the photodynamic effect of ICG. Without near-infrared (NIR) irradiation, MXene (20 μg/mL), ICG (5 μg/mL) or ICG-loaded MXene (ICG-MXene) showed no significant antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Under NIR, however, the viability loss of MRSA remarkably increased to 45% for MXene, 66% for ICG and 100% for ICG-MXene. We further found that the great anti-MRSA activity of ICG-MXene under NIR was attributed to the combination of photothermal effect of MXene (high temperature) and photodynamic effect of ICG (high level of reactive oxygen species). Our findings indicate that MXene can be used as both the photothermal agent and the carrier of photosensitizers to achieve the synergistic PTT/PDT therapy for bacterial infections.

Advances in Nanostructures for Antimicrobial Therapy

Microbial infections caused by a variety of drug-resistant microorganisms are more common, but there are fewer and fewer approved new antimicrobial chemotherapeutics for systemic administration capable of acting against these resistant infectious pathogens. Formulation innovations of existing drugs are gaining prominence, while the application of nanotechnologies is a useful alternative for improving/increasing the effect of existing antimicrobial drugs. Nanomaterials represent one of the possible strategies to address this unfortunate situation. This review aims to summarize the most current results of nanoformulations of antibiotics and antibacterial active nanomaterials. Nanoformulations of antimicrobial peptides, synergistic combinations of antimicrobial-active agents with nitric oxide donors or combinations of small organic molecules or polymers with metals, metal oxides or metalloids are discussed as well. The mechanisms of actions of selected nanoformulations, including systems with magnetic, photothermal or photodynamic effects, are briefly described.

Recent advances in nanocarriers for nutrient delivery

For the past few years, there has been a surge in the use of nutraceuticals. The global nutraceuticals market in 2020 was USD 417.66 billion, and the market value is expected to increase by 8.9% compound annual growth rate from 2020 to 2028. This is because nutraceuticals are used to treat and prevent various diseases such as cancer, skin disorders, gastrointestinal, ophthalmic, diabetes, obesity, and central nervous system-related diseases. Nutritious food provides the required amount of nutrition to the human body through diet, whereas most of the bioactive agents present in the nutrients are highly lipophilic, with low aqueous solubility leading to poor dissolution and oral bioavailability. Also, the nutraceuticals like curcumin, carotenoids, anthocyanins, omega-3 fatty acids, vitamins C, vitamin B12, and quercetin have limitations such as poor solubility, chemical instability, bitter taste, and an unpleasant odor. Additionally, the presence of gastrointestinal (GIT) membrane barriers, varied pH, and reaction with GIT enzymes cause the degradation of some of the nutraceuticals. Nanotechnology-based nutrient delivery systems can be used to improve oral bioavailability by increasing nutraceutical stability in foods and GIT, increasing nutraceutical solubility in intestinal fluids, and decreasing first-pass metabolism in the gut and liver. This article has compiled the properties and applications of various nanocarriers such as polymeric nanoparticles, micelles, liposomes, niosomes, solid lipid nanocarriers, nanostructured lipid carrier, microemulsion, nanoemulsion, dendrimers in organic nanoparticles, and nanocomposites for effective delivery of bioactive molecules.

Gum Acacia Functionalized Colloidal Gold Nanoparticles of Letrozole as Biocompatible Drug Delivery Carrier for Treatment of Breast Cancer

The most prevalent malignancy among postmenopausal women is breast cancer. It is one of the leading causes of cancer-related mortality among women. Letrozole (LTZ) is a clinically approved inhibitor for breast cancer in postmenopausal women. However, due to poor aqueous solubility, non-specific binding, unwanted toxicity, and poor blood circulation hampered its clinical applications. To maximize the pharmacological effects and minimize the side effects, inorganic nanoparticles are a good alternative. Due to excellent biocompatibility and minimum cytotoxicity, gold nanoparticles (AuNPs) offer distinct benefits over other metal nanoparticles. Emerging as attractive components, AuNPs and Gum acacia (GA) have been extensively studied as biologically safe nanomaterials for the treatment of cancers. This study reports the synthesis and characterization of GA stabilized gold nanoparticles (GA-AuNPs) of LTZ for breast cancer treatment. The observed particle size of optimized LTZ @ GA-AuNPs was 81.81 ± 4.24 nm in size, 0.286 ± 0.143 of polydispersity index (PDI) and -14.6 ± -0.73 mV zeta potential. The biologically synthesized LTZ @ GA-AuNPs also demonstrated dose-dependent cytotoxicity against the human breast cancer cell line MCF-7, with an inhibitory concentration (IC50) of 3.217 ± 0.247. We determined the hemolytic properties of the LTZ @ GA-AuNPs to evaluate the interaction between the nanoparticles and blood components. Results showed that there is no interaction between LTZ @ GA-AuNPs and blood. In conclusion, the findings indicate that LTZ @ GA-AuNPs has significant potential as a promising drug delivery carrier for treating breast cancer in postmenopausal women.