Experimental and mathematical studies on the drug release properties of aspirin loaded chitosan nanoparticles

Silibinin-loaded chitosan-capped silver nanoparticles exhibit potent antimicrobial, antibiofilm, and anti-inflammatory activity against drug-resistant nosocomial pathogens

Nanoparticles capped with natural products can be a cost-effective alternative to treat drug-resistant nosocomial infections. Therefore, silibinin-loaded chitosan-capped silver nanoparticles (S-C@AgNPs) were synthesized to evaluate their antimicrobial and anti-inflammatory potential. The S-C@AgNPs plasmon peak was found at 430 nm and had a particle size distribution of about 130 nm with an average hydrodynamic diameter of 101.37 nm. The Scanning Electron Microscopy images showed the presence of sphere-shaped homogeneous nanoparticles. The Fourier Transform Infrared Spectroscopy analysis confirmed the loading of silibinin and chitosan on the AgNPs surface. The minimum inhibitory concentration of the S-C@AgNPs was reported between 3.12 μg/ml to 12.5 μg/ml and a minimum bactericidal concentration between 6.25 μg/ml to 25 μg/ml against drug-resistant nosocomial pathogens. Moreover, concentration-dependent significant inhibition of the biofilm formation was reported against P. aeruginosa (70.21%) and K. pneumoniae (71.02%) at 30 μg/ml, and the highest destruction of preformed biofilm was observed at 100 μg/ml against P. aeruginosa (89.74%) and K. pneumoniae (77.65%) as compared to individual bacterial control. Additionally, the fluorescence live/dead assay for bacterial biofilm confirmed that 100 µg/ml effectively inhibits the biofilm formed by these pathogens. S-C@AgNPs also showed anti-inflammatory activity, which is evident by the significant decrease in the proinflammatory cytokines and chemokines level in THP1 cells treated with LPS. This study concluded that S-C@AgNPs have potent antimicrobial, antibiofilm, and anti-inflammatory properties and could be a potential option for treating drug resistant nosocomial infections.

In vitro profiling and molecular dynamics simulation studies of berberine loaded MCM-41 mesoporous silica nanoparticles to prevent neuronal apoptosis

Neuronal loss in Alzheimer's disease has been reported to display features of apoptosis, pyroptosis (programmed necrosis), or necroptosis. This study thoroughly examines the production and characterization of MCM-41 based berberine (BBR)-loaded porous silica nanoparticles (MSNs) by a modified Stöber method, focusing on their possible role in inhibiting the apoptotic process. Particle size, polydispersity index, morphology, drug loading, zeta potential, entrapment efficiency, and drug release were examined. The formulation was analyzed using various spectroscopic techniques. The surface area was computed by the Brunauer-Emmett-Teller plot. Computational models were developed for molecular dynamics simulation studies. A small PDI value indicated an even distribution of particles at nanoscale sizes (80-100 nm). Results from XRD and SEAD experiments confirmed the amorphous nature of BBR in nanoparticles. Nanoparticles had high entrapment (75.21 ± 1.55%) and drug loading (28.16 ± 2.5%) efficiencies. A negative zeta potential value (-36.861.1 mV) indicates the presence of silanol groups on the surface of silica. AFM findings reveal bumps due to the surface drug that contributed to the improved roughness of the MSNs-BBR surface. Thermal gravimetric analysis confirmed the presence of BBR in MSNs. Drug release was controlled by simple diffusion or quasi-diffusion. Molecular dynamics simulations confirmed the existence of diffused drug molecules. Cellular studies using SH-SY-5Y cells revealed dose-dependent growth inhibition. Fragmented cell nuclei and nuclear apoptotic bodies in DAPI-stained cells exposed to nanoparticles showed an increase in apoptotic cells. Flow cytometry analysis demonstrated a lower red-to-green ratio in SH-SY-5Y cells treated with nanoparticles. This suggests improved mitochondrial health, cellular viability restoration, and prevention of the apoptotic process. This study provides essential data on the synthesis and potential of MSNs loaded with BBR, which may serve as a viable therapeutic intervention for conditions associated with apoptosis.

Pomegranate extract-loaded sphingosomes for the treatment of cancer: Phytochemical investigations, formulation, and antitumor activity evaluation

AIM

Formulation of Pomegranate Extracts (PE)-loaded sphingosomes as an antitumor therapy for the intravenous and passive targeted delivery to various tumor types, especially that of the breast, colon, and uterus; to increase the therapeutic activity and decrease the adverse effects profile.

METHODS

The pericarp and seeds' juice of Punica granatum were each extracted using D.W. and ethanol. Phytochemical investigation of all extracts was carried out including total phenolics, flavonoids, and anthocyanins contents, the antioxidant activity, as well as HPLC analysis of phenolics and flavonoids. The antitumor potential of all extracts was also tested utilizing three cell lines: MCF-7, HeLa, and HCT116. The candidate extract was chosen for the formulation phase and was entrapped into the sphingosomes using the thin-film hydration method and employing three different PE: lipids weight ratios. The synthesized formulations were characterized for their size, morphological features, zeta potential, entrapment efficiency, and in vitro drug release and kinetics modeling studies. The optimized formula was further analyzed by FTIR spectroscopy and electron microscopy. The antitumor activity of F2 was also investigated using the same cancer cell lines compared to the plant extract.

RESULTS

The highest phenolics, flavonoids, and anthocyanins contents were observed in the ethanolic pericarps extract (EPE), followed by the ethanolic seeds extract (ESE). Consequently, EPE showed a higher antitumor activity hence it was selected for the formulation phase. PE-loaded sphingosomes formula (F2) was selected for having the highest EE% (71.64%), and a sustained release profile with the highest in vitro release (42.5±9.44%). By employing the DDSolver, the Weibull model was found the most suitable to describe the PE release kinetics compared to other models. The release mechanism was found to follow Fickian diffusion. Simulated pharmacokinetic parameters have portrayed F2 as the candidate formula, with the highest AUC (536.095) and slowest MDT (0.642 h). In addition, F2 exhibited a significant (p>0.05) stronger and prolonged anticancer effect against MCF-7, HeLa, and HCT116 cell lines at all concentrations tested compared to the free extract.

