Development of antifungal fibrous ocular insert using freeze-drying technique.

Candida species is one of the pathogenic fungi of the eye responsible for keratitis that frequently causes vision impairment and blindness. Effective treatment requires long-term use of antifungal drugs, which is opposed by the defensive mechanisms of the eye and inadequate corneal penetration. The objective of this study was to develop a carrier for prolonged ocular application of fluconazole (FLZ) to treat keratitis. FLZ was encapsulated into chitosan fibrous matrices (F1-F4) using different chitosan concentrations (0.02, 0.1, 0.5, and 1%w/v, respectively) by freeze-drying as a single-step technique. Studying the morphology and surface properties of the inserts revealed a porous matrix with fibrous features with a large surface area. Thermal stability and chemical compatibility were confirmed by DSC/TGA/DTA and FT-IR, respectively. Loading capacity (LC) and entrapment efficiency (EE) were determined. According to the in vitro release study, F4 (0.11 mg mg-1 LC and 87.53% EE) was selected as the optimum insert because it had the most sustained release, with 15.85% burst release followed by 75.62% release within 12 h. Ex vivo corneal permeation study revealed a 1.2-fold increase in FLZ permeation from F4 compared to FLZ aqueous solution. Also, in the in vivo pharmacokinetic study in rabbits, F4 increased the AUC0-8 of FLZ by 9.3-fold and its concentration in aqueous humor was maintained above the MIC through the experimentation time. Studies on cytotoxicity (MTT assay) provide evidence for the safety and biocompatibility of F4. Therefore, the freeze-dried FLZ-loaded chitosan fibrous insert could be a promising candidate for treating ocular keratitis.

Recent Advances in Nano-Based Drug Delivery Systems for Treatment of Liver Cancer.

Liver cancer is one of the aggressive primary tumors as evident by high rate of incidence and mortality. Conventional treatments (e.g. chemotherapy) suffer from various drawbacks including wide drug distribution, low localized drug concentration, and severe off-site toxicity. Therefore, they cannot satisfy the mounting need for safe and efficient cancer therapeutics, and alternative novel strategies are needed. Nano-based drug delivery systems (NDDSs) are among these novel approaches that can improve the overall therapeutic outcomes. NDDSs are designed to encapsulate drug molecules and target them specifically to liver cancer. Thus, NDDSs can selectively deliver therapeutic agents to the tumor cells and avoid distribution to off-target sites which should improve the safety profile of the active agents. Nonetheless, NDDSs should be well designed, in terms of the preparing materials, nanocarriers structure, and the targeting strategy, in order to accomplish these objectives. This review discusses the latest advances of NDDSs for cancer therapy with emphasis on the aforementioned essential design components. The review also entails the challenges associated with the clinical translation of NDDSs, and the future perspectives towards next-generation NDDSs.

Exogenous and endogenous nitric oxide eluting polylactic acid-based nanofibrous scaffolds for enhancing angiogenesis of diabetic wounds.

Delayed wound healing is a major complication that diabetic patients suffer from due to high microbial infection susceptibility, high diabetic wound alkalinity, a low lymphangiogenesis rate, and a high inflammation rate, resulting in severe gangrene. Hence, this study aims to develop a multifunctional adhesive nanofibrous patch to promote the wound healing process. Phenytoin, sildenafil citrate, and/or nitric oxide-eluting nanoparticles were incorporated separately within the polylactic acid nanofibrous layer. Polylactic acid was fabricated in the form of highly porous nanofibrous matrices that resemble the natural structure of skin tissues in order to act as scaffolds that help cell migration and proliferation. A polylactic acid nanofibrous layer incorporating phenytoin was designed to stimulate fibroblast proliferation and inhibit inflammation. Another polylactic acid nanofibrous layer was loaded either with nitric oxide-eluting nanoparticles or sildenafil as a pro-angiogenic layer that can supply tissues with nitric oxide gas either exogenously or endogenously, respectively. The developed nanofibrous layers were in-vitro evaluated through different physicochemical, mechanical, and biological approaches. Finally, the efficiency of the prepared single multilayered patch was tested using an in-vivo alloxan-induced diabetic rats' model, which proved that the patches were able to release the incorporated cargos in a controlled manner, enhancing the wound healing process.

