Assessing the potential of lignin nanoparticles as drug carrier: Synthesis, cytotoxicity and genotoxicity studies

Investigating the Osteogenic Potential of Bone-Targeted Daidzein Loaded Hydroxyapatite Nanoparticles for Postmenopausal Osteoporosis: Pharmacodynamic, Biochemical, and Genotoxicity Evaluations

Bisphosphonates and Hormone Replacement Therapy are the primary therapeutic interventions for Postmenopausal Osteoporosis (PMO), however, associated repercussions limit their usage. To address this challenge, we hypothesized the codelivery of hydroxyapatite (HAP) with daidzein (DZ) for synergistic treatment of PMO. Propounding this bimodal approach, daidzein-loaded hydroxyapatite nanoparticles (DZHAPNPs) were prepared leveraging the estrogenic properties of DZ while utilizing HAP to facilitate biomineralization. The osteogenic potential of developed nanoparticles was validated through in vitro experiments on MG-63 cells and in vivo studies employing a "4-vinyl cyclohexene diepoxide-induced menopausal-mice model". DZHAPNPs exhibited pronounced pro-osteogenic activity, evidenced by enhanced (155.49%) alkaline phosphatase (ALP) activity in MG-63 cells. Additionally, cellular uptake studies confirmed their internalization and targeted delivery. Following menopause induction and treatment, the mice underwent radiography, histology, micro-computed tomography (micro-CT) analysis, and biochemical evaluations. A significant reduction (p < 0.001) in biomarkers i.e. β-CTx, BALP, and TRAP-5b, post-treatment showed a substantial influence of DZ and DZHAPNPs. Better bone architectural parameters and bone mineral density in micro-CT analysis served as proof of the hypothesis. Also, cellular biocompatibility of nanoparticles was confirmed through genotoxicity tests performed on the Drosophila melanogaster. The noteworthy results of the research substantiated the synergistic influence of DZ and HAPNPs in resilience and bone strength maintenance.

Nanomaterials-Based Drug Delivery Systems for Therapeutic Applications in Osteoporosis

The etiology of osteoporosis is rooted in the disruption of the intricate equilibrium between bone formation and bone resorption processes. Nevertheless, the conventional anti-osteoporotic medications and hormonal therapeutic regimens currently employed in clinical practice are associated with a multitude of adverse effects, thereby constraining their overall therapeutic efficacy and potential. Recently, nanomaterials have emerged as a promising alternative due to their minimal side effects, efficient drug delivery, and ability to enhance bone formation, aiding in restoring bone balance. This review delves into the fundamental principles of bone remodeling and the bone microenvironment, as well as current clinical treatment approaches for osteoporosis. It subsequently explores the research status of nanomaterial-based drug delivery systems for osteoporosis treatment, encompassing inorganic nanomaterials, organic nanomaterials, cell-mimicking carriers and exosomes mimics and emerging therapies targeting the osteoporosis microenvironment. Finally, the review discusses the potential of nanomedicine in treating osteoporosis and outlines the future trajectory of this burgeoning field. The aim is to provide a comprehensive reference for the application of nanomaterial-based drug delivery strategies in osteoporosis therapy, thereby fostering further advancements and innovations in this critical area of medical research.

Adverse Outcome Pathways (AOPs) Oriented Approach to Assess In Vitro Hazard of Silica and Lignin Nanomaterials Derived from Biomass Residues

Bio-based nanomaterials (B-NMs), such as silica oxide (SiO2)- and lignin (Lig)- based nanoparticles (NPs) derived from biomass waste, have gained attention in the last few years in the view of promoting the sustainability principles in several applications. However, scarce data are available about their safety. Thus, a hazard-testing strategy was designed considering as a reference the safe-and-sustainable-by-design (SSbD) framework for chemicals and materials, prioritizing the use of new approach methodologies (NAMs), such as in vitro and adverse outcome pathways (AOPs) approaches, for generating data about the potential hazard of B-NMs. Literature research was performed to identify the adverse outcomes (AOs) related to the selected B-NMs. All the AOPs investigated shared at least oxidative stress, inflammation and cytotoxicity as key events (KEs) that were investigated in lung and immune cells. The tested B-NMs resulted either non-toxic or moderately toxic towards human cells, validating their biocompatibility when compared to reference NMs of similar composition, but not of bio-origin. However, attention should be given to possible AOs deriving after specific functionalization of the B-NMs. Considering the lack of knowledge in this field, the studies performed represent a step forward in the state of the art of the safety assessment of B-NMs.

Lignin nanoparticle-stabilized pickering emulsion: Mechanism, influencing parameter, and emerging application

Pickering emulsions using solid particles as stabilizers have attracted considerable interest due to their unique properties, environmental protection, high stability, and cost-effectiveness. However, the current solid particles used as stabilizers have been unable to meet the demands for sustainable development. Lignin nanoparticles (LNPs) are nanoscale particles derived from lignin, a complex biopolymer found in the cell walls of woods and plants. In recent years, LNPs have been widely used to stabilize Pickering emulsions due to its abundance, nanometer size, large specific surface area, good wettability, non-toxicity, and biodegradability. In this review, we overview the recent advances in the LNP-stabilized Pickering emulsion and their applications in a wide spectrum of emerging fields. The structure, preparation, and safety of LNPs are briefly overviewed. Then, the stabilization mechanism of LNP-stabilized Pickering emulsion is introduced. Next, two types of LNP-stabilized Pickering emulsion (i.e., unmodified and modified LNPs), their influencing factors, and physiochemical properties are comprehensively discussed. The recent advances in the application of LNP-stabilized Pickering emulsions in five areas are subsequently outlined, i.e., i) nanocomposites, ii) two-phase catalysis, iii) biomedicine, iv) daily skincare products, and v) enhanced oil recovery. Finally, the prospects of LNP-stabilized Pickering emulsion in the aforementioned fields are proposed.

Lignin-Based Nanocarrier for Simultaneous Delivery of 131I and SN-38 in the Combined Treatment of Solid Tumors by a Nanobrachytherapy Approach

Background: The rapid rise in cancer incidence significantly augments efforts to improve cancer treatments. A multimodal approach in the nanobrachytherapy of solid tumors is one of the promising methods under investigation. This study presents a novel biocompatible lignin-based nanomaterial, loaded with cytostatic agent SN-38 and radionuclide 131I, for simultaneous radiation and chemotherapy of solid tumors by a nanobrachytherapy approach. Method: Nanoparticles of ~100 nm in size, composed of lignin alone or loaded with 10% (m/m) of SN-38 (SN-38@lignin), were synthesized using a bottom-up approach and characterized. Subsequent radiolabeling of the nanoparticles by 131I produced 131I-lignin and 131I-SN-38@lignin. Their antitumor efficiency was tested against luciferase-expressing 4T1 mouse breast cancer xenografts of ~100 mm3 size on Balb/c mice. Results: An intratumoral injection of 1.85 MBq of 131I-lignin was retained within the tumor and achieved a moderate twofold decrease in tumor size compared to the control group. Injecting SN-38@lignin containing 25 µg of SN-38 decreased tumor size 3.5-fold. The therapy using the same doses of 131I-SN-38@lignin produced the most potent antitumor effect, with tumors being 6-fold smaller and having extensive intratumoral necrosis, all of it without signs of systemic toxicity. Conclusions: These results support the intratumoral delivery of lignin-based nanomaterial carrying radioisotopes and camptothecins for effective multimodal anticancer therapy.