CONCLUSION

The results proved that sphingosomes are an effective delivery system, improving pharmacological efficacy and reducing serious side effects of anticancer medications and natural products.

Dual-functional DNA nanogels for anticancer drug delivery

DNA hydrogels with unique sequence programmability on nucleic acid framework manifest remarkable attributes, such as high payload capacities, biocompatibility and biosafety. The availability of DNA nanogels with multimodal functionalities remains limited due to the absence of facile gelation methods applicable at the nanometer scale. Here, we developed a one-step assembly of DNA dendrimers into nanogels (DNG) with couple hundred nanometers size. DNG showed robust stability against physical forces and biological degradation for easy purification and sustainable drug release. Long-term stability either in powder or aqueous solution endows DNG easy for shipping, handling and storage. By encoding dual functionalities into separate branches on DNA dendrimers, DNG can accommodate chemodrugs and aptamers with distinctive loading moduli. DNG significantly enhanced the drug efficacy against cancerous cells while minimizing cytotoxicity towards somatic cells, as demonstrated in vitro and in xenografted mice models of breast cancer. Thus, due to their facile assembly and storage, bi-entity encoding, and inherent biocompatibility, DNG exhibits immense prospects as nanoscale vesicles for the synergistic delivery of multimodal theranostics in anticancer treatments. STATEMENT OF SIGNIFICANCE: DNA nanogels were self-assembled via a facile protocol utilizing a DNA dendrimer structure. These nanogels displayed robust stability against physical forces, permitting long term storage in concentrated solutions or as a powder. Furthermore, they exhibited resilience to biological degradation, facilitating sustained drug release. The bi-entity encoded dendritic branches conferred dual functionalities, enabling both chemodrug encapsulation and the presentation of aptamers as targeting motifs. In vivo investigations confirmed the nanogels provide high efficacy in tumor targeting and chemotherapy with enhanced drug efficacy and reduced side effects.

Graphite nanopowder incorporated xanthan gum scaffold for effective bone tissue regeneration purposes with improved biomineralization

In the current work, biomaterial composed of Xanthan gum and Diethylene glycol dimethacrylate with impregnation of graphite nanopowder filler in their matrices was fabricated successfully for their potential usage in the engineering of bone defects. Various physicochemical properties associated with the biomaterial were characterized using FTIR, XRD, TGA, SEM etc. The biomaterial rheological studies imparted the better notable properties associated with the inclusion of graphite nanopowder. The biomaterial synthesized exhibited a controlled drug release. Adhesion and proliferation of different secondary cell lines do not generate ROS on the current biomaterial and thus show its biocompatibility and non-toxic nature. The synthesized biomaterial's osteogenic potential on SaOS-2 cells was supported by increased ALP activity, enhanced differentiation and biomineralization under osteoinductive circumstances. The current biomaterial demonstrates that in addition to the drug-delivery applications, it can also be a cost-effective substrate for cellular activities and has all the necessary properties to be considered as a promising alternative material suitable for repairing and restoring bone tissues. We propose that this biomaterial may have commercial importance in the biomedical field.

Apocynin and its chitosan nanoparticles attenuated cisplatin-induced multiorgan failure: Synthesis, characterization, and biological evaluation

Cisplatin (CDDP) is an effective chemotherapeutic drug that has been used successfully in treating various tumors. Although its higher antineoplastic agent activity, CDDP exhibited severe side effects that limit its use. CDDP-induced toxicity is attributed to oxidative stress and inflammation. Apocynin (APO) is a bioactive phytochemical with potent antioxidant and anti-inflammatory properties. However, pharmaceutical experts face significant hurdles due to the limited bioavailability and quick elimination of APO. Therefore, we synthesized a chitosan (CTS)-based nano delivery system using the ionic gelation method to enhance APO bioactivity. CTS-APO-NPs were characterized using different physical and chemical approaches, including FTIR, XRD, TGA, Zeta-sizer, SEM, and TEM. In addition, the protective effect of CTS-APO-NPs against CDDP-induced nephrotoxicity, hepatotoxicity, and cardiotoxicity in rats was evaluated. CTS-APO-NPs restored serum biomarkers and antioxidants to their normal levels. Also, histopathological examination was used to assess the recovery of heart, kidney, and liver tissues. CTS-APO-NPs attenuated the oxidative stress mediated by Nrf2 activation while it dampened inflammation mediated by NF-κB suppression. CTS-APO-NPs is a potentially attractive target for more therapeutic trials.

Pollen-derived microcapsules for aspirin microencapsulation: in vitro release and physico-chemical studies

Aspirin, also known as acetylsalicylic acid (ASA), is one of the most crucial therapies needed and/or used in a basic health system. Using biocompatible materials to encapsulate ASA would improve its therapeutic efficacy and reduce its side effects via controlled release in physiological environments. Consequently, we explore in this study the feasibility of encapsulation of ASA into robust Lycopodium clavatum L. sporopollenin (LCS) microcapsules. After extracting sporopollenin from their natural micrometer-sized raw spores, the physico-chemical features of the extracted sporopollenin, pure ASA, and sporopollenin loaded with ASA were characterised using various methods, including optical microscopy, Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-vis.) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Additionally, we demonstrate the in vitro release profile of ASA in a triggered gastrointestinal environment utilizing kinetics analysis to investigate the mechanism of release. The LCS microcapsules were found to be excellent encapsulants for the crucial ASA drug and achieved controlled in vitro release, that would enable further investigations to rationally design versatile controlled delivery platforms.