Microporation-Mediated Transdermal Delivery of In Situ Gel Incorporating Etodolac-Loaded PLGA Nanoparticles for Management of Rheumatoid Arthritis.

Management of rheumatoid arthritis (RA) requires long-term administration of different medications since there has been no cure until now. Etodolac (ETD) is a nonsteroidal anti-inflammatory drug commonly used for RA management. However, its long-term administration resulted in severe side effects. This study aimed to develop a transdermal in situ gel incorporating ETD-loaded polymeric nanoparticles (NPs) to target the affected joints for long-term management of RA. Several PLGA NPs incorporating 1% ETD were prepared by nanoprecipitation and optimized according to the central composite design. The optimum NPs (F1) exhibited 96.19 ± 2.31% EE, 282.3 ± 0.62 nm PS, 0.383 ± 0.04 PDI, and -6.44 ± 1.69 ZP. A hyaluronate coating was applied to F1 (H-F1) to target activated macrophages at inflammation sites. H-F1 exhibited 287.4 ± 4.2 nm PS, 0.267 ± 0.02 PDI, and -23.7 ± 3.77 ZP. Pluronic F-127 in situ gel (H-F1G) showed complete gelation at 29 °C within 5 min. ETD permeation from H-F1G was sustained over 48 h when applied to microporated skin and exhibited significant enhancement of all permeation parameters. Topical application of H-F1G (equivalent to 8 mg ETD) to Wistarrat microporated skin every 48 h resulted in antirheumatic therapeutic efficacy comparable to commercial oral tablets (10 mg/kg/day).

Dual antituberculosis drugs-loaded gelatin hydrogel bioimplant for treating spinal tuberculosis.

Spinal tuberculosis (TB) represents around 1% of the recorded TB with a high mortality rate due to neurological complications and kyphosis. The current work aimed to develop a bioimplant scaffold to treat spinal TB disease. The scaffold is composed of a biocompatible semi-interpenetrating (semi-IPN) gelatin-based hydrogel incorporating mesoporous silica nanoparticles (MPS-NPs) loaded with rifampicin (RIF) and levofloxacin (LEV) to treat TB. The elastic modulus of the hydrogel was 7.18 ± 0.78 MPa. Minimum inhibitory concentrations (MIC) value against Mycobacterium bovis for LEV-loaded and RIF-loaded MPS-NPs were 6.50 and 1.33 µm/ml, respectively.Sequential release of drugs was observed after 15 days. Loading of the MPS-NPs in the hydrogel matrix governed the amount of released drugs by prolonging the period of release up to 60 days. WST-1 test confirmed the biocompatibility and safety of the developed vertebral hydrogel bioimplant. Histological and immunohistochemistry micrographs showed the progress in healing process with the bioimplant. Besides, loading of LEV and RIF in the implants declined the presence of the giant macrophages clusters as compared to control groups. All the obtained results support the potential use of the developed vertebral hydrogel bioimplant as a scaffold with good mechanical and biocompatible properties along with a good ability to eradicate the TB pathogen.

Fortified gelatin-based hydrogel scaffold with simvastatin-mixed nanomicelles and platelet rich plasma as a promising bioimplant for tissue regeneration.