Preparation and Biological Activity of Lignin-Silver Hybrid Nanoparticles

Silver nanoparticles (AgNPs) are excellent antimicrobial agents and promising candidates for preventing or treating bacterial infections caused by antibiotic resistant strains. However, their increasing use in commercial products raises concerns about their environmental impact. In addition, traditional physicochemical approaches often involve harmful agents and excessive energy consumption, resulting in AgNPs with short-term colloidal stability and silver ion leaching. To address these issues, we designed stable hybrid lignin-silver nanoparticles (AgLigNPs) intended to effectively hit bacterial envelopes as a main antimicrobial target. The lignin nanoparticles (LigNPs), serving as a reducing and stabilizing agent for AgNPs, have a median size of 256 nm and a circularity of 0.985. These LigNPs were prepared using the dialysis solvent exchange method, producing spherical particles stable under alkaline conditions and featuring reducing groups oriented toward a wrinkled surface, facilitating AgNPs synthesis and attachment. Maximum accumulation of silver on the LigNP surface was observed at a mass reaction ratio mAg:mLig of 0.25, at pH 11. The AgLigNPs completely inhibited suspension growth and reduced biofilm development by 50% in three tested strains of Pseudomonas aeruginosa at a concentration of 80/9.5 (lignin/silver) mg L-1. Compared to unattached AgNPs, AgLigNPs required two to eight times lower silver concentrations to achieve complete inhibition. Additionally, our silver-containing nanosystems were effective against bacteria at safe concentrations in HEK-293 and HaCaT tissue cultures. Stability experiments revealed that the nanosystems tend to aggregate in media used for bacterial cell cultures but remain stable in media used for tissue cultures. In all tested media, the nanoparticles retained their integrity, and the presence of lignin facilitated the prevention of silver ions from leaching. Overall, our data demonstrate the suitability of AgLigNPs for further valorization in the biomedical sector.

Minimizing food oxidation using aromatic polymer: From lignin into nano-lignin

Food loss and waste caused by oxidation result in environmental and economic losses and health threats. Lignin is an abundant aromatic polymer with varied antioxidant capacity, which can reduce food oxidation caused by radical species exposure. The lignin antioxidant strength can be influenced by source, type, structure, processing, degradation products, chemical modifications, and particle size. Lignin in micro- or nano-particles has high reactivity and is associated with increased surface area to improve antioxidant capacity. Lignin can be used as a food additive to suppress lipid and protein oxidation, although its effect on fruit/vegetable oxidation needs to be discussed. The lignin antioxidant properties are promising to be applied in food industries, such as food additives, animal feed supplements, and antioxidant packaging designs. However, there are challenges and limitations to consider, such as the potential for toxicity reactions in some individuals and the need for further research to understand its effects on different food products fully. As a feed nutrition, lignin can improve meat quality. Meanwhile, loading lignin in the packaging matrix can extend the food shelf life through antioxidant and antimicrobial activities, and UV-block. Lignin also improves packaging properties (conventional and 3D-printing fabrication) to maintain food quality, e.g., changes in mechanical properties, hydrophobicity, water vapor permeability, and other influences. This article reviews lignin's role as a natural antioxidant in the food industry. Future directions and discussions relate to prooxidative mechanisms, toxicity, fruit and vegetable preservation mechanisms, inhibition of protein oxidation, activity to food enzymes (fruit ripening enzyme activators and inhibitors of cellulase and β-glucosidase enzyme), dispersity in packaging matrices, and material diversification for 3D printing.

Exploiting lignin-based nanomaterials for enhanced anticancer therapy: A comprehensive review and future direction

Lignin, a renewable and abundant natural polymer, has emerged as a promising candidate for anticancer therapy due to its unique properties and biocompatibility. This review provides a comprehensive overview of recent advancements in the utilization of lignin-based nanomaterials for enhancing anticancer drug delivery and therapeutic outcomes. A detailed examination of the literature reveals several synthesis methods, including nanoprecipitation, microemulsion, and solvent exchange, which produce lignin nanoparticles with improved drug solubility and bioavailability. The anticancer mechanisms of lignin nanoparticles, such as the generation of reactive oxygen species (ROS), induction of apoptosis, and enhanced cellular uptake, are also explored. Lignin nanoparticles loaded with drugs like curcumin, doxorubicin, camptothecin, and resveratrol have demonstrated the ability to improve drug efficacy, selectively target cancer cells, overcome multidrug resistance, and minimize toxicity in both in vitro and in vivo studies. These nanoparticles have shown significant potential in suppressing tumor growth, inducing cell death through apoptotic pathways, and enhancing the synergistic effects of combination therapies, such as chemo-phototherapy. Future research directions include optimizing lignin nanoparticle formulations for clinical applications, refining targeted delivery mechanisms to cancer cells, and conducting thorough biocompatibility and toxicity assessments. Overall, this review highlights the significant progress made in utilizing lignin-based nanomaterials for cancer therapy and outlines promising areas for further exploration in this rapidly evolving field.

Recovery of green phenolic compounds from lignin-based source: Role of ferulic acid esterase towards waste valorization and bioeconomic perspectives

The production of chemicals/products so far relies on fossil-based resources with the creation of several environmental problems at the global level. In this situation, a sustainable and circular economy model is necessitated to mitigate global environmental issues. Production of biowaste from various processing industries also creates environmental issues which would be valorized for the production of industrially important reactive and bioactive compounds. Lignin acts as a vital part in biowaste composition which can be converted into a wide range of phenolic compounds. The phenolic compounds have attracted much attention, owing to their influence on diverse not only organoleptic parameters, such as taste or color, but also active agents for active packaging systems. Crop residues of varied groups, which are an affluent source of lignocellulosic biomass could serve as a renewable resource for the biosynthesis of ferulic acid (FA). FA is obtained by the FA esterase enzyme action, and it can be further converted into various tail end phenolic flavor green compounds like vanillin, vanillic acid and hydroxycinnamic acid. Lignin being renewable in nature, processing and management of biowastes towards sustainability is the need as far as the global industrial point is concerned. This review explores all the approaches for conversion of lignin into value-added phenolic compounds that could be included to packaging applications. These valorized products can exhibit the antioxidant, antimicrobial, cardioprotective, anti-inflammatory and anticancer properties, and due to these features can emerge to incorporate them into production of functional foods and be utilization of them at active food packaging application. These approaches would be an important step for utilization of the recovered bioactive compounds at the nutraceutical and food industrial sectors.

Lignin-Based Nanoparticles for Combination of Tumor Oxidative Stress Amplification and Reactive Oxygen Species Responsive Drug Release

In this study, maleic anhydride-modified lignin (LG-M), a ROS-cleavable thioketal (TK) bond, and polyethylene glycol (PEG) were used to synthesize a lignin-based copolymer (LG-M(TK)-PEG). Doxorubicin (DOX) was attached to the ROS-cleavable bond in the LG-M(TK)-PEG for the preparation of the ROS-activatable DOX prodrug (LG-M(TK-DOX)-PEG). Nanoparticles (NPs) with a size of 125.7 ± 3.1 nm were prepared by using LG-M(TK-DOX)-PEG, and they exhibited enhanced uptake by cancer cells compared to free DOX. Notably, the presence of lignin in the nanoparticles could boost ROS production in breast cancer 4T1 cells while showing little effect on L929 normal cells. This selective effect facilitated the specific activation of the DOX prodrug in the tumor microenvironment, resulting in the superior tumor inhibitory effects and enhanced biosafety relative to free DOX. This work demonstrates the potential of the LG-M(TK-DOX)-PEG NPs as an efficient drug delivery system for cancer treatment.