Aspirin effect on bone remodeling and skeletal regeneration: Review article

Bone tissues are one of the most complex tissues in the body that regenerate and repair themselves spontaneously under the right physiological conditions. Within the limitations of treating bone defects, mimicking tissue engineering through the recruitment of scaffolds, cell sources and growth factors, is strongly recommended. Aspirin is one of the non-steroidal anti-inflammatory drugs (NSAIDs) and has been used in clinical studies for many years due to its anti-coagulant effect. On the other hand, aspirin and other NSAIDs activate cytokines and some mediators in osteoclasts, osteoblasts and their progenitor cells in a defect area, thereby promoting bone regeneration. It also stimulates angiogenesis by increasing migration of endothelial cells and the newly developed vessels are of emergency in bone fracture repair. This review covers the role of aspirin in bone tissue engineering and also, highlights its chemical reactions, mechanisms, dosages, anti-microbial and angiogenesis activities.

Biocompatibility and cytotoxicity in vitro of surface-functionalized drug-loaded spinel ferrite nanoparticles

In this study, poly(isobutylene-alt-maleic anhydride) (PMA)-coated spinel ferrite (MFe2O4, where M = Fe, Co, Ni, or Zn) nanoparticles (NPs) were developed as carriers of the anticancer drugs doxorubicin (DOX) and methotrexate (MTX). Physical characterizations confirmed the formation of pure cubic structures (14-22 nm) with magnetic properties. Drug-loaded NPs exhibited tumor specificity with significantly higher (p < 0.005) drug release in an acidic environment (pH 5.5). The nanoparticles were highly colloidal (zeta potential = -35 to -26 mV) in deionized water, phosphate buffer saline (PBS), and sodium borate buffer (SBB). They showed elevated and dose-dependent cytotoxicity in vitro compared to free drug controls. The IC50 values ranged from 0.81 to 3.97 μg/mL for HepG2 and HT144 cells, whereas IC50 values for normal lymphocytes were 10 to 35 times higher (18.35-43.04 µg/mL). Cobalt ferrite (CFO) and zinc ferrite (ZFO) NPs were highly genotoxic (p < 0.05) in cancer cell lines. The nanoparticles caused cytotoxicity via oxidative stress, causing DNA damage and activation of p53-mediated cell cycle arrest (significantly elevated expression, p < 0.005, majorly G1 and G2/M arrest) and apoptosis. Cytotoxicity testing in 3D spheroids showed significant (p < 0.05) reduction in spheroid diameter and up to 74 ± 8.9% of cell death after two weeks. In addition, they also inhibited multidrug resistance (MDR) pump activity in both cell lines suggesting effectivity in MDR cancers. Among the tested MFe2O4 NPs, CFO nanocarriers were the most favorable for targeted cancer therapy due to excellent magnetic, colloidal, cytotoxic, and biocompatible aspects. However, detailed mechanistic, in vivo cytotoxicity, and magnetic-field-assisted studies are required to fully exploit these nanocarriers in therapeutic applications.

Lipid-Coated MCM-41 Mesoporous Silica Nanoparticles Loaded with Berberine Improved Inhibition of Acetylcholine Esterase and Amyloid Formation

Selective permeability of the blood-brain barrier limits effective treatment of neurodegenerative disorders. In the present study, brain-targeted lipid-coated mesoporous silica nanoparticles (MSNs) containing berberine (BBR) were synthesized for the effective treatment of Alzheimer's disease (AD). The study involved synthesis of Mobil Composition of Matter-41 (MCM-41) mesoporous silica nanoparticles (MSNs), BBR loading, and lipid coating of MSNs (MSNs-BBR-L) and in vitro and in vivo characterization of MSNs-BBR-L. The liposomes (for lipid coating) were prepared by the thin-film hydration method. Transmission electron microscopy (TEM) images indicated 5 nm thickness of the lipid coating. Dynamic light scattering (DLS) and TEM results confirmed that the size of synthesized MSNs-BBR-L was in the range of 80-100 nm. The X-ray diffraction (XRD) pattern demonstrated retention of the ordered structure of BBR after encapsulation and lipid coating. Fourier transform infrared (FTIR) spectrum confirmed the formation of a lipid coat over the MSN particles. MSNs-BBR-L displayed significantly (p < 0.05) higher acetylcholine esterase (AChE) inhibitory activity. The study confirmed significant (p < 0.05) amyloid fibrillation inhibition and decreased the malondialdehyde (MDA) level by MSNs-BBR-L. Pure BBR- and MSNs-BBR-L-treated AD animals showed a significant decrease in the BACE-1 level compared to scopolamine-intoxicated mice. Eight times higher area under the curve for MSNs-BBR-L (2400 ± 27.44 ng h/mL) was recorded compared to the pure BBR (295.5 ± 0.755 ng h/mL). Overall, these results highlight the utility of MSNs-BBR-L as promising drug delivery vehicles for brain delivery of drugs.

Modeling of Anti-cancer Drug Release Kinetics from Liposomes and Micelles: A review

Nanocarriers, such as liposomes and micelles, were developed to enhance the delivery of therapeutic drugs to malignant tissues. Internal or external stimuli can be applied to achieve spatiotemporal controlled release from these carriers. This will result in enhancing their therapeutic efficacy while reducing toxicity. Mathematical modeling is used to simulate drug release from nanocarriers; this will facilitate and optimize the development and design of desirable nanocarriers in a systematic manner, rather than a trial-and-error approach. This review summarizes nine mathematical models often used to simulate drug release from nanocarriers and reviews studies which employed these models to simulate drug release from conventional as well as temperature-, pH-, and ultrasound-triggered micelles and liposomes.