Treatment of intervertebral disc (IVD) degeneration includes conservative and surgical strategies that have a high risk of recurrence. Consequently, tissue engineering represents a promising alternative treatment. This study aimed at healing damaged IVD with a bioimplant that can maintain the function of defected IVD. The developed IVD scaffold is composed of a fortified biocompatible gelatin-based hydrogel to mimic the ECM mechanical properties of IVD and to allow a sustained release of loaded bioactive agents. The hydrogel is laden with platelet-rich plasma (PRP) and simvastatin (SIM)-loaded mixed pluronics nanomicelles because of their regenerative ability and anti-inflammatory effect, respectively. The gelatin-based hydrogel attained swelling of 508.9 ± 7.9 % to 543.1 ± 5.9 % after 24 h. Increasing crosslinking degree of the hydrogel improved its mechanical elasticity up to 0.3 ± 0.1 N/mm2, and retarded its degradation. The optimum mixed nanomicelles had particle size of 84 ± 0.5 nm, a surface charge of -10 ± 7.1 mv, EE% of 84.9 %, and released 88.4 % of SIM after 21 days. Cytotoxicity of IVD components was evaluated using human skin fibroblast for 3 days. WST-test results proved biocompatibility of IVD scaffold. Subcutaneous implantation of the IVD scaffold was performed for 28 days to test in-vivo biocompatibility. Histological and histochemical micrographs depicted normal healing signs such as macrophages, T-cells, angiogenesis and granulation reactions. Introducing PRP in IVD improved healing process and decreased inflammation reactions. The developed multicomponent implant could be used as potential IVD scaffold with desirable mechanical properties, biocompatibility and healing process.

Design, development, in-vitro and in-vivo evaluation of polylactic acid-based multifunctional nanofibrous patches for efficient healing of diabetic wounds.

Impaired healing of diabetic ulcers is one of the major complications of diabetic patients due to high susceptibility to microbial infections, impaired lymphianogenesis, edema, and consequently impairing proper healing. This could even lead to much worse complications that include severe gangrene, trauma and finally limb amputation. Therefore, this study aims to develop a multilayered durable nanofibrous wound patch loaded with three promising drugs (phenytoin, sildenafil citrate and simvastatin) each in a separate layer to target a different wound healing phase. Polylactic acid was used for the preparation of the nanofibrous matrix of the wound patch, where each drug was incorporated in a separate layer during the preparation process. Drugs release profiles were studied over 3 weeks. Results showed that both phenytoin and simvastatin were released within 14 days while sildenafil continued till 21 days. Both physicochemical and mechanical characteristics of the patches were fully assessed as well as their biodegradability, swellability, breathability and porosity. Results showed that incorporation of drugs preserved the physicochemical and mechanical properties as well as porosity of the developed nanofibers. In addition, patches were evaluated for their biocompatibility and cell adhesion capability before being tested through in-vivo diabetic wound rat model induced by alloxan for three weeks. In vivo results showed that the patches were successful in inducing proper wound healing in diabetic rat model with overcoming the above-mentioned obstacles within 3 weeks. This was confirmed through assessing wound closure as well as from histopathological studies that showed complete healing with proper cell regeneration and arrangement without forming scars.

3D-bioimplants mimicking the structure and function of spine units for the treatment of spinal tuberculosis.

Approximately 1-2% of the reported tuberculosis (TB) cases have skeletal system problems, particularly spinal TB. The complications of spinal TB involve the destruction of vertebral body (VB) and intervertebral disc (IVD) which consequently leads to kyphosis. This work aimed at utilizing different technologies to develop, for the first time, a functional spine unit (FSU) replacement to mimic the structure and function of the VB and IVD along with a good ability to treat spinal TB. 3D-printed scaffolds with different porous patterns (hexagonal or grid) were fabricated from biocompatible acrylonitrile butadiene styrene, and polylactic acid to replace damaged VB and IVD, respectively. The VB scaffold is filled with gelatine-based semi-IPN hydrogel containing mesoporous silica nanoparticles loaded with two antibiotics, rifampicin and levofloxacin, to act against TB. The IVD scaffold incorporates a gelatin hydrogel loaded with regenerative platelet-rich plasma and anti-inflammatory simvastatin-loaded mixed nanomicelles. The obtained results confirmed the superior mechanical strength of both 3D-printed scaffolds and loaded hydrogels as compared to normal bone and IVD with high in vitro (cell proliferation, anti-inflammation and anti-TB), and in vivo biocompatibility profiles. Moreover, the custom-designed replacements have achieved the expected prolonged release of antibiotics up to 60 days. Given the promising study findings, the utilization of the developed drug-eluting scaffold system can be extrapolated to treat not only spinal TB but also to resolve diverse backbone/spine problems that need a critical surgical process including degenerative IVD and its consequences like atherosclerosis, sliding or spondylolisthesis and severe traumatic bone fracture.