Co-production of fermentable sugars and highly active lignin from eucalyptus via a mild preprocessing with diethylene glycol and chromic chloride

Eucalyptus was pretreated with diethylene glycol catalyzed by 0.02 mol/L CrCl3 for 10 min, resulting in 91 % delignification and 98 % cellulose recovery, with trace fermentation inhibitors generated. After the mild pretreatment, the accessibility and affinity of cellulase to eucalyptus was enhanced, especially since enzyme adsorption rate increased by 1.6-fold. Therefore, glucose yield of pretreated eucalyptus was 7.9-fold higher than that of untreated eucalyptus after hydrolyzed 48 h, in which the maximum glucose concentration reached 62 g/L from eucalyptus by adding Tween 80. According to the characterization analysis, the structure of the eucalyptus lignin-carbohydrate complexes structure was destroyed during the pretreatment, while lignin fragments was likely reacted with diethylene glycol to form the stabilized aromatic ethers. Moreover, the extracted Deg-lignin exhibited better performances than commercial alkali lignin such as higher fluorescence intensity, less negative surface charge, and lower particle size. The mild pretreatment method with diethylene glycol and CrCl3 provided a promising approach for co-production of fermentable sugars and high activity lignin from lignocellulosic biomass.

Doxorubicin encapsulated blend of sitagliptin-lignin polymeric drug delivery system for effective combination therapy against cancer

In this research, a sitagliptin-lignin biopolymer (SL) containing zinc selenide quantum dots (ZnSe QDs) and doxorubicin (doxo) was synthesized. The fabricated polymeric drug delivery system was characterized via FTIR, XRD, SEM, TGA, IR, and DSC. SLQD-Doxo exhibited an irregular surface with a 32 nm diameter and well-defined surface chemistry. Drug loading efficiency was assessed at different concentrations, pH levels, time intervals, and temperatures, and drug kinetics were calculated. Maximum drug release was observed at 6 μmol concentration after 24 h, pH of 6.5 and 45 °C. The maximum drug encapsulation efficiency was 81.75 %. SLQD-Doxo demonstrated 24.4 ± 1.04 % anti-inflammatory activity, and the maximum lipoxygenase inhibition in a concentration-dependent manner was 71.45 ± 2.02 %, compared to indomethacin, a standard anticancer drug. The designed system was applied to breast cancer MCF-7 cells to evaluate anticancer activity. Cytotoxicity of SLQD-Doxo resulted in 24.48 ± 1.64 dead cells and 74.39 ± 4.12 viable cells. Lignin's polyphenolic nature resulted in good antioxidant activity of LLQD-Doxo. The combination of SLQD-Doxo was appropriate for drug delivery at high temperatures and acidic pH of tumor cells compared to healthy cells.

Synthesis of novel nonsteroidal anti-inflammatory galloyl β-sitosterol-loaded lignin-capped Ag-based drug

Biocompatible anti-inflammatory lignin-capped Ag (LCAg) nanoparticles (NPs) were synthesized for the delivery of galloyl β-sitosterol (Galloyl-BS). β-Sitosterol (BS) is effective against inflammatory responses, like cancer-induced inflammations. BS was modified via gallic acid esterification to enhance its anti-inflammatory potential. LCAg NPs were synthesized by a green method and loaded with galloyl-BS. For comparison, pure BS was also loaded onto LCAg NPs in a separate assembly. The antioxidant potential of Galloyl-BS was greater (IC50 177 µM) than pure BS. Materials were characterized by FT-IR, SEM, XRD, and Zeta potential. Using UV-Vis spectroscopy, drug release experiments were performed by varying pH, time, concentration, and temperature. Maximum drug release was observed after 18 h at pH 6 and 40 °C. Galloyl-BS showed improved drug loading efficiency, release %age, and antioxidant activity compared to pure BS when loaded onto LCAg NPs. DLCAg exhibited excellent anti-inflammatory activity in rat models. These findings indicate that galloyl-BS (drug)-loaded LCAg (DLCAg) NPs have the potential as an anti-inflammatory agent without any prior release and scavenging in normal cells.

Exploring the potential of lignin nanoparticles in enhancing the mechanical, thermal, and bioactive properties of poly (butylene adipate-co-terephthalate)

The preparation and characterization of lignin nanoparticles (LNPs) were described. LNPs were produced via the precipitation technique. Nanocomposites of LNPs with poly (butylene adipate-co-terephthalate) (PBAT) were prepared by melt mixing with various concentrations up to 6 wt% of LNPs. The assessment of the effects of LNP addition on the mechanical, thermal, morphological, cytotoxicity, antioxidant, antibacterial, and antiviral properties of nanocomposites was carefully performed. The addition of LNPs to PBAT enhances the thermal stability of the nanocomposites. The antioxidant effect of LNPs on PBAT increased with increasing filler content. LNPs showed higher efficiency as antioxidant agents than lignin particles (LP). The tensile modulus increased by 20 % for the nanocomposites with 6 % LNPs in comparison with neat PBAT. The crystallization peak temperature of PBAT was 80 °C, which increased to 104.6 °C with the addition of 6 wt% of LNPs, suggesting their strong nucleation activity. Antibacterial tests demonstrated the bacteriostatic activities of LNP, LP, and nanocomposites. Both LP and LNP showed considerable antiviral activity against herpes simplex virus type 1 and human coronavirus 229e. The antiviral activity of LNP was concentration-dependent. The findings suggest that LNP is a promising bio-additive for PBAT and can enhance its properties for various applications, including food packaging.

In Vivo Toxicological Analysis of the ZnFe2O4@poly(tBGE-alt-PA) Nanocomposite: A Study on Fruit Fly

Recently, the use of hybrid nanomaterials (NMs)/nanocomposites has widely increased for the health, energy, and environment sectors due to their improved physicochemical properties and reduced aggregation behavior. However, prior to their use in such sectors, it is mandatory to study their toxicological behavior in detail. In the present study, a ZnFe2O4@poly(tBGE-alt-PA) nanocomposite is tested to study its toxicological effects on a fruit fly model. This nanocomposite was synthesized earlier by our group and physicochemically characterized using different techniques. In this study, various neurological, developmental, genotoxic, and morphological tests were carried out to investigate the toxic effects of nanocomposite on Drosophila melanogaster. As a result, an abnormal crawling speed of third instar larvae and a change in the climbing behavior of treated flies were observed, suggesting a neurological disorder in the fruit flies. DAPI and DCFH-DA dyes analyzed the abnormalities in the larva's gut of fruit flies. Furthermore, the deformities were also seen in the wings and eyes of the treated flies. These obtained results suggested that the ZnFe2O4@poly(tBGE-alt-PA) nanocomposite is toxic to fruit flies. Moreover, this is essential to analyze the toxicity of this hybrid NM again in a rodent model in the future.

QbD-Assisted Development and Optimization of Doxycycline Hyclate- and Hydroxyapatite-Loaded Nanoparticles for Periodontal Delivery

The current research aims to develop a carrier system for the delivery of a matrix metalloproteinase (MMP) inhibitor along with a bioceramic agent to the periodontal pocket. It is proposed that the present system, if given along with a systemic antibiotic, would be a fruitful approach for periodontitis amelioration. To fulfill the aforementioned objective, a doxycycline hyclate- and hydroxyapatite-adsorbed composite was prepared by a physical adsorption method and successfully loaded inside sodium alginate-chitosan nanoparticles and optimized based on particle size and drug content. Optimized formulation was then subjected to different evaluation parameters like encapsulation efficiency, hydroxyapatite content, ζ potential, surface morphology, in vitro drug release, cell line studies, and stability studies. For the optimized formulation, particle size, polydispersity index (PDI), entrapment efficiency, ζ potential, and drug content were found to be 336.50 nm, 0.23, 41.77%, -13.85 mV, and 14.00%, respectively. The surface morphology of the placebo and adsorbed composite-loaded nanoparticles as observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed the spherical shape and rough surface of the particles. In gingival crevicular fluid (GCF) 7.6, a sustained drug release profile was obtained up to 36 h. In vitro % viability studies performed on murine fibroblast cells (NIH3T3) and human periodontal ligament (hPDL) cell lines confirmed the proliferative nature of the formulation. Also, when subjected to stability studies for 4 weeks, particle size, PDI, and drug content did not vary considerably, thereby ensuring the stable nature of nanoparticles. Henceforth, sodium alginate-chitosan nanoparticles appeared to be a good carrier system for doxycycline hyclate and hydroxyapatite for periodontal therapy. If given along with a system antibiotic, the system will serve as a fruitful tool for infection-mediated periodontal regeneration and healing.