Noyes-Whitney Dissolution Model-Based pH-Sensitive Slow Release of Paclitaxel (Taxol) from Human Hair-Derived Keratin Microparticle Carriers

This paper describes a convenient and straightforward method developed to extract keratin particles (KPs) from human hair. It also involves their characterization by several methods and encapsulation of the anticancer drug Paclitaxel (Taxol) within them, aiming for targeted delivery to cancerous sites and slow release at their vicinity. The KPs obtained were in micrometer in size. They are capable of encapsulating Taxol within them with a high encapsulation efficiency of 56% and a drug loading capacity of 2.360 g of Taxol per g keratin. As revealed by the SEM elemental analysis, KPs do not contain any toxic metal ion, and hence, they pose no toxicity to human cells. The pH-dependent release kinetics of the drug from KPs indicates that the drug is released faster when the pH of the solution is increased in the 5.0 to 7.0 pH range. The release kinetics obtained is impressive, and once targeted to the cancerous sites, using cancer directing agents, such as folic acid; a glutamate urea ligand known as DUPA; aminopeptidase N, also known as CD13; and FAP-α-targeting agents, the slow release of the drug is expected to destroy only the cancerous cells. The Noyes-Whitney dissolution model was used to analyze the release behavior of Taxol from KPs, which shows excellent fitting with experimental data. The pH dependence of drug release from keratin is also explained using the 3-D structures and keratin stability at different pH values.

Improvement of the Solubility Amphotericin B Using Olive Oil Nanoemulsion Coated with Chitosan for More Effective Treatment of Zoonotic Cutaneous Leishmaniasis

Amphotericin B (AMB) is a macrolide polyene antibiotic presenting potent anti-cutaneous leishmania activity. Nonetheless, its low water solubility, side effects, and toxicity have limited its therapeutic efficiency. The present study aimed to improve the solubility of AmB in oil-in-water using chitosan and determine its cytotoxicity on macrophages, as well as Leishmania major promastigote and amastigote. Olive oil, span 80, tween 80, AmB, and DMSO were employed as excipients, and nanoemulsions (NEs) were prepared by sonicator bath at 37 °C for 1 h at the highest power and stirred overnight with pH 5.5. Thereafter, chitosan was added to the NE and stirred overnight to obtain chitosan nanoemulsion (CNE). The CNE was optimized and investigated for different in-vitro parameters, such as droplet size, zeta potential, morphology, drug content, in-vitro drug release, and in-vitro cytotoxicity. Droplet size and zeta potential for CNE with AmB were obtained at 13.33 ± 1.3 nm, 30.90 ± 1.9 mV, respectively. Encapsulation efficiency and drug loading of the final CNE were reported as 100% and 0.64%, respectively. The results of in-vitro cytotoxicity revealed that CNE did not cause any cytotoxicity in macrophages. The CNE not only reduced drug toxicity for the macrophage but also had a suitable inhibition effect on the parasite. The CNE with AmB exerted an inhibitory effect on L. major promastigote/ amastigote phase. Furthermore, CNE with AmB represented a promising approach for leishmaniasis treatment. Therefore, the obtained outcomes of the IC₅₀ proposed that the application of CNE can cause no toxicity and guarantees better quality drug release.

Codelivery of BV6 and anti-IL6 siRNA by hyaluronate-conjugated PEG-chitosan-lactate nanoparticles inhibits tumor progression

AIMS

Increased expression of inhibitor of apoptosis (IAP) genes has been associated with progressive cancer and chemoresistance. Accordingly, blockade of IAPs by BV6 has resulted in ameliorative outcomes. Interleukin (IL)-6 is another important mediator involved in the growth and survival of tumor cells. Therefore, we hypothesized that simultaneous inhibition of IAPs and IL-6 could be a new promising anti-tumor treatment strategy.

MATERIALS AND METHODS

In this study, we generated and characterized hyaluronate-PEG-Chitosan-Lactate (H-PCL) nanoparticles (NPs) to simultaneously deliver IL6-specific siRNA and BV6 to 4T1 (breast cancer) and CT26 (colon cancer) cells, and investigate the anti-tumor properties of this combination therapy both in vitro and in vivo.

KEY FINDINGS

H-PCL NPs exhibited good physicochemical properties leading to efficient transfection of cancer cells and suppression of target molecules. Moreover, combination therapy synergistically increased apoptosis, as well as decreased cell migration, proliferation, colony formation, and angiogenesis in both 4T1 and CT26 cell lines and suppressed cancer progression in tumor-bearing mice that was associated with enhanced survival time.

SIGNIFICANCE

These findings imply the effectiveness of cancer combination therapy by using H-PCL NPs loaded with anti-IL-6 siRNA and BV6.

l-Ascorbic Acid and Thymoquinone Dual-Loaded Palmitoyl-Chitosan Nanoparticles: Improved Preparation Method, Encapsulation and Release Efficiency

Encapsulation of dual compounds of different characters (hydrophilic and hydrophobic) in single nanoparticles carrier could reach the site of action more accurately with the synergistic effect but it is less investigated. In our previous findings, combined-compounds encapsulation and delivery from chitosan nanoparticles were impaired by the hydrophilicity of chitosan. Therefore, hydrophobic modification on chitosan with palmitic acid was conducted in this study to provide an amphiphilic environment for better encapsulation of antioxidants; hydrophobic thymoquinone (TQ) and hydrophilic l-ascorbic acid (LAA). Palmitoyl chitosan nanoparticles (PCNPs) co-loaded with TQ and LAA (PCNP-TQ-LAA) were synthesized via the ionic gelation method. Few characterizations were conducted involving nanosizer, Fourier-transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). UV–VIS spectrophotometry was used to analyze the encapsulation and release efficiency of the compounds in PCNPs. Successfully modified PCNP-TQ-LAA had an average particle size of 247.7 ± 24.0 nm, polydispersity index (PDI) of 0.348 ± 0.043 and zeta potential of 19.60 ± 1.27 mV. Encapsulation efficiency of TQ and LAA in PCNP-TQ-LAA increased to 64.9 ± 5.3% and 90.0 ± 0%, respectively. TQ and LAA in PCNP-TQ-LAA system showed zero-order release kinetics, with a release percentage of 97.5% and 36.1%, respectively. Improved preparation method, encapsulation and release efficiency in this study are anticipated to be beneficial for polymeric nanocarrier development.