Assessment of the Anticancer Potentials of the Free and Metal-Organic Framework (UiO-66) - Delivered Phycocyanobilin.

Phycocyanin (C-PC) is a constitutive chromoprotein of Arthrospira platensis, which exhibits promising efficacy against different types of cancer. In this study, we cleaved C-PC's chromophore phycocyanobilin (PCB) and demonstrated its ability as an anti-cancer drug for Colorectal cancer (CRC). PCB displayed an anti-cancer effect for CRC (HT-29) cells with IC50 of 108 µg/ml. Assessing the transcripts levels of some biomarkers revealed that the PCB caused an upregulation in the anti-metastatic gene NME1 level and downregulation of the COX-2 level. The flow cytometric results showed the effect of PCB on the arrest of the cell cycle's G1 phase. In addition, we successfully synthesized the UiO-66 (Zr-MOF). We incorporated the PCB into UiO-66 nanoparticles with a loading percentage of 46 %. Assessment of the cytotoxic effects of UiO-66@PCB showed a 2-fold improvement in the IC50 compared to the free PCB. In conclusion, we have shown that PCB displayed a promising potential as an anti-cancer agent. Yet, it is considered a safe and natural substance that can help to mitigate cancer spread and symptoms. In the meantime, UiO-66 can be used as a safe nano-delivery tool for PCB.

Propranolol-Loaded Trehalosome as Antiproliferative Agent for Treating Skin Cancer: Optimization, Cytotoxicity, and In Silico Studies.

This study aims at preparing propranolol-loaded trehalosomes (a trehalose-coated liposome) to be used as an antiproliferative agent for treating skin cancer. A factorial design was used to select the optimum formula, where trehalose, lecithin, and Tween 80 levels were studied. A total of 24 runs were prepared and characterized according to size, charge, entrapment efficiency, and release after 3 h to select the optimum formula. The optimized formula was investigated using TEM, DSC, and FTIR. Cell studies were carried out against the human melanoma cell line to measure cytotoxicity, apoptosis/necrosis, and cell cycle arrest. In silico studies were conducted to understand the interaction between propranolol and the influential receptors in melanoma. The results showed the selected formula consisted of trehalose (175 mg), lecithin (164 mg), and Tween 80 (200 mg) with a size of 245 nm, a charge of -9 mV, an EE% of 68%, and a Q3 of 62%. Moreover, the selected formula has good cytotoxicity compared to the free drug due to the synergistic effect of the drug and the designed carrier. IC50 of free propranolol and the encapsulation of propranolol were 17.48 µg/mL and 7.26 µg/mL, respectively. Also, propranolol and the encapsulation of propranolol were found to significantly increase early and late apoptosis, in addition to inducing G1 phase cell cycle arrest. An in silico virtual study demonstrated that the highest influential receptors in melanoma were the vitamin D receptor, CRH-R1, VEGFR 1, and c-Kit, which matches the results of experimental apoptotic and cell cycle analysis. In conclusion, the selected formula has good cytotoxicity compared to the free drug due to the synergistic effect of the drug and the designed carrier, which make it a good candidate as an antiproliferative agent for treating skin cancer.

Layer-by-layer development of chitosan/alginate-based platelet-mimicking nanocapsules for augmenting doxorubicin cytotoxicity against breast cancer.