In silico and in vitro assessment of an optimized QbD-guided myoinositol and metformin-loaded mucus-penetrating particle-based gel for the amelioration of PCOS

Polycystic ovarian syndrome (PCOS) is a multi-factorial endocrine disorder affecting women of reproductive age. However, its high prevalence and the unsuccessful translation of conventional modalities have made PCOS a pharmaco-therapeutic challenge. In the present study, we explored bi-formulations (comprising metformin-loaded mucus-penetrating nanoparticles, MTF-MPPs, and myoinositol-loaded mucus-penetrating particles, MI-MPPs) incorporated in a carbomer gel tailored for intravaginal administration. For the development and optimization of the MPPs-gel, a QbD (quality by design) approach was employed, including the initial and final risk assessment, central composite design of experts, and method validation. The optimized MTF-MPPs and MI-MPPs possessed an optimum nanometric particle size (195.0 nm and 178.8 nm, respectively) and a PDI of 0.150 and 0.123, respectively, together with a negligible negative zeta potential (-5.19 mV and -6.19 mV, respectively) through the vaginal mucus. It was observed that the MPPs are small and monodisperse with a neutral surface charge. It was observed that the MPPs-gel formulations released approximately 69.86 ± 4.65% of MTF and 67.14 ± 5.74% of MI within 120 h (5 days), which was observed to be sustained unlike MFT-MI-gel with approximately 94.89 ± 4.17% of MTF and 90.91 ± 15% of MI drugs released within 12 h. The confocal microscopy study of rhodamine-loaded MPPs indicated that they possessed a high fluorescence intensity at a depth of 15 μm, while as the penetration trajectory in the vaginal tissue increased to 35 μm, their intensity was reduced, appearing to be more prominent in the blood vessels. The analyzed data of MPPs-gel suggest that the optimized MPPs-gel formulation has potential to reach the targeted area via the uterovaginal mucosa, which has a wide network of blood vessels. Subsequently, in vivo studies were conducted and the results revealed that the proposed MPPs-gel formulation could regulate the estrous cycle of the reproductive system compared to the conventional formulation. Moreover, the formulation significantly reduced the weight of the ovaries compared to the control and conventional vaginal gel. Biochemical estimation showed improved insulin and sex hormone levels. Thus, the obtained data revealed that the deep penetration and deposition of MTF and MI on the targeted area through intravaginal delivery resulted in better therapeutic effects than the conventional vaginal gel. The obtained results confirmed the amelioration of PCOS upon treatment using the prepared MPPs-gel formulation. According to the relevant evaluation studies, it was concluded that MPPs-gel was retained in the vaginal cavity for systemic effects. Also, the sustained and non-irritating therapeutic effect meets the safety aspects. This work serves as a promising strategy for intravaginal drug delivery.

Antimicrobial Peptide-Inspired Design of Amino-Modified Lignin with Improved Antimicrobial Activities

A major challenge to make use of lignin as an antimicrobial material is the weak antimicrobial activity of industrial lignin. Inspired by the antimicrobial mechanism of actions of antimicrobial peptides, alkyldiamines were employed as lysine mimics for lignin modifications. Accordingly, aminoalkyl-modified lignins with different degrees of substitution of amino groups and different hydrophobicity were synthesized. The chemical structure, properties, and antimicrobial activities of the as-prepared aminoalkyl lignins were thoroughly characterized with state-of-the-art technologies. The results indicated that aminobutyl lignin showed enhanced antimicrobial activity against S. aureus and E. coli and performed even better than copper ions. The antimicrobial mechanism of action of the as-prepared aminobutyl lignin was similar to that of polylysine, which damaged the cell membrane, leading to the leakage of intracellular molecules and death of the cell. This study provides a feasible approach to afford modified lignin with enhanced antimicrobial performance, which would facilitate the high-value valorization of lignin as biological materials.

Carvacrol-Loaded Phytosomes for Enhanced Wound Healing: Molecular Docking, Formulation, DoE-Aided Optimization, and in vitro/in vivo Evaluation

Background

Despite recent advances in wound healing products, phytochemicals have been considered promising and attractive alternatives. Carvacrol (CAR), a natural phenolic compound, has been reported to be effective in wound healing.

Purpose

This work endeavored to develop novel CAR-loaded phytosomes for the enhancement of the wound healing process.

Methods

Molecular docking was performed to compare the affinities of the different types of phospholipids to CAR. Phytosomes were prepared by three methods (thin-film hydration, cosolvency, and salting out) using Lipoid S100 and Phospholipon 90H with three levels of saturation percent (0%, 50%, and 100%), and three levels of phospholipid molar percent (66.67%, 75%, and 80%). The optimization was performed using Design Expert where particle size, polydispersity index, and zeta potential were chosen as dependent variables. The optimized formula (F1) was further investigated regarding entrapment efficiency, TEM, 1H-NMR, FT-IR, DSC, X-RD, in vitro release, ex vivo permeation, and stability. Furthermore, it was incorporated into a hydrogel formulation, and an in vivo study was conducted to investigate the wound-healing properties of F1.

Results

F1 was chosen as the optimized formula prepared via the thin-film hydration method with a saturation percent and a phospholipid molar percent of zero and 66.67, respectively. TEM revealed the spherical shape of phytosomal vesicles with uniform size, while the results of 1H-NMR, FT-IR, DSC, and X-RD confirmed the formation of the phytosomal complex. F1 demonstrated a higher in vitro release and a slower permeation than free CAR. The wound area of F1-treated animals showed a marked reduction associated with a high degree of collagen fiber deposition and enhanced cellular proliferation.

Conclusion

F1 can be considered as a promising remedy for the enhancement of wound healing and hence it would be hoped to undergo further investigation.

Fabrication of carboxymethyl cellulose/hyaluronic acid/polyvinylpyrrolidone composite pastes incorporation of minoxidil-loaded ferulic acid-derived lignin nanoparticles and valproic acid for treatment of androgenetic alopecia

Androgenetic alopecia (AGA) is a transracial and cross-gender disease worldwide with a higher prevalence among young individuals. Traditional oral or subcutaneous injections are often used to treat AGA, however, they may cause severe side-effects and therefore effective treatments for AGA are currently lacking. In this work, to treat AGA, we developed a composite paste system based on minoxidil (MXD)-loaded nanoparticles and valproic acid (VPA) with the assistance of roller-microneedles (roller-MNs). The matrix of composite paste systems is carboxymethyl cellulose (CMC), hyaluronic acid (HA) and polyvinylpyrrolidone (PVP). The roller-MNs can create microchannels in the skin to enhance drug transdermal efficiency. With the combined effects of the stimulation hair follicle (HF) regrowth by upregulating Wnt/beta-catenin of VPA and the mechanical microchannels induced by roller-MNs, the as-prepared composite paste systems successfully boost perifollicular vascularization, and activate hair follicle stem cells, thereby inducing notably faster hair regeneration at a lower administration frequency on AGA mouse model compared with minoxidil. This approach offers several benefits, including the avoidance of efficacy loss due to the liver's first-pass effect associated with oral drug, reduction in the risk of infection from subcutaneous injection, and significant decrease in the side effects of lower-dose MXD.