PLGA nanoparticles loaded with Gallic acid- a constituent of Leea indica against Acanthamoeba triangularis

Acanthamoeba, a genus that contains at least 24 species of free-living protozoa, is ubiquitous in nature. Successful treatment of Acanthamoeba infections is always very difficult and not always effective. More effective drugs must be developed, and medicinal plants may have a pivotal part in the future of drug discovery. Our research focused on investigating the in vitro anti- acanthamoebic potential of Leea indica and its constituent gallic acid in different concentrations. Water and butanol fractions exhibited significant amoebicidal activity against trophozoites and cysts. Gallic acid (100 µg/mL) revealed 83% inhibition of trophozoites and 69% inhibition of cysts. The butanol fraction induced apoptosis in trophozoites, which was observed using tunnel assay. The cytotoxicity of the fractions and gallic acid was investigated against MRC-5 and no adverse effects were observed. Gallic acid was successfully loaded within poly (D,L-lactide-co-glycolide) (PLGA) nanoparticles with 82.86% encapsulation efficiency, while gallic acid showed 98.24% in vitro release at 48 hours. Moreover, the gallic acid encapsulated in the PLGA nanoparticles exhibited 90% inhibition against trophozoites. In addition, gallic acid encapsulated nanoparticles showed reduced cytotoxicity towards MRC-5 compared to gallic acid, which evidenced that natural product nanoencapsulation in polymeric nanoparticles could play an important role in the delivery of natural products.

Promoted Antitumor Activity of Myricetin against Lung Carcinoma Via Nanoencapsulated Phospholipid Complex in Respirable Microparticles

PURPOSE

Myricetin (MYR) flavonoid is well-recognized for its antioxidant, anti-inflammatory and anti-tumor potential. Introducing nanomedicine was the ultimate resort to solve the imperfections of this nutraceutical, namely solubility, stability and delivery issues. The study, thus, aims at developing inhalable microparticles comprising MYR solid lipid nanoparticles (SLNs) for lung cancer therapy.

METHODS

A two-step preparation procedure starting with complexation of MYR with the phospholipid Lipoid-S100, followed by nanoencapsulation in Gelucire-based, surfactant-free SLNs was developed. SLNs were characterized in terms of physicochemical properties, MYR loading, release behavior as well as anti-tumor potential and cellular uptake. Respirable microparticles were then obtained by spray drying SLNs with carbohydrate carriers. Their size, flowability and pulmonary deposition pattern were assessed.

RESULTS

Optimized SLNs were 75.98 nm in diameter with a zeta-potential of -22.5 mV, and an encapsulation efficiency of 84.5%. Attempts to ameliorate drug loading implicate MYR-phospholipid complexation (MYR-PH-CPX) prior to its entrapment in SLNs, which ensured 5-fold increase in drug loading. Viability assays were modified to guarantee MYR chemical stability. Superior antitumor activity of MYR-phospholipid-complex and 3-fold reduction in IC₅₀ were accomplished with MYR-SLNs. This could be related to enhanced cellular uptake revealed by confocal imaging and doubled fluorescence intensity. SLNs entrapping MYR-PH-CPX were spray-dried with carbohydrate carriers to produce respirable microparticles. The latter ensured MMAD of 2.39 μm and span index of 1.84, in addition to good flowability and > 80% release over 8 h. Deposition experiments revealed MMAD of 2.77 μm, FPF of 81.23 and EF of 93% indicating particle deposition in the targeted bronchial region.

CONCLUSIONS

The study highlights the ability of phospholipid-complex on the nanoencapsulation, cellular uptake and antitumor activity of MYR. Formulation of respirable microparticles gives promises of efficacious therapy of lung carcinoma.

Breast intraductal nanoformulations for treating ductal carcinoma in situ I: Exploring metal-ion complexation to slow ciclopirox release, enhance mammary persistence and efficacy

INTRODUCTION

Ductal Carcinoma In Situ (DCIS) represents a significant fraction (~20-25%) of all newly diagnosed breast cancer cases and, if left untreated, a significant fraction of patients will progress to invasive disease. Surgery is the only treatment option. Ciclopirox (CPX), an FDA-approved antifungal drug, has exhibited promising antitumor activity by down-regulating the expression of vital antiapoptotic cellular proteins and inhibiting the genetic expression of several oncogenic pathways. In this study, the feasibility of using nanoscale delivery systems to control release and prolong mammary tissue persistence of a lipophilic metal complex of CPX and Zinc (CPXZn) after intraductal administration was investigated.

METHODS

CPX and CPX-Zn nanosuspensions (NSs) were prepared using an evaporative nanoprecipitation-ultra-sonication method. Flash nanoprecipitation was used to prepare PLGA nanoparticles (NPs) loaded with CPXZn. Our established orthotopic DCIS rat model was used to evaluate efficacy. Briefly, two days after 13762 Mat B III cell intraductal inoculation, rats were divided into treatment groups and a single intraductal injection of CPX NS, CPX-Zn NS or CPX-Zn NPs was administered. In the first study arm, the efficacy of CPX NS (1, 3, 5 mg/duct) was evaluated. In the second arm, the in vivo efficacy of CPX NS, CPX-Zn NS and CPX-Zn loaded NPs was evaluated and compared at equivalent CPX doses. The mammary persistence of CPX from CPX NS, CPX-Zn NS, and CPX-Zn PLGA NPs was also assessed.