Breast carcinoma is considered one of the most invasive and life-threatening malignancies in females. Mastectomy, radiation therapy, hormone therapy and chemotherapy are the most common treatment choices for breast cancer. Doxorubicin (DOX) is one of the most regularly utilized medications in breast cancer protocols. However, DOX has showed numerous side effects including lethal cardiotoxicity. This study aims to fortify DOX cytotoxicity and lowering its side effects via its combining with the antidiabetic metformin (MET) as an adjuvant therapy, along with its effective delivery using natural platelet-rich plasma (PRP), and newly-developed PRP-mimicking nanocapsules (NCs). The PRP-mimicking NCs were fabricated via layer-by-layer (LBL) deposition of oppositely charged biodegradable and biocompatible chitosan (CS) and alginate (ALG) on a core of synthesized polystyrene nanoparticles (PS NPs) followed by removal of the PS core. Both natural PRP and PRP-mimicking NCs were loaded with DOX and MET adjuvant therapy, followed by their physicochemical characterizations including DLS, FTIR, DSC, and morphological evaluation using TEM. In-vitro drug release studies, cytotoxicity, apoptosis/necrosis, and cell cycle analysis were conducted using MCF-7 breast cancer cells. Also, an in-vivo assessment was carried out using EAC-bearing balb/c mice animal model to evaluate the effect of DOX/MET-loaded natural PRP and PRP-mimicked NCs on tumor weight, volume and growth biomarkers in addition to analyzing the immunohistopathology of the treated tissues. Results confirmed the development of CS/ALG-based PRP-mimicking NCs with a higher loading capacity of both drugs (DOX and MET) and smaller size (259.7 ± 19.3 nm) than natural PRP (489 ± 20.827 nm). Both in-vitro and in-vivo studies were in agreement and confirmed that MET synergized the anticancer activity of DOX against breast cancer. Besides, the developed LBL NCs successfully mimicked the PRP in improving the loaded drugs biological efficiency more than free drugs.

Ashwagandha-loaded nanocapsules improved the behavioral alterations, and blocked MAPK and induced Nrf2 signaling pathways in a hepatic encephalopathy rat model.

Ashwagandha (ASH), a vital herb in Ayurvedic medicine, demonstrated potent preclinical hepato- and neuroprotective effects. However, its efficacy is limited due to low oral bioavailability. Accordingly, we encapsulated ASH extract in chitosan-alginate bipolymeric nanocapsules (ASH-BPNCs) to enhance its physical stability and therapeutic effectiveness in the gastrointestinal tract. ASH-BPNC was prepared by emulsification followed by sonication. The NCs showed small particle size (< 220 nm), zeta-potential of 25.2 mV, relatively high entrapment efficiency (79%), physical stability at acidic and neutral pH, and in vitro release profile that extended over 48 h. ASH-BPNC was then investigated in a thioacetamide-induced hepatic encephalopathy (HE) rat model. Compared with free ASH, ASH-BPNC improved survival, neurological score, general motor activity, and cognitive task-performance. ASH-BPNC restored ALT, AST and ammonia serum levels, and maintained hepatic and brain architecture. ASH-BPNC also restored GSH, MDA, and glutathione synthetase levels, and Nrf2 and MAPK signaling pathways in liver and brain tissues. Moreover, ASH-BPNC downregulated hepatic NF-κB immunohistochemical expression. Moreover, the in vivo biodistribution studies demonstrated that most of the administered ASH-BPNC is accumulated in the brain and hepatic tissues. In conclusion, chitosan-alginate BPNCs enhanced the hepatoprotective and neuroprotective effects of ASH, thus providing a promising therapeutic approach for HE.

Hypericum perforatum L. Nanoemulsion Mitigates Cisplatin-Induced Chemobrain via Reducing Neurobehavioral Alterations, Oxidative Stress, Neuroinflammation, and Apoptosis in Adult Rats.

Cisplatin (Cis) is a potent chemotherapeutic agent; however, it is linked with oxidative stress, inflammation, and apoptosis, which may harmfully affect the brain. Hypericum perforatum L. (HP L.) is a strong medicinal plant, but its hydrophobic polyphenolic compounds limit its activity. Therefore, our study aimed to investigate the neuroprotective action of HP L. and its nanoemulsion (NE) against Cis-induced neurotoxicity. The prepared HP.NE was subjected to characterization. The droplet size distribution, surface charge, and morphology were evaluated. In addition, an in vitro dissolution study was conducted. Compared to Cis-intoxicated rats, HP L. and HP.NE-treated rats displayed improved motor activity and spatial working memory. They also showed an increase in their antioxidant defense system and a reduction in the levels of pro-inflammatory cytokines in the brain. Moreover, they showed an increase in the expression levels of the PON-3 and GPX genes, which are associated with a reduction in the brain levels of COX-2 and TP-53. These findings were confirmed by reducing the immunohistochemical expression of nuclear factor kappa (NF-ƘB) and enhanced Ki-67 levels. In conclusion, HP L. is a promising herb and could be used as an adjuvant candidate to ameliorate chemotherapeutic-induced neurotoxicity. Moreover, HP.NE has superior activity in lessening Cis-induced oxidative stress, inflammation, and apoptosis in brain tissue.