CD44 mediated colon cancer targeting mutlifaceted lignin nanoparticles: Synthesis, in vitro characterization and in vivo efficacy studies

Hyaluronic acid (HA) coated irinotecan loaded lignin nanoparticles (HDLNPs) were synthesized using ionic interaction method. Optimized nanoparticles were characterized for their active chemotherapeutic targeting potential to CD44 receptors overly-expressed on cancer cells. Blood component interaction studies supported hemocompatible nature of HDLNPs and also demonstrated their sustained plasma residence property. Cell anti-proliferation and mitochondrial depolarization studies on HT-29 cells suggest significantly (p < 0.01) improved chemotherapeutic efficacy of HDLNPs. In vitro cell based studies showed that nanoparticles have retained antioxidant activity of lignin that can prevent cancer relapse. In vivo biodistribution studies in tumor-bearing Balb/c mice confirmed improved drug localization in tumor site for longer duration. Tumor regression and histopathological studies indicated the efficacy ofligand-assisted targeting chemotherapy over the conventional therapy. Hematological and biochemical estimation suggested that irinotecan-associated myelosuppression, liver steatosis and rare kidney failure can be avoided by its encapsulation in HA-coated lignin nanoparticles. HDLNPs were found to be stable over a period of 12 months.

Recent advances in pharmaceutical and biotechnological applications of lignin-based materials

Lignin, a versatile and abundant biomass-derived polymer, possesses a wide array of properties that makes it a promising material for biotechnological applications. Lignin holds immense potential in the biotechnology and pharmaceutical field due to its biocompatibility, high carbon content, low toxicity, ability to be converted into composites, thermal stability, antioxidant, UV-protectant, and antibiotic activity. Notably, lignin is an environmental friendly alternative to synthetic plastic and fossil-based materials because of its inherent biodegradability, safety, and sustainability potential. The most important findings related to the use of lignin and lignin-based materials are reported in this review, providing an overview of the methods and techniques used for their manufacturing and modification. Additionally, it emphasizes on recent research and the current state of applications of lignin-based materials in the biomedical and pharmaceutical fields and also highlights the challenges and opportunities that need to be overcome to fully realize the potential of lignin biopolymer. An in-depth discussion of recent developments in lignin-based material applications, including drug delivery, tissue engineering, wound dressing, pharmaceutical excipients, biosensors, medical devices, and several other biotechnological applications, is provided in this review article.

In Vivo Toxicological Analysis of MnFe2O4@poly(tBGE-alt-PA) Composite as a Hybrid Nanomaterial for Possible Biomedical Use

Nanocomposites have significantly contributed to biomedical science due to less aggregation behavior and enhanced physicochemical properties. This study synthesized a MnFe2O4@poly(tBGE-alt-PA) nanocomposite for the first time and physicochemically characterized it. The obtained hybrid nanomaterial was tested in vivo for its toxicological properties before use in drug delivery, tissue engineering fields, and environmental applications. The composite was biocompatible with mouse fibroblast cells and hemocompatible with 2% RBC suspension. This nanocomposite was tested on Drosophila melanogaster due to its small size, well-sequenced genome, and low cost of testing. The larvae's crawling speed and direction were measured after feeding. No abnormal path and altered crawling pattern indicated the nonappearance of abnormal neurological disorder in the larva. The gut organ toxicity was further analyzed using DAPI and DCFH-DA dye to examine the structural anomalies. No apoptosis and necrosis were observed in the gut of the fruit fly. Next, adult flies were examined for phenotypic anomalies after their pupal phases emerged. No defects in the phenotypes, including the eye, wings, abdomen, and bristles, were found in our study. Based on these observations, the MnFe2O4@poly(tBGE-alt-PA) composite may be used for various biomedical and environmental applications.

Nanogrinding/ethanol activation facilitating lignin fractionation for preparation of monodispersed lignin nanoparticles

Lignin nanoparticles (LNPs), as one of green and sustainable biological macromolecules, have attracted great attention owing to their promising potentials in many valorized fields. However, the lignin heterogeneity seriously restricts the controllable preparation of LNPs. Herein, a facile nanogrinding activation combining anhydrous ethanol dissolution process was developed to efficiently homogenize lignin prior to gradient ethanol fractionation. Two lignin fractions were obtained from nanogrinding activation/ethanol dissolution followed by gradient ethanol fractionation: L-fractions and S-fractions. Therefore, monodispersed LNPs with unique concave hollow nanostructure and large particle size, and monodispersed LNPs with solid core nanostructure and small particle size were successfully prepared from L-fractions and S-fractions, respectively, via a GVL/water anti-solvent method. The proposed LNPs formation mechanisms facilitated by nanogrinding activation/ethanol dissolution treatment were demonstrated. This study put forwards a facile and green integrated approach for monodispersed LNPs preparation with controllable morphology and particle size.

High value valorization of lignin as environmental benign antimicrobial

Lignin is a natural aromatic polymer of p-hydroxyphenylpropanoids with various biological activities. Noticeably, plants have made use of lignin as biocides to defend themselves from pathogen microbial invasions. Thus, the use of isolated lignin as environmentally benign antimicrobial is believed to be a promising high value approach for lignin valorization. On the other hand, as green and sustainable product of plant photosynthesis, lignin should be beneficial to reduce the carbon footprint of antimicrobial industry. There have been many reports that make use of lignin to prepare antimicrobials for different applications. However, lignin is highly heterogeneous polymers different in their monomers, linkages, molecular weight, and functional groups. The structure and property relationship, and the mechanism of action of lignin as antimicrobial remains ambiguous. To show light on these issues, we reviewed the publications on lignin chemistry, antimicrobial activity of lignin models and isolated lignin and associated mechanism of actions, approaches in synthesis of lignin with improved antimicrobial activity, and the applications of lignin as antimicrobial in different fields. Hopefully, this review will help and inspire researchers in the preparation of lignin antimicrobial for their applications.

Valorization of nano-based lignocellulosic derivatives to procure commercially significant value-added products for biomedical applications

Biowaste, produced from nature, is preferred to be a good source of carbon and ligninolytic machinery for many microorganisms. They are complex biopolymers composed of lignin, cellulose, and hemicellulose traces. This biomass can be depolymerized to its nano-dimensions to gain exceptional properties useful in the field of cosmetics, pharmaceuticals, high-strength materials, etc. Nano-sized biomass derivatives overcome the inherent drawbacks of the parent material and offer promises as a potential material for a wide range of applications with their unique traits such as low-toxicity, biocompatibility, biodegradability and environmentally friendly nature with versatility. This review focuses on the production of value-added products feasible from nanocellulose, nano lignin, and xylan nanoparticles which is quite a novel study of its kind. Dawn of nanotechnology has converted bio waste by-products (hemicellulose and lignin) into useful precursors for many commercial products. Nano-cellulose has been employed in the fields of electronics, cosmetics, drug delivery, scaffolds, fillers, packaging, and engineering structures. Xylan nanoparticles and nano lignin have numerous applications as stabilizers, additives, textiles, adhesives, emulsifiers, and prodrugs for many polyphenols with an encapsulation efficiency of 50%. This study will support the potential development of composites for emerging applications in all aspects of interest and open up novel paths for multifunctional biomaterials in nano-dimensions for cosmetic, drug carrier, and clinical applications.

Chronic exposure to the star polycation (SPc) nanocarrier in the larval stage adversely impairs life history traits in Drosophila melanogaster

BACKGROUND

Nanomaterials are widely used as pesticide adjuvants to increase pesticide efficiency and minimize environmental pollution. But it is increasingly recognized that nanocarrier is a double-edged sword, as nanoparticles are emerging as new environmental pollutants. This study aimed to determine the biotoxicity of a widely applied star polycation (SPc) nanocarrier using Drosophila melanogaster, the fruit fly, as an in vivo model.