RESULTS

CPX-Zn complex was successfully synthesized and characterized by several spectral analyses. CPX release was slowed from the CPX-Zn NS and further slowed by incorporating CPX-Zn into PLGA NPs as compared to the CPX NS with release half times following the order: CPX NS < CPX-Zn NS << CPX-Zn NP. Intraductal CPX NS administration was dose and time dependent in suppressing tumor initiation suggesting prolonged mammary exposure may improve efficacy. In the second arm, mammary tissue persistence of CPX followed the rank order CPX NS < CPX-Zn NS << CPX-Zn NP at 6 h and 48 h post-administration. Prolonged mammary CPX exposure was highly correlated to improved efficacy. Prolonged CPX tissue persistence, attributed to slower release from the zinc complex and the PLGA NPs, resulted in a 5-fold dose reduction compared to the CPX NS.

CONCLUSIONS

The current results demonstrate that slowing drug release in the mammary duct after intraductal administration overcomes the rapid ductal clearance of CPX, prolongs mammary tissue persistence, improves efficacy against DCIS lesions in vivo, and requires 5-fold less CPX to achieve equivalent efficacy. The studies also provide a strategic path forward for developing a locally administered drug delivery system for treating DCIS, for which no primary chemotherapy option is available.

In vitro Antifungal Activity of Olive (Olea europaea) Leaf Extracts Loaded in Chitosan Nanoparticles

Olive leaf extract is characterized by a high content of phenols and flavonoids (oleuropein, luteolin, and their derivatives). These compounds are defined as secondary metabolites and exert such as anti-inflammatory, antioxidant, and antimicrobial activities. We investigated the in vitro antifungal activity of two olive leaf extracts (named EF1 and EF2) against a Fusarium proliferatum (AACC0215) strain that causes diseases to many economically important plants and synthesizing diverse mycotoxins. In this work, we aimed to identify the most appropriate concentration between the tested two olive leaf extracts to develop a safe, stable and efficient drug delivery system. Qualitative and quantitative analyses of the two olive leaf extracts by (HPLC) were performed. Furthermore, we also evaluated the antifungal effects of the two leaf extracts when encapsulated in chitosan-tripolyphosphate nanoparticles. The major compound in both EF1 and EF2 was oleuropein, with 336 and 603 mg/g, respectively, however, high concentrations of flavonoid were also present. EF1 and EF2 showed a concentration depended effect on F. proliferatum (AACC0215) viability. Our results showed a great efficacy of EF1/nanoparticles at the higher concentration tested (12X) against the target species. In this case, we observed an inhibition rate to both germination and growth of 87.96 and 58.13%, respectively. We suggest that EF1 olive leaf extracts, as free or encapsulated in chitosan-tripolyphosphate nanoparticles, could be used as fungicides to control plant diseases. Finally, future application of these findings may allow to reduce the dosage of fungicides potentially harmful to human health.

Investigations of the Influences of Processing Conditions on the Properties of Spray Dried Chitosan-Tripolyphosphate Particles loaded with Theophylline

The preparation of chitosan-tripolyphosphate (chitosan-TPP) particles by the spray drying had been reported word widely for a sustained release of drugs to prevent rapid drug metabolism. Although the spray drying is a straightforward procedure turning a liquid feed into a well-defined dry powder, seldom research works were focusing on how the processing parameters and liquid feeding constitutions of spray drying system might affect the properties of spray-dried chitosan particles loaded with drugs, such as the particle size and morphologies, which would be very important to drug encapsulation and dissolution of the drug delivery design. This study thus prepared the chitosan particles with theophylline (TH) loaded as a model drug and TPP as cross-linker at various spray drying conditions. Our results indicate the diameter of the TH/chitosan-TPP particles made by customized spray drying apparatus spans from 424 to 497 nm with a geometric standard deviation of less than 2. The corresponding release of TH was tunable by the chitosan-TPP matrix density under the selected spray drying temperature and the carrying air flow rate. These results suggest an indeed need for optimized spray drying processing conditions to make the ideal spray-dried TH/chitosan-TPP particles for the desired drug delivery.

Preparation of Chitosan-Hexaconazole Nanoparticles as Fungicide Nanodelivery System for Combating Ganoderma Disease in Oil Palm

Fungicide is used to control fungal disease by destroying and inhibiting the fungus or fungal spores that cause the disease. However, failure to deliver fungicide to the disease region leads to ineffectiveness in the disease control. Hence, in the present study, nanotechnology has enabled the fungicide active agents (hexaconazole) to be encapsulated into chitosan nanoparticles with the aim of developing a fungicide nanodelivery system that can transport them more effectively to the target cells (Ganoderma fungus). A pathogenic fungus, Ganoderma boninense (G. boninense), is destructive to oil palm whereby it can cause significant loss to oil palm plantations located in the Southeast Asian countries, especially Malaysia and Indonesia. In regard to this matter, a series of chitosan nanoparticles loaded with the fungicide, hexaconazole, was prepared using various concentrations of crosslinking agent sodium tripolyphosphate (TPP). The resulting particle size revealed that the increase of the TPP concentration produced smaller particles. In addition, the in vitro fungicide released at pH 5.5 demonstrated that the fungicide from the nanoparticles was released in a sustainable manner with a prolonged release time up to 86 h. On another note, the in vitro antifungal studies established that smaller particle size leads to lower half maximum effective concentration (EC₅₀) value, which indicates higher antifungal activity against G. boninense.

