Development and Characterization of PEGylated Fatty Acid-Block-Poly(ε-caprolactone) Novel Block Copolymers and Their Self-Assembled Nanostructures for Ocular Delivery of Cyclosporine A

Low aqueous solubility and membrane permeability of some drugs are considered major limitations for their use in clinical practice. Polymeric micelles are one of the potential nano-drug delivery systems that were found to ameliorate the low aqueous solubility of hydrophobic drugs. The main objective of this study was to develop and characterize a novel copolymer based on poly (ethylene glycol) stearate (Myrj™)-block-poly(ε-caprolactone) (Myrj-b-PCL) and evaluate its potential as a nanosystem for ocular delivery of cyclosporine A (CyA). Myrj-b-PCL copolymer with various PCL/Myrj ratios were synthesized via ring-opening bulk polymerization of ε-caprolactone using Myrj (Myrj S40 or Myrj S100), as initiators and stannous octoate as a catalyst. The synthesized copolymers were characterized using 1H NMR, GPC, FTIR, XRD, and DSC. The co-solvent evaporation method was used to prepare CyA-loaded Myrj-b-PCL micelles. The prepared micelles were characterized for their size, polydispersity, and CMC using the dynamic light scattering (DLS) technique. The results from the spectroscopic and thermal analyses confirmed the successful synthesis of the copolymers. Transmission electron microscopy (TEM) images of the prepared micelles showed spherical shapes with diameters in the nano range (<200 nm). Ex vivo corneal permeation study showed sustained release of CyA from the developed Myrj S100-b-PCL micelles. In vivo ocular irritation study (Draize test) showed that CyA-loaded Myrj S100-b-PCL88 was well tolerated in the rabbit eye. Our results point to a great potential of Myrj S100-b-PCL as an ocular drug delivery system

Chitosan-Coated Flexible Liposomes Magnify the Anticancer Activity and Bioavailability of Docetaxel: Impact on Composition

Flexible liposomes (FLs) were developed as promising nano-carriers for anticancer drugs. Coating them with chitosan (CS) could improve their drug delivery properties. The aim of this study was to investigate the physicochemical characteristics, pharmacokinetics behavior, and cytotoxic efficacy of docetaxel (DTX)-loaded CS-coated FLs (C-FLs). DTX-loaded FLs and C-FLs were produced via thin-film evaporation and electrostatic deposition methods, respectively. To explore their physicochemical characterization, the particle size, zeta potential, encapsulation efficiency (EE%), morphology, and DTX release profiles were determined. In addition, pharmacokinetic studies were performed, and cytotoxic effect was assessed using colon cancer cells (HT29). Various FLs, dependent on the type of surfactant, were formed with particle sizes in the nano-range, 137.6 ± 6.3 to 238.2 ± 14.2 nm, and an EE% of 59–94%. Moreover, the zeta potential shifted from a negative to a positive value for C-FL with increased particle size and EE%, and the in vitro sustained-release profiles of C-FL compared to those of FL were evident. The optimized C-FL containing sodium deoxycholate (NDC) and dicetyl phosphate (DP) elicited enhanced pharmacokinetic parameters and cytotoxic efficiency compared to those of the uncoated ones and Onkotaxel®. In conclusion, this approach offers a promising solution for DTX delivery

Novel Metoprolol-Loaded Chitosan-Coated Deformable Liposomes in Thermosensitive In Situ Gels for the Management of Glaucoma: A Repurposing Approach

Glaucoma is a long-term eye disease associated with high intraocular pressure (IOP), which seriously damages the eyes, causing blindness. For successful therapy, potent drugs and delivery systems are required. Metoprolol (MT) is believed to help reduce elevated IOP. The paradigm of ocular therapeutics may be changed by the integration of chitosan-coated liposomes (CLPs) with thermosensitive in situ gel (ISG). Therefore, MT-CLPs were developed and characterized and compared to uncoated ones (MT-LPs). Furthermore, MT-LP- and MT-CLP-loaded ISGs were prepared and characterized in in vitro, ex vivo, and in vivo studies. MT-LPs and MT-CLPs displayed spherical shapes with nanosize range, reasonable EE%, and significant bioadhesion. The zeta potential changed from negative to positive after CS coating. The extended in vitro drug release of MT-CLPs showed significant mucin mucoadhesion. The formed ISGs were homogeneous with a pH range of 7.34 to 7.08 and a rapid sol–gel transition at physiological temperature. MT-ISG1 (MT-LP) and MT-ISG2 (MT-CLPs-0.5) could increase ocular permeability by 2-fold and 4.4-fold compared to MT-ISG (pure MT). MT-ISG2 demonstrated significantly reduced IOP in rabbits without causing any irritation. In conclusion, MT-ISG2 markedly enhanced corneal permeability and reduced IOP. They would be promising carriers for MT for glaucoma management

Chitosan-Coated Solid Lipid Nanoparticles as an Efficient Avenue for Boosted Biological Activities of <i>Aloe perryi</i>: Antioxidant, Antibacterial, and Anticancer Potential