RESULTS

The lethal concentration 50 (LC₅₀) value of SPc was identified as 2.14 g/L toward third-instar larvae and 26.33 g/L for adults. Chronic exposure to a sub lethal concentration of SPc (1 g/L) in the larval stage showed long-lasting adverse effects on key life history traits. Exposure to SPc at larval stage adversely impacted the lifespan, fertility, climbing ability as well as stresses resistance of emerged adults. RNA-sequencing analysis found that SPc resulted in aberrant expression of genes involved in metabolism, innate immunity, stress response and hormone production in the larvae. Orally administrated SPc nanoparticles were mainly accumulated in intestine cells, while systemic responses were observed.

CONCLUSIONS

These findings indicate that SPc nanoparticles are hazardous to fruit flies at multiple levels, which could help us to develop guidelines for further large-scale application.

Determination of the Structures of Lignin Subunits and Nanoparticles in Solution by Small-Angle Neutron Scattering: Towards Improving Lignin Valorization

Lignin nanoparticles (LNPs) are usually produced from lignin solution through supersaturation. The structure of the lignin in solution is still poorly understood due to structural variability of isolated lignins. Here, lignins were extracted from different plants to establish a general pattern of their structure in several lignin solvents. Lignin molecules (lignin subunits) and larger aggregates were observed in dimethyl sulfoxide (DMSO), ethylene glycol (EG) and 0.1 N NaOD solutions by small-angle neutron scattering (SANS). It was proposed that the aggregates were composed of lignin subunits with a higher molecular weight and a higher ratio of the aliphatic to phenolic hydroxyl groups. The size, shape, and compactness are important factors that affect the uses of the LNPs, which were obtained from the SANS data for the first time. A discrepancy in the radius between SANS and DLS was discovered, pointing to a large hydration shell around the LNPs in aqueous solutions. The cytotoxicity of the corncob lignin, kraft lignin, and their LNPs were measured and compared.

Role of lignin-based nanoparticles in anticancer drug delivery and bioimaging: An up-to-date review

Lignin, an aromatic biopolymer, is the second most abundant naturally occurring one after cellulose that has drawn a great deal of interest over the years for its potential uses owing to the presence of high content of phenolic compounds, ecofriendly feature and cost-efficiency in comparison to the synthetic polymers. Nevertheless, with the intention of advancing its development, several efforts have been performed in the direction of utilizing lignin on the nanoscale due to its inimitable properties. The notable absorption capacity, fluorescence emission, biodegradability and non-toxicity of lignin nanoparticles permit its appropriateness as a vehicle for drugs and as a bioimaging material. Moreover, lignin nanoparticles have shown plausible therapeutic effects, such as anticancer, antimicrobial, and antioxidant. The current review sheds light on the recent development in the formulation and anticancer applications of lignin nanoparticles as a drug carrier and as a diagnostic tool. The surface properties of the nanomaterial affect the end product characteristics, hence, factors namely; lignin source, isolation technique, purification and quantitation methods, are discussed in this review. This study represents original work that has not been published elsewhere and that has not been submitted simultaneously for publication elsewhere. The manuscript has been read, revised, and approved by the authors.

Recent Advances in Nano-Formulations for Skin Wound Repair Applications

Skin injuries caused by accidents and acute or chronic diseases place a heavy burden on patients and health care systems. Current treatments mainly depend on preventing infection, debridement, and hemostasis and on supplementing growth factors, but patients will still have scar tissue proliferation or difficulty healing and other problems after treatment. Conventional treatment usually focuses on a single factor or process of wound repair and often ignores the influence of the wound pathological microenvironment on the final healing effect. Therefore, it is of substantial research value to develop multifunctional therapeutic methods that can actively regulate the wound microenvironment and reduce the oxidative stress level at the wound site to promote the repair of skin wounds. In recent years, various bioactive nanomaterials have shown great potential in tissue repair and regeneration due to their properties, including their unique surface interface effect, small size effect, enzyme activity and quantum effect. This review summarizes the mechanisms underlying skin wound repair and the defects in traditional treatment methods. We focus on analyzing the advantages of different types of nanomaterials and comment on their toxicity and side effects when used for skin wound repair.

Treating the Onset of Diabetes Using Probiotics Along with Prebiotic from Pachyrhizus erosus in High-Fat Diet Fed Drosophila melanogaster

The increasing mortality due to hypertension and hypercholesterolemia is directly linked with type-2 diabetes. This shows the lethality of the disease. Reports suggest that the prebiotics along with probiotics help in lowering the effects of type-2 diabetes. Prebiotic like inulin is best known for its anti-diabetic effect. The current study utilizes jicama extract as prebiotic source of inulin along with the bacterial strains with probiotic properties (Lactiplantibacillus plantarum and Enterococcus faecium) for treating type-2 diabetes in high-fat diet-induced Drosophila melanogaster model. The high-fat diet-induced Drosophila showed deposition of lipid droplets and formation of micronuclei in the gut. The larva and adult treated with probiotics and synbiotic (probiotic + prebiotic- inulin) comparatively reduced the lipid deposition and micronuclei number in the gut. The increased amount of triglyceride in the whole body of the fatty larva and adult indicated the onset of diabetes. The overexpression of insulin-like genes (Dilp 2) and (Dilp 5) confirmed the insulin resistance, whereas the expression was reduced in the larva and adult supplemented with probiotics and synbiotic. The reactive oxygen species level was reduced with the supplementation of probiotics. The weight, larva size, crawling speed and climbing were also altered in high-fat diet-induced Drosophila melanogaster. The study confirmed the effects of probiotics and synbiotic in successfully lowering diabetes in Drosophila. The study also proved the anti-diabetic potential of the probiotics. Further, it was also confirmed that the probiotics work better in the presence of prebiotic.

Lignin as a Natural Carrier for the Efficient Delivery of Bioactive Compounds: From Waste to Health

Lignin is a fascinating aromatic biopolymer with high valorization potentiality. Besides its extensive value in the biorefinery context, as a renewable source of aromatics lignin is currently under evaluation for its huge potential in biomedical applications. Besides the specific antioxidant and antimicrobial activities of lignin, that depend on its source and isolation procedure, remarkable progress has been made, over the last five years, in the isolation, functionalization and modification of lignin and lignin-derived compounds to use as carriers for biologically active substances. The aim of this review is to summarize the current state of the art in the field of lignin-based carrier systems, highlighting the most important results. Furthermore, the possibilities and constraints related to the physico–chemical properties of the lignin source will be reviewed herein as well as the modifications and processing required to make lignin suitable for the loading and release of active compounds.

Nanomedicine-based strategies to improve treatment of cutaneous leishmaniasis

Nanomedicine strategies were first adapted and successfully translated to clinical application for diseases, such as cancer and diabetes. These strategies would no doubt benefit unmet diseases needs as in the case of leishmaniasis. The latter causes skin sores in the cutaneous form and affects internal organs in the visceral form. Treatment of cutaneous leishmaniasis (CL) aims at accelerating wound healing, reducing scarring and cosmetic morbidity, preventing parasite transmission and relapse. Unfortunately, available treatments show only suboptimal effectiveness and none of them were designed specifically for this disease condition. Tissue regeneration using nano-based devices coupled with drug delivery are currently being used in clinic to address diabetic wounds. Thus, in this review, we analyse the current treatment options and attempt to critically analyse the use of nanomedicine-based strategies to address CL wounds in view of achieving scarless wound healing, targeting secondary bacterial infection and lowering drug toxicity.