Aceclofenac/Citronellol Oil Nanoemulsion Repurposing Study: Formulation, In Vitro Characterization, and In Silico Evaluation of Their Antiproliferative and Pro-Apoptotic Activity against Melanoma Cell Line.

Aceclofenac (ACF) is a widely used non-steroidal anti-inflammatory drug (NSAID) known for its effectiveness in treating pain and inflammation. Recent studies have demonstrated that ACF possesses antiproliferative properties, inhibiting the growth of cancer cells in various cancer cell lines. Citronellol, a monoterpenoid alcohol found in essential oils, exhibits antioxidant properties and activities such as inhibiting cell growth and acetylcholinesterase inhibition. In this study, the objective was to formulate and evaluate an aceclofenac/citronellol oil nanoemulsion for its antiproliferative effects on melanoma. The optimal concentrations of citronellol oil, Tween 80, and Transcutol HP were determined using a pseudoternary phase diagram. The formulated nanoemulsions were characterized for droplet size, zeta potential, thermophysical stability, and in vitro release. The selected formula (F1) consisted of citronellol oil (1 gm%), Tween 80 (4 gm%), and Transcutol HP (1 gm%). F1 exhibited a spherical appearance with high drug content, small droplet size, and acceptable negative zeta potential. The amorphous state of the drug in the nanoemulsion was confirmed by Differential Scanning Calorimetry, while FTIR analysis indicated its homogenous solubility. The nanoemulsion showed significant antiproliferative activity, with a lower IC50 value compared to aceclofenac or citronellol alone. Flow cytometric analysis revealed cell cycle arrest and increased apoptosis induced by the nanoemulsion. In silico studies provided insights into the molecular mechanism underlying the observed antitumor activity. In conclusion, the developed aceclofenac/citronellol oil nanoemulsion exhibited potent cytotoxicity and pro-apoptotic effects, suggesting its potential as a repurposed antiproliferative agent for melanoma treatment. In a future plan, further animal model research for validation is suggested.

Development and Evaluation of Core-Shell Nanocarrier System for Enhancing the Cytotoxicity of Doxorubicin/Metformin Combination Against Breast Cancer Cell Line.

Breast cancer is the most invasive and life-threatening cancer in women. The treatment options are usually a combination of mastectomy, radiation therapy, hormonal therapy and chemotherapy. As a standard practice, doxorubicin (DOX) is one of the commonly used drugs for breast cancer treatment. However, DOX is known to have many harmful adverse effects including its cardiotoxicity. Hence, recent reports used metformin (MET), an anti-diabetic drug, as an adjuvant therapy to decrease the severity of DOX's adverse effects and to improve its ultimate therapeutic outcome. The current study is aimed at co-loading and enhancing the encapsulation efficiency of the hydrophilic DOX and MET in poly(lactic-co-glycolic acid) (PLGA) nanocapsules (NCs) with oil core for breast cancer treatment. The NCs were developed by single emulsification-solvent diffusion technique, and were optimized through using two types of oils, pluronics and PLGA (50:50) of different molecular weights followed by various physicochemical characterizations. The obtained DOX/MET-loaded NCs showed the size and polydispersity index (PDI) of 203.0 ± 3.4 nm and 0.081 ± 0.03, respectively with a surface charge of -2.15 ± 0.2 mV. The entrapment efficiency of DOX and MET were about 93.7% ± 2.9 and 70% ± 1.6, respectively. The developed PLGA core-shell NCs successfully sustained the DOX/MET release for more than 30 days. The in-vitro results showed a significant enhancement in DOX cytotoxic effect as well as a duplication in its apoptotic effect upon addition of MET for both free DOX/MET combination and DOX/MET-loaded PLGA NCs against MCF-7. Besides, flow cytometry demonstrated that the DOX/MET-loaded NCs possess their antitumor effect by preventing DNA replication and cell division. This study provides a promising facile, rapid and reproducible single emulsification-solvent diffusion technique for improving the encapsulation and release of hydrophilic drugs in nanocapsules for biomedical applications.