Aloe perryi (ALP) is an herb that has several biological activities such as antioxidant, antibacterial, and antitumor effects and is frequently used to treat a wide range of illnesses. The activity of many compounds is augmented by loading them in nanocarriers. In this study, ALP-loaded nanosystems were developed to improve their biological activity. Among different nanocarriers, solid lipid nanoparticles (ALP-SLNs), chitosan nanoparticles (ALP-CSNPs), and CS-coated SLNs (C-ALP-SLNs) were explored. The particle size, polydispersity index (PDI), zeta potential, encapsulation efficiency, and release profile were evaluated. Scanning electron microscopy was used to see the nanoparticles’ morphology. Moreover, the possible biological properties of ALP were assessed and evaluated. ALP extract contained 187 mg GAE/g extract and 33 mg QE/g extract in terms of total phenolic and flavonoid content, respectively. The ALP-SLNs-F1 and ALP-SLNs-F2 showed particle sizes of 168.7 ± 3.1 and 138.4 ± 9.5 nm and the zeta potential values of −12.4 ± 0.6, and −15.8 ± 2.4 mV, respectively. However, C-ALP-SLNs-F1 and C-ALP-SLNs-F2 had particle sizes of 185.3 ± 5.5 and 173.6 ± 11.3 nm with zeta potential values of 11.3 ± 1.4 and 13.6 ± 1.1 mV, respectively. The particle size and zeta potential of ALP-CSNPs were 214.8 ± 6.6 nm and 27.8 ± 3.4 mV, respectively. All nanoparticles exhibited PDI P. aeruginosa, S. aureus, and E. coli, respectively. In addition, C-ALP-SLNs-F2 showed potential anticancer activity against A549, LoVo, and MCF-7 cell lines with IC50 values of 11.42 ± 1.16, 16.97 ± 1.93, and 8.25 ± 0.44, respectively. The results indicate that C-ALP-SLNs-F2 may be promising nanocarriers for enhancing ALP-based medicines

Optimization of cationic nanoparticles stabilized by poloxamer 188: A potential approach for improving the biological activity of Aloe perryi

Aloe perryi (AP) has gained considerable interest as a medicinal herb in various biological applications due to its rich phytochemical composition. However, the therapeutic benefits of AP could be potentiated by utilizing nanotechnology. Moreover, cationic solid lipid nanoparticles (CSLNs) possess remarkable characteristics that can greatly enrich a variety of biological uses. An optimization approach was used to achieve high-quality CSLNs to maximize the therapeutic efficacy of AP. Therefore, a factorial design was used to investigate the influence of various variables on the attributes of CSLNs quality. In this study, the factors under investigation were compritol 888 ATO (C-888, X1), poloxamer 188 (PL188, X2), and chitosan (CS, X3), which served as independent variables. The parameters measured as dependent variables included particle size (Y1), zeta potential (Y2), and encapsulation efficiency EE (Y3). The relationship among these variables was determined by Analysis of Variance (ANOVA) and response surface plots. The results revealed that PL188 played a significant role in reducing the particle size of CSLNS (ranging from 207 to 261 nm with 1 % PL188 to 167–229 nm with 3 % PL188). Conversely, an increase in the concentration of CS led to a rise in the particle size. The magnitude of positive zeta potential values was dependent on the increased concentration of CS. Moreover, the higher amounts of C-888 and PL188 improved the EE% of the CSLNs from 42 % to 86 %. Furthermore, a concentration-dependent antioxidant effect of the optimized AP-CSLNs was observed. The antioxidant activity of the optimized AP-CSLNs at 100 μg/mL was 75 % compared to 62 % and 60 % for AP-SLNs and AP solution, respectively. A similar pattern of improvement was also observed with antimicrobial, and anticancer activities of the optimized AP-CSLNs. These findings demonstrated the potential of AP-CSLNs as a carrier system, enhancing the biological activities of AP, opening new possibilities in herbal medicines

Co-Delivery of <i>Dragon’s Blood</i> and <i>Alkanna tinctoria</i> Extracts Using Electrospun Nanofibers: In Vitro and In Vivo Wound Healing Evaluation in Diabetic Rat Model

The increasing prevalence of diabetic wounds presents a significant challenge due to the difficulty of natural healing and various obstacles. Dragon’s blood (DB) and Alkanna tinctoria (AT) are well recognized for their potent healing abilities, which include potent antibacterial and anti-inflammatory activities. In this study, electrospun nanofibers (NFs) based on polyvinyl pyrrolidone (PVP) were co-loaded with both DB and AT, aiming to magnify their efficacy as wound-dressing applications for diabetic wound healing. The evaluation of these NFs as wound dressings was conducted using a streptozotocin-induced diabetic rat model. Electrospun NFs were prepared using the electrospinning of the PVP polymer, resulting in nanofibers with consistent, smooth surfaces. The loading capacity (LC) of AT and DB into NFs was 64.1 and 70.4 µg/mg, respectively, while in the co-loaded NFs, LC was 49.6 for AT and 57.2 µg/mg for DB. In addition, X-ray diffraction (XRD) revealed that DB and AT were amorphously dispersed within the NFs. The loaded NFs showed a dissolution time of 30 s in PBS (pH 7.4), which facilitated the release of AT and DB (25–38% after 10 min), followed by a complete release achieved after 180 min. The antibacterial evaluation demonstrated that the DB-AT mixture had potent activity against Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). Along with that, the DB-AT NFs showed effective growth inhibition for both P. aeruginosa and S. aureus compared to the control NFs. Moreover, wound healing was evaluated in vivo in diabetic Wistar rats over 14 days. The results revealed that the DB-AT NFs improved wound healing within 14 days significantly compared to the other groups. These results highlight the potential application of the developed DB-AT NFs in wound healing management, particularly in diabetic wounds