A Rapid and Reversible pH Control Process for the Formation and Dissociation of Lignin Nanoparticles

As a new and green type of nanomaterials, lignin nanoparticles (LNPs) have been considered as high-value renewable materials for application in many fields. However, the industrialization of LNPs faces many challenges, such as high manufacturing costs and small-scale production. Here, a simple but rapid and reversible approach for the fabrication of LNPs was provided via switching pH environments. The LNPs were regularly shaped in the acetonitrile/water system, and their size appeared to be very homogeneous. The alternation of forming and dissolving of LNPs could be repeated many times simply by alternately adding acid and alkaline solutions. There was little difference in the molecular structures between the original and regenerated LNPs. In addition, the consumption of solvents for LNPs production was only 200 mL g^-1 , reduced by more than 10 times compared with conventional solvent exchange methods. The concentration of LNPs in the solution also improved to 5.0 g L^-1 . This study not only provides a new, simple, and effective strategy for the fabrication of LNPs but also paves the way towards their real green production and application.

Recent advances in biological activities of lignin and emerging biomedical applications: A short review

As an abundant biopolymer, lignin gains interest owing to its renewable nature and polyphenolic structure. It possesses many biological activities such as antioxidant activity, antimicrobial activity, and biocompatibility. Studies are being carried out to relate the biological activities to the polyphenolic structures. These traits present lignin as a natural compound being used in biomedical field. Lignin nanoparticles (LNPs) are being investigated for safe use in drug and gene delivery, and lignin-based hydrogels are being explored as wound dressing materials, in tissue engineering and 3D printing. In addition, lignin and its derivatives have shown the potential to treat diabetic disease. This review summarizes latest research results on the biological activities of lignin and highlights potential applications exampled by selective studies. It helps to transform lignin from a waste material into valuable materials and products.

A recent advancement on preparation, characterization and application of nanolignin

Each year, 50 to 70 million tonnes of lignin are produced worldwide as by-products from pulp industries and biorefineries through numerous processes. Nevertheless, about 98% of lignin is directly burnt to produce steam to generate energy for the pulp mills and only a handful of isolated lignin is used as a raw material for the chemical conversion and for the preparation of various substances as well as modification of lignin into nanomaterials. Thus, thanks to its complex structure, the conversion of lignin to nanolignin, attracting growing attention and generating considerable interest in the scientific community. The objective of this review is to provide a complete understanding and knowledge of the synthesis methods and functionalization of various lignin nanoparticles (LNP). The characterization of LNP such as structural, thermal, molecular weight properties together with macromolecule and quantification assessments are also reviewed. In particular, emerging applications in different areas such as UV barriers, antimicrobials, drug administration, agriculture, anticorrosives, the environment, wood protection, enzymatic immobilization and others were highlighted. In addition, future perspectives and challenges related to the development of LNP are discussed.

High-Molecular-Weight Fractions of Spruce and Eucalyptus Lignin as a Perspective Nanoparticle-Based Platform for a Therapy Delivery in Liver Cancer

The natural polymer, lignin, possesses unique biodegradable and biocompatible properties, making it highly attractive for the generation of nanoparticles for targeted cancer therapy. In this study, we investigated spruce and eucalyptus lignin nanoparticles (designated as S-and E-LNPs, respectively). Both LNP types were generated from high-molecular-weight (M_w) kraft lignin obtained as insoluble residues after a five-step solvent fractionation approach, which included ethyl acetate, ethanol, methanol, and acetone. The resulting S-and E-LNPs ranged in size from 16 to 60 nm with uniform spherical shape regardless of the type of lignin. The preparation of LNPs from an acetone-insoluble lignin fraction is attractive because of the use of high-M_w lignin that is otherwise not suitable for most polymeric applications, its potential scalability, and the consistent size of the LNPs, which was independent of increased lignin concentrations. Due to the potential of LNPs to serve as delivery platforms in liver cancer treatment, we tested, for the first time, the efficacy of newly generated E-LNPs and S-LNPs in two types of primary liver cancer, hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), in vitro. Both S-LNPs and E-LNPs inhibited the proliferation of HCC cells in a dose-dependent manner and did not affect CCA cell line growth. The inhibitory effect toward HCC was more pronounced in the E-LNP-treated group and was comparable to the standard therapy, sorafenib. Also, E-LNPs induced late apoptosis and necroptosis while inhibiting the HCC cell line. This study demonstrated that an elevated number of carbohydrates on the surface of the LNPs, as shown by NMR, seem to play an important role in mediating the interaction between LNPs and eukaryotic cells. The latter effect was most pronounced in E-LNPs. The novel S- and E-LNPs generated in this work are promising materials for biomedicine with advantageous properties such as small particle size and tailored surface functionality, making them an attractive and potentially biodegradable delivery tool for combination therapy in liver cancer, which still has to be verified in vivo using HCC and CCA models.

How far is Lignin from being a biomedical material?

Lignin is a versatile biomass that possesses many different desirable properties such as antioxidant, antibacterial, anti-UV, and good biocompatibility. Natural lignin can be processed through several chemical processes. The processed lignin can be modified into functionalized lignin through chemical modifications to develop and enhance biomaterials. Thus, lignin is one of the prime candidate for various biomaterial applications such as drug and gene delivery, biosensors, bioimaging, 3D printing, tissue engineering, and dietary supplement additive. This review presents the potential of developing and utilizing lignin in the outlook of new and sustainable biomaterials. Thereafter, we also discuss on the challenges and outlook of utilizing lignin as a biomaterial.

Lignin Nanoparticles Deliver Novel Thymine Biomimetic Photo-Adducts with Antimelanoma Activity

We report here the synthesis of novel thymine biomimetic photo-adducts bearing an alkane spacer between nucleobases and characterized by antimelanoma activity against two mutated cancer cell lines overexpressing human Topoisomerase 1 (TOP1), namely SKMEL28 and RPMI7951. Among them, Dewar Valence photo-adducts showed a selectivity index higher than the corresponding pyrimidine-(6-4)-pyrimidone and cyclobutane counterpart and were characterized by the highest affinity towards TOP1/DNA complex as evaluated by molecular docking analysis. The antimelanoma activity of novel photo-adducts was retained after loading into UV photo-protective lignin nanoparticles as stabilizing agent and efficient drug delivery system. Overall, these results support a combined antimelanoma and UV sunscreen strategy involving the use of photo-protective lignin nanoparticles for the controlled release of thymine dimers on the skin followed by their sacrificial transformation into photo-adducts and successive inhibition of melanoma and alert of cellular UV machinery repair pathways.

Experimental and Simulation Study of the Solvent Effects on the Intrinsic Properties of Spherical Lignin Nanoparticles

Spherical lignin nanoparticles (LNPs) fabricated via nanoprecipitation of dissolved lignin are among the most attractive biomass-derived nanomaterials. Despite various studies exploring the methods to improve the uniformity of LNPs or seeking more application opportunities for LNPs, little attention has been given to the fundamental aspects of the solvent effects on the intrinsic properties of LNPs. In this study, we employed a variety of experimental techniques and molecular dynamics (MD) simulations to investigate the solvent effects on the intrinsic properties of LNPs. The LNPs were prepared from softwood Kraft lignin (SKL) using the binary solvents of aqueous acetone or aqueous tetrahydrofuran (THF) via nanoprecipitation. The internal morphology, porosity, and mechanical properties of the LNPs were analyzed with electron tomography (ET), small-angle X-ray scattering (SAXS), atomic force microscopy (AFM), and intermodulation AFM (ImAFM). We found that aqueous acetone resulted in smaller LNPs with higher uniformity compared to aqueous THF, mainly ascribing to stronger solvent–lignin interactions as suggested by MD simulation results and confirmed with aqueous 1,4-dioxane (DXN) and aqueous dimethyl sulfoxide (DMSO). More importantly, we report that both LNPs were compact particles with relatively homogeneous density distribution and very low porosity in the internal structure. The stiffness of the particles was independent of the size, and the Young’s modulus was in the range of 0.3–4 GPa. Overall, the fundamental understandings of LNPs gained in this study are essential for the design of LNPs with optimal performance in applications.