Hydrogel Nanofibers from Carboxymethyl Sago Pulp and Its Controlled Release Studies as a Methylene Blue Drug Carrier

The potential use of carboxymethyl sago pulp (CMSP) extracted from sago waste for producing hydrogel nanofibers was investigated as a methylene blue drug carrier. Sago pulp was chemically modified via carboxymethylation reaction to form carboxymethyl sago pulp (CMSP) and subsequently used to produce nanofibers using the electrospinning method with the addition of poly(ethylene oxide) (PEO). The CMSP nanofibers were further treated with citric acid to form cross-linked hydrogel. Studies on the percentage of swelling following the variation of citric acid concentrations and curing temperature showed that 89.20 ± 0.42% of methylene blue (MB) was loaded onto CMSP hydrogel nanofibers with the percentage of swelling 4366 ± 975%. Meanwhile, methylene blue controlled release studies revealed that the diffusion of methylene blue was influenced by the pH of buffer solution with 19.44% of MB released at pH 7.34 within 48 h indicating the potential of CMSP hydrogel nanofibers to be used as a drug carrier for MB.

Faster Release of Lumen-Loaded Drugs than Matrix-Loaded Equivalent in Polylactic Acid/Halloysite Nanotubes

Nanocomposite-based drug delivery systems with intrinsic controlled release properties are of great interest in biomedical applications. We report a novel polylactic acid (PLA)/halloysite nanotube (HNT) nanocomposite-based drug delivery system. PLA/HNT nanocomposites have shown immense potential for use in biomedical applications due to their favorable cyto- and hemo-compatibility. The objective of this study was to evaluate the release of active pharmaceutical ingredients (API) from PLA/HNT composites matrix and the effect of preloading the API into the lumen of the HNT on its release profile. Aspirin was used in this study as a model drug as it is a common nonsteroidal anti-inflammatory and antiplatelet agent widely used for various medical conditions. These two types of drug-loaded PLA/HNT nanocomposites were characterised by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR), surface wettability and mechanical testing. Statistical analysis was conducted on numerical data. Drug entrapment and in vitro drug release studies were conducted using UV spectrophotometry. Results indicate that aspirin was successfully loaded into the lumen of HNT, which resulted in the sustained release of aspirin from the nanocomposites. Furthermore, the addition of HNT into the polymer matrix increased the mechanical properties, indicating its suitability as a drug-eluting reinforcing agent.

A Potent Antifungal Agent for Basal Stem Rot Disease Treatment in Oil Palms Based on Chitosan-Dazomet Nanoparticles

The use of nanotechnology could play a significant role in the agriculture sector, especially in the preparation of new-generation agronanochemicals. Currently, the economically important plant of Malaysia, the oil palm, faces the threat of a devastating disease which is particularly caused by a pathogenic fungus, Ganoderma boninense. For the development of an effective antifungal agent, a series of chitosan nanoparticles loaded with a fumigant, dazomet, were prepared using various concentrations of sodium tripolyphosphate (TPP)—2.5, 5, 10, and 20 mg/mL, abbreviated as CDEN2.5, CDEN5, CDEN10, and CDEN20, respectively. The effect of TPP as a crosslinking agent on the resulting particle size of the synthesized nanoparticles was investigated using a particle size analyzer and high-resolution transmission electron microscopy (HRTEM). Both methods confirmed that increasing the TPP concentration resulted in smaller particles. In addition, in vitro fumigant release at pH 5.5 showed that the release of the fumigant from the nanoparticles was of a sustained manner, with a prolonged release time up to 24 h. Furthermore, the relationship between the chitosan-dazomet nanoparticles and the in vitro antifungal activity against G. boninense was also explored, where the nanoparticles of the smallest size, CDEN20, gave the highest antifungal efficacy with the lowest half maximum effective concentration (EC₅₀) value of 13.7 ± 1.76 ppb. This indicates that the smaller-sized agronanoparticles were more effective as an antifungal agent. The size can be altered, which plays a crucial role in combatting the Ganoderma disease. The agronanoparticles have controlled release properties and high antifungal efficacy on G. boninense, thus making them a promising candidate to be applied in the field for Ganoderma treatment.

Establishing an osteoimmunomodulatory coating loaded with aspirin on the surface of titanium primed with phase-transited lysozyme

BACKGROUND

To improve osseointegration and enhance the success rate of implanted biomaterials, the surface modification technology of bone implants has developed rapidly. Intensive research on osteoimmunomodulation has shown that the surfaces of implants should possess favorable osteoimmunomodulation to facilitate osteogenesis.

METHODS

A novel, green and efficient phase-transited lysozyme (PTL) technique was used to prime titanium discs with a positive charge. In addition, sodium hyaluronate (HA) and self-assembled type I collagen containing aspirin (ASA) nanoparticles were decorated on PTL-primed Ti discs via electrostatic interaction.

RESULTS

The behaviors of bone marrow stromal cells (BMSCs) on the Ti disc surfaces containing ASA were analyzed in different conditioned media (CM) generated by macrophages. Additionally, the secretion of inflammation-related cytokines of macrophages on the surfaces of different Ti discs was investigated in in vitro experiments, which showed that the Ti surface containing ASA not only supported the migration, proliferation and differentiation of BMSCs but also reduced the inflammatory response of macrophages compared with Ti discs without surface modification. After implantation in vivo, the ASA-modified implant can significantly contribute to bone formation around the implant, which mirrors the evaluation in vitro.

CONCLUSION

This study highlights the significant effects of appropriate surface characteristics on the regulation of osteogenesis and osteoimmunomodulation around an implant. Implant modification with ASA potentially provides superior strategies for the surface modification of biomaterials.