Repurposing of atorvastatin emulsomes as a topical antifungal agent.

Cutaneous fungal infection therapy confronts several issues concerning skin permeation in addition to drug resistance and adverse effects of conventional drugs. The repurposing strategy is supposed to overcome some of those therapeutic obstacles. Recently, atorvastatin (ATO) revealed antifungal activity. ATO is an antihyperlipidemic drug with pH-dependent solubility, which limits skin permeation. This study aims to improve ATO antifungal activity by encapsulation in an emulsomes (EMLs) system, which seeks to ameliorate skin penetration. Therefore, multiple factors were investigated according to the One-Factor-at-a-Time (OFAT) design to achieve the optimum formula with targeted characteristics. Minimizing particle-size and polydispersity-index, besides elevating zeta-potential (ZP) and entrapment-efficiency were the desirable responses during assessing 11 factors. The selected ATO-EMLs formula (E21) recorded 250.5 nm in particle size, polydispersity index of 0.4, ZP of -25.93 mV, and 83.12% of drug entrapped. Morphological study of E21 revealed spherical core-shell vesicles in nanosize. DSC, XRD, and FTIR were conducted to discover the physicochemical properties and confirm emulsomes formation. Optimized ATO-EMLs slowed drug release rate as only 75% of ATO was released after 72 h. Stability study recommended storage between 2 and 8 °C. The in vivo permeation study remarked a homogeneous penetration of EMLs in different skin layers. The in vivo skin irritation test revealed limited histopathological changes. The in vitro and in vivo microbiological studies demonstrated a good antifungal activity of ATO-EMLs. ATO-EMLs system improved antifungal activity as the MIC values reduced from 650 µg/mL for free ATO to 550 µg/mL for ATO-EMLs. These findings may shed light on ATO as an antifungal drug and nanosystems as a tool to support drug repurposing.

Atorvastatin-loaded emulsomes foam as a topical antifungal formulation.

Dermal fungal infection faces many challenges, especially for immunocompromised patients. Recently, the repositioning of atorvastatin (ATO) as a promising anti-mycoses therapy is used to overcome some issues of conventional therapeutic agents such as microbial resistance. The goal of this study was to develop a suitable formula for dermal fungal infection. Wherefore, ATO was entrapped into emulsomes and then incorporated in a foam system for topical convenient application. The D-optimal design was used for the optimization of ATO-emulsome and foam to achieve suitable responses. Regarding emulsomes, cholesterol weight and sonication time were independent variables that impact emulsome size, polydispersity index, surface charge, and entrapment efficiency. The optimum formula showed a size of 359.4 ± 8.97 nm, PDI of 0.4752 ± 0.012, a zeta potential of -21.27 ± 0.53 mV, and a drug entrapment of 95 ± 2.38%. Transmission electron microscope and Fourier-transform infrared spectroscopy (FT-IR) proved the assembly of ATO-emulsome. Foam composition was optimized to achieve good expansion, stability, and viscosity using a surfactant triple mixture and hydroxypropyl methylcellulose. The selected ATO-emulsome foam which consisted of 1% HPMC, 1.249% SDS, and 4% pluronic showed prolonged drug release. Efficient permeation through skin layers was asserted by using a confocal laser scanning microscope. Moreover, the homogenous distribution of the foam bubbles upholds stability and conserves the system from rapid collapse. The antifungal activity was confirmed by an in-vitro and in-vivo microbiology study beside in-vivo biocompatibility. In conclusion, ATO-emulsome and incorporation in foam have demonstrated good antifungal activity which presented a unique aspect for potential clinical applications.

Silica-Coated Magnetic Nanoparticles for Vancomycin Conjugation.