A Review of Adsorbents for Heavy Metal Decontamination: Growing Approach to Wastewater Treatment

Heavy metal is released from many industries into water. Before the industrial wastewater is discharged, the contamination level should be reduced to meet the recommended level as prescribed by the local laws of a country. They may be poisonous or cancerous in origin. Their presence does not only damage people, but also animals and vegetation because of their mobility, toxicity, and non-biodegradability into aquatic ecosystems. The review comprehensively discusses the progress made by various adsorbents such as natural materials, synthetic, agricultural, biopolymers, and commercial for extraction of the metal ions such as Ni2+, Cu2+, Pb2+, Cd2+, As2+ and Zn2+ along with their adsorption mechanisms. The adsorption isotherm indicates the relation between the amount adsorbed by the adsorbent and the concentration. The Freundlich isotherm explains the effective physical adsorption of the solute particle from the solution on the adsorbent and Langmuir isotherm gives an idea about the effect of various factors on the adsorption process. The adsorption kinetics data provide valuable insights into the reaction pathways, the mechanism of the sorption reaction, and solute uptake. The pseudo-first-order and pseudo-second-order models were applied to describe the sorption kinetics. The presented information can be used for the development of bio-based water treatment strategies.

Prevention of infection caused by enteropathogenic E. coli O157:H7 in intestinal cells using enrofloxacin entrapped in polymer based nanocarriers

Poor bioavailability of antibiotics, toxicity, and development of antibiotic-resistant bacteria jeopardize antibiotic treatments. To circumvent these issues, drug delivery using nanocarriers are highlighted to secure the future of antibiotic treatments. This work investigated application of nanocarriers, to prevent and treat bacterial infection, presenting minimal toxicity to the IPEC-J2 cell line. To accomplish this, polymer-based nanoparticles (NPs) of poly(lactide-co-glycolide) (PLGA) and lignin-graft-PLGA (LNP) loaded with enrofloxacin (ENFLX) were synthesized, yielding spherical particles with average sizes of 111.8 ± 0.6 nm (PLGA) and 117.4 ± 0.9 nm (LNP). The releases of ENFLX from PLGA and LNP were modeled by a theoretical diffusion model considering both the NP and dialysis diffusion barriers for drug release. Biocompatible concentrations of ENFLX, enrofloxacin loaded PLGA(Enflx) and LNP(Enflx) were determined based on examination of bacterial inhibition, toxicity, and ROS generation. Biocompatible concentrations were used for treatment of higher- and lower-level infections in IPEC-J2 cells. Prevention of bacterial infection by LNP(Enflx) was enhanced more than 50% compared to ENFLX at lower-level infection. At higher-level infection, PLGA(Enflx) and LNP(Enflx) demonstrated 25% higher prevention of bacteria growth compared to ENFLX alone. The superior treatment achieved by the nanocarried drug is accredited to particle uptake by endocytosis and slow release of the drug intracellularly, preventing rapid bacterial growth inside the cells.

Microfluidic Synthesis of Lignin/Chitosan Nanoparticles for the pH-Responsive Delivery of Anticancer Drugs

In this work, lignin/chitosan nanoparticles (Lig/Chi NPs) with controlled structures were synthesized in a simple and scalable microfluidic system. When the positively charged chitosan and the negatively charged lignin solution were blended in a microreactor, Lig/Chi NPs were rapidly formed via the electrostatic coassembly between the amino groups of chitosan and the carboxyl groups of lignin. The ζ potential changes from negative (-13 mV) to positive (+54.5 mV) for Lig NPs and Lig/Chi NPs, respectively. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results demonstrated that Lig/Chi NPs have an average particle size of about 180 nm, which can be used as nanocarriers for drug delivery. The anticancer drug nanoparticles with docetaxel (DTX) and curcumin (CCM) were prepared by coassembly with Lig/Chi NPs in a microreactor, which had good drug loading efficiency, biocompatibility, and can release drugs in response to pH in the weakly acidic environment of the tumor. The drug release amounts in acidic solutions that simulated the tumor microenvironment were 51% (DTX@Lig/Chi NPs) and 50% (CCM@Lig/Chi NPs), respectively, which were better than the release amounts at pH 7.4, and have an obvious killing effect on HeLa cells.

Recent advances in porous nanostructures for cancer theranostics

Porous nanomaterials with high surface area, tunable porosity, and large mesopores have recently received particular attention in cancer therapy and imaging. Introduction of additional pores to nanostructures not only endows the tunability of optoelectronic and optical features optimal for tumor treatment, but also modulates the loading capacity and controlled release of therapeutic agents. In recognition, increasing efforts have been made to fabricate various porous nanomaterials and explore their potentials in oncology applications. Thus, a systematic and comprehensive summary is necessary to overview the recent progress, especially in last ten years, on the development of various mesoporous nanomaterials for cancer treatment as theranostic agents. While outlining their individual synthetic mechanisms after a brief introduction of the structures and properties of porous nanomaterials, the current review highlighted the representative applications of three main categories of porous nanostructures (organic, inorganic, and organic-inorganic nanomaterials). In each category, the synthesis, representative examples, and interactions with tumors were further detailed. The review was concluded with deliberations on the key challenges and future outlooks of porous nanostructures in cancer theranostics.

Lignin, lipid, protein, hyaluronic acid, starch, cellulose, gum, pectin, alginate and chitosan-based nanomaterials for cancer nanotherapy: Challenges and opportunities

Although nanotechnology-driven drug delivery systems are relatively new, they are rapidly evolving since the nanomaterials are deployed as effective means of diagnosis and delivery of assorted therapeutic agents to targeted intracellular sites in a controlled release manner. Nanomedicine and nanoparticulate drug delivery systems are rapidly developing as they play crucial roles in the development of therapeutic strategies for various types of cancer and malignancy. Nevertheless, high costs, associated toxicity and production of complexities are some of the critical barriers for their applications. Green nanomedicines have continually been improved as one of the viable approaches towards tumor drug delivery, thus making a notable impact on which considerably affect cancer treatment. In this regard, the utilization of natural and renewable feedstocks as a starting point for the fabrication of nanosystems can considerably contribute to the development of green nanomedicines. Nanostructures and biopolymers derived from natural and biorenewable resources such as proteins, lipids, lignin, hyaluronic acid, starch, cellulose, gum, pectin, alginate, and chitosan play vital roles in the development of cancer nanotherapy, imaging and management. This review uncovers recent investigations on diverse nanoarchitectures fabricated from natural and renewable feedstocks for the controlled/sustained and targeted drug/gene delivery systems against cancers including an outlook on some of the scientific challenges and opportunities in this field. Various important natural biopolymers and nanomaterials for cancer nanotherapy are covered and the scientific challenges and opportunities in this field are reviewed.

Reactive oxygen species: the root cause of nanoparticle-induced toxicity in Drosophila melanogaster

Nanotechnology is a rapidly developing technology in the twenty-first century. Nanomaterials are extensively used in numerous industries including cosmetics, food, medicines, industries, agriculture, etc. Along with its wide application toxicity is also reported from studies of various model organisms including Drosophila. The toxicity reflects cytotoxicity, genotoxicity, and teratogenicity. The current study correlates the toxicity as a consequence of reactive oxygen species (ROS) generated owing to the presence of nanoparticles with the living cell. ROS mainly includes hydroxyl ions, peroxide ions, superoxide anions, singlet oxygen, and hypochlorous acids. An elevated level of ROS can damage the cells by various means. To protect the body from excess ROS, living cells possess a set of antioxidant enzymes which includes peroxidase, glutathione peroxidase, and catalase. If the antioxidant enzymes cannot nullify the elevated ROS level than DNA damage, cell damage, cytotoxicity, apoptosis, and uncontrolled cell regulations occur resulting in abnormal physiological and genotoxic conditions. Herewith, we are reporting various morphological and physiological defects caused after nanoparticle treatment as a function of redox imbalance.