Synthesis and Optimization of Chitosan Nanoparticles Loaded with L-Ascorbic Acid and Thymoquinone

The combination of compounds with different classes (hydrophobic and hydrophilic characters) in single chitosan carrier is a challenge due to the hydrophilicity of chitosan. Utilization of l-ascorbic acid (LAA) and thymoquinone (TQ) compounds as effective antioxidants is marred by poor bioavailability and uptake. Nanoparticles (NPs) solved the problem by functioning as a carrier for them because they have high surface areas for more efficient delivery and uptake by cells. This research, therefore, synthesized chitosan NPs (CNPs) containing LAA and TQ, CNP-LAA-TQ via ionic gelation routes as the preparation is non-toxic. They were characterized using electron microscopy, zetasizer, UV⁻VIS spectrophotometry, and infrared spectroscopy. The optimum CNP-LAA-TQ size produced was 141.5 ± 7.8 nm, with a polydispersity index (PDI) of 0.207 ± 0.013. The encapsulation efficiency of CNP-LAA-TQ was 22.8 ± 3.2% for LAA and 35.6 ± 3.6% for TQ. Combined hydrophilic LAA and hydrophobic TQ proved that a myriad of highly efficacious compounds with poor systemic uptake could be encapsulated together in NP systems to increase their pharmaceutical efficiency, indirectly contributing to the advancement of medical and pharmaceutical sectors.

Guided bone regeneration with asymmetric collagen-chitosan membranes containing aspirin-loaded chitosan nanoparticles

Introduction

Membranes allowing the sustained release of drugs that can achieve cell adhesion are very promising for guided bone regeneration. Previous studies have suggested that aspirin has the potential to promote bone regeneration. The purpose of this study was to prepare a local drug delivery system with aspirin-loaded chitosan nanoparticles (ACS) contained in an asymmetric collagen-chitosan membrane (CCM).

Methods

In this study, the ACS were fabricated using different concentrations of aspirin (5 mg, 25 mg, 50 mg, and 75 mg). The drug release behavior of ACS was studied. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to examine the micromorphology of ACS and aspirin-loaded chitosan nanoparticles contained in chitosan-collagen membranes (ACS-CCM). In vitro bone mesenchymal stem cells (BMSCs) were cultured and critical-sized cranial defects on Sprague-Dawley rats were made to evaluate the effect of the ACS-CCM on bone regeneration.

Results

Drug release behavior results of ACS showed that the nanoparticles fabricated in this study could successfully sustain the release of the drug. TEM showed the morphology of the nanoparticles. SEM images indicated that the asymmetric membrane comprised a loose collagen layer and a dense chitosan layer. In vitro studies showed that ACS-CCM could promote the proliferation of BMSCs, and that the degree of differentiated BMSCs seeded on CCMs containing 50 mg of ACS was higher than that of other membranes. Micro-computed tomography showed that 50 mg of ACS-CCM resulted in enhanced bone regeneration compared with the control group.

Conclusion

This study shows that the ACS-CCM would allow the sustained release of aspirin and have further osteogenic potential. This membrane is a promising therapeutic approach to guiding bone regeneration.

Thermosensitive Chitosan Hydrogels Containing Polymeric Microspheres for Vaginal Drug Delivery

Thermosensitive hydrogels have increasingly received considerable attention for local drug delivery based on many advantages. However, burst release of drugs is becoming a critical challenge when the hydrogels are employed. Microspheres- (MS-) loaded thermosensitive hydrogels were thus fabricated to address this limitation. Employing an orthogonal design, the spray-dried operations of tenofovir (TFV)/Bletilla striata polysaccharide (BSP)/chitosan (CTS) MS were optimized according to the drug loading (DL). The physicochemical properties of the optimal MS (MS F) were characterized. Depending on the gelation temperature and gelating time, the optimal CTS-sodium alginate- (SA-) α,β-glycerophosphate (GP) (CTS-SA-GP) hydrogel was obtained. Observed by scanning electron microscope (SEM), TFV/BSP/CTS MS were successfully encapsulated in CTS-SA-GP. In vitro releasing demonstrated that MS F-CTS-SA-GP retained desirable in vitro sustained-release characteristics as a vaginal delivery system. Bioadhesion measurement showed that MS-CTS-SA-GP exhibited the highest mucoadhesive strength. Collectively, MS-CTS-SA-GP holds great promise for topical applications as a sustained-release vaginal drug delivery system.

Doxorubicin-Incorporated Nanotherapeutic Delivery System Based on Gelatin-Coated Gold Nanoparticles: Formulation, Drug Release, and Multimodal Imaging of Cellular Internalization

In this work, we developed a new pH- and temperature-responsive nanochemotherapeutic system based on Doxorubicin (DOX) noncovalently bound to biosynthesized gelatin-coated gold nanoparticles (DOX-AuNPs@gelatin). The real-time release profile of DOX was evaluated at different pH values (7.4, 5.3, and 4.6) and temperatures (22-45 °C) in aqueous solutions, and its therapeutic performance was examined in vitro against MCF-7 breast cancer cells. TEM, dark-field scattering, and wide-field fluorescence microscopy indicated the effective uptake of nanochemotherapeutics with the subsequent release and progressive accumulation of DOX in cell nuclei. MTT assays clearly showed the effectiveness of the treatment by inhibiting the growth of MCF-7 breast cancer cells for a loaded drug concentration of 5 μg/mL. The most informative data about the dynamic release and localization were provided by scanning confocal microscopy using time-resolved fluorescence and surface-enhanced Raman scattering (SERS) techniques. In particular, fluorescence-lifetime imaging (FLIM) recorded under 485 nm pulsed diode laser excitation revealed the bimodal distribution of DOX in cells. The shorter fluorescence lifetime of DOX localized in nuclei (1.52 ns) than in the cytoplasm (2.4 ns) is consistent with the cytotoxic mechanism induced by DOX-DNA intercalation. Remarkably, the few DOX molecules captured between nanoparticles ("electromagnetic hotspots") after most drug is released act as SERS reporters for the localization of plasmonic nanocarriers in MCF-7 cells. The high drug loading capacity and effective drug release under pH control combined with the advantage of multimodal visualization inside cells clearly indicate the high potential of our DOX-AuNPs@gelatin delivery system for implementation in nanomedicine.