Drug resistance is a global health challenge with thousands of deaths annually caused by bacterial multidrug resistance (MDR). Efforts to develop new antibacterial molecules do not meet the mounting needs imposed by the evolution of MDR. An alternative approach to overcome this challenge is developing targeted formulations that can enhance the therapeutic efficiency and limit side effects. In this aspect, vancomycin is a potent antibacterial agent that has inherent bacterial targeting properties by binding to the D-Ala-D-Ala moiety of the bacterial peptidoglycan. However, the use of vancomycin is associated with serious side effects that limit its clinical use. Herein, we report the development of vancomycin-conjugated magnetic nanoparticles using a simple conjugation method for targeted antibacterial activity. The nanoparticles were synthesized using a multistep process that starts by coating the nanoparticles with a silica layer, followed by binding an amide linker and then binding the vancomycin glycopeptide. The developed vancomycin-conjugated magnetic nanoparticles were observed to exhibit a spherical morphology and a particle size of 16.3 ± 2.6 nm, with a silica coating thickness of 5 nm and a total coating thickness of 8 nm. The vancomycin conjugation efficiency on the nanoparticles was measured spectrophotometrically to be 25.1%. Additionally, the developed formulation retained the magnetic activity of the nanoparticles, where it showed a saturation magnetization value of 51 emu/g, compared to 60 emu/g for bare magnetic nanoparticles. The in vitro cell biocompatibility demonstrated improved safety where vancomycin-conjugated nanoparticles showed IC50 of 183.43 µg/mL, compared to a much lower value of 54.11 µg/mL for free vancomycin. While the antibacterial studies showed a comparable activity of the developed formulation, the minimum inhibitory concentration was 25 µg/mL, compared to 20 µg/mL for free vancomycin. Accordingly, the reported formulation can be used as a platform for the targeted and efficient delivery of other drugs.

Respirable spray dried vancomycin coated magnetic nanoparticles for localized lung delivery.

Bacterial pneumonia is a common pulmonary infection responsible for premature death. Biomaterials based-carriers loaded with antibiotics enhance drug potency through localizing the therapy, minimizing the associated adverse effects, and improving patient compliance. Herein, this study reports the preparation of an inhalable dry powder formulation composed of a nano-in-microparticles. Vancomycin was adsorbed on the core of magnetic nanoparticles followed by spray drying into lactose/dextran to optimize the aerodynamic performance and allow the local delivery of the drug into the bacterial pneumonia infection site. Lactose and Dextran are polysaccharides commonly used for pulmonary delivery due to their optimum aerodynamic performance and biocompatibility. The preparation of the nano-in-micro particles with optimum properties was confirmed using FTIR, TEM, SEM, Laser-diffraction, ICP-AES and TGA. The TEM micrographs confirmed the formation of spherical magnetic nanoparticles with a diameter 14.7 ± 5.9 nm and a coating thickness 3 - 16 nm, while laser diffraction showed that outer microparticles exhibited a mean diameter < 5 µm. The formulations demonstrated a promising activity against S. aureus and MRSA and better biocompatibility using MTT assay. In vivo safety and pharmacokinetic studies confirmed the localization of VAN in lung tissue and minimized adverse effects compared to free VAN. Therefore, the developed nano-in-microparticles confers a good potential for eradication of lung infections.

Nanoparticles Loaded Thermoresponsive In Situ Gel for Ocular Antibiotic Delivery against Bacterial Keratitis.

Antibiotics delivered through conventional dosage against ophthalmic infections show lower therapeutic efficacy due to their low residence time. Therefore, there is a great need to design and develop novel dosage forms that would increase the ocular residence time of antibiotics at the site of infection. This study describes the development of nanoparticles laden in situ gelling solution, intended to sustain antibiotic release for improved therapeutic efficiency. Oxytetracycline-loaded gelatin-polyacrylic acid nanoparticles were prepared and incorporated in poloxamer-N407 solution. The rheological properties of the system were studied concerning time and temperature. Moreover, in vivo biocompatibility of the system was ascertained using the Draize test and histological studies. Finally, the optimized formulation was evaluated for in vitro antibacterial activity against one of the most common keratitis causing bacteria, Pseudomonas aeruginosa. Additionally, the in vivo efficacy was evaluated on the rabbit's eye conjunctivitis model. The formulation showed a sustained effect against keratitis; furthermore, the antibacterial activity was comparable with the commercial product.