Non-destructive methods of characterization of risperidone solid lipid nanoparticles

Luliconazole-niacinamide lipid nanocarrier laden gel for enhanced treatment of vaginal candidiasis: in vitro, ex vivo, in silico and preclinical insights

A lipid-based nanocarrier system is a novel technique for the delivery of poorly soluble drugs through topical delivery. This study developed a dual-drug (luliconazole: LZ, and niacinamide: NM) loaded lipid nanocarrier (LN)-laden gel for the treatment of vaginal candidiasis. The LNs were prepared using cholesterol and soya-α-lecithin through a thin-film hydration technique. The average vesicle size, polydispersity index, and zeta potential of the optimized LZNMLNs were 126.40 ± 1.30 nm, 0.276, and -34.6 ± 0.8 mV, respectively, and the formulation showed the sustained release of both drugs over an extended period. Selected LZNMLNs were incorporated into a bio-adhesive gel. The optimized LZNMLNs-gel showed excellent viscosity, spreadability, and bio-adhesiveness. The optimized LZNMLNs-gel exhibited significantly higher permeation of LZ (1.46-fold) and NM (1.55-fold) than LZNM gel. The optimized LZNMLNs-gel showed significantly higher in vitro antifungal activity (ZOI = 34 ± 2 mm) than commercial Candid V gel (18 ± 1 mm). The optimized LZNMLNs-gel did not show any cytotoxicity against vaginal epithelial cells. The bioavailability of LZNMLNs-gel was significantly (P < 0.05) increased (1.94-fold for LZ and 1.33-fold for NM) compared to Candid V, with a decrease in total clearance indicating sustained release of the drug, which may lead to the maintenance of therapeutic concentration for an extended period. In vivo antifungal activity showed that the optimized LZNMLNs-gel completely treated the infection on the 7th day of treatment in an induced rabbit model, compared to the commercial gel (Candid V gel, 10 days). Based the findings, it can be concluded that LN-laden gel is an alternative carrier for improvement of the topical delivery of drugs for the treatment of vaginal candidiasis.

A quality-by-design approach to develop abemaciclib solid lipid nanoparticles for targeting breast cancer cell lines

AIM

Abemaciclib (ABE) is an anticancer drug that suffers from low bioavailability and multidrug resistance. This study aims to develop ABE-loaded solid lipid nanoparticles (ABE-SLNs), which will enhance drug solubility and lead to increased cellular uptake and enhanced cytotoxicity when delivering tumor cells.

METHODS

Melt emulsification followed by ultrasonication was used as a method of preparation and Quality-by-Design (QbD) was utilized to optimize ABE-SLNs.

RESULTS

The optimized ABE-SLNs consist of Precirol-ATO5 as a lipid and Brij-58 as a surfactant. The particle size, PDI value, and zeta potential of the optimized formulation were 170.4 ± 0.49 nm, 0.25 ± 0.014, and -26.4 ± 0.1 mV, respectively. It also showed sustained release behavior and a high entrapment efficiency of 79.96%. ABE-SLNs exhibited enhanced anticancer activity in the MDA-MB-231 and T47D breast cancer cell lines compared to pure ABE. In Caco-2 human colonic cell lines, ABE-SLNs also showed increased cellular uptake.

CONCLUSION

The use of QbD to achieve high entrapment efficiency and sustained release in ABE-SLNs, coupled with enhanced cellular uptake and cytotoxicity, represents a novel approach that could set a new standard for nanoparticle-based drug delivery systems.

Nondestructive techniques for pharmaceutical drug product characterization

Pharmaceutical product development involves multiple steps; therefore product quality must be assessed to ensure robustness and acceptability. Raw components, production methods, and ambient conditions yield highly variable end products with low batch-to-batch consistency. Although end testing is performed to ensure product quality, intermediate quality checks are limited. Nondestructive techniques like terahertz, near-infrared, X-ray, and Raman spectroscopy are common tools for in-line quality checks and real-time data monitoring. Handheld devices based on these analytical techniques also help in identifying counterfeit drugs products. This review discusses modern regulatory perspectives on the use of nondestructive tools in pharmaceutical quality monitoring.

New Insight for Enhanced Topical Targeting of Caffeine for Effective Cellulite Treatment: In Vitro Characterization, Permeation Studies, and Histological Evaluation in Rats

Cellulite (CLT) is one of the commonly known lipodystrophy syndromes affecting post-adolescent women worldwide. It is topographically characterized by an orange-peel, dimpled skin appearance hence, it is an unacceptable cosmetic problem. CLT can be modulated by surgical procedures such as; liposuction and mesotherapy. But, these options are invasive, expensive and risky. For these reasons, topical CLT treatments are more preferred. Caffeine (CA), is a natural alkaloid that is well-known for its prominent anti-cellulite effects. However, its hydrophilicity hinders its cutaneous permeation. Therefore, in the present study CA was loaded into solid lipid nanoparticles (SLNs) by high shear homogenization/ultrasonication. CA-SLNs were prepared using Compritol® 888 ATO and stearic acid as solid lipids, and span 60 and brij™35, as lipid dispersion stabilizing agents. Formulation variables were adjusted to obtain entrapment efficiency (EE > 75%), particle size (PS < 350 nm), zeta potential (ZP < -25 mV) and polydispersity index (PDI < 0.5). CA-SLN-4 was selected and showed maximized EE (92.03 ± 0.16%), minimized PS (232.7 ± 1.90 nm), and optimum ZP (-25.15 ± 0.65 mV) and PDI values (0.24 ± 0.02). CA-SLN-4 showed superior CA release (99.44 ± 0.36%) compared to the rest CA-SLNs at 1 h. TEM analysis showed spherical, nanosized CA-SLN-4 vesicles. Con-LSM analysis showed successful CA-SLN-4 permeation transepidermally and via shunt diffusion. CA-SLN-4 incorporated into Noveon AA-1® hydrogel (CA-SLN-Ngel) showed accepted physical/rheological properties, and in vitro release profile. Histological studies showed that CA-SLN-Ngel significantly reduced mean subcutaneous fat tissue (SFT) thickness with 4.66 fold (p = 0.035) and 4.16 fold (p = 0.0001) compared to CA-gel, at 7th and 21st days, respectively. Also, significant mean SFT thickness reduction was observed compared to untreated group with 4.83 fold (p = 0.0005) and 3.83 fold (p = 0.0043), at 7th and 21st days, respectively. This study opened new avenue for CA skin delivery via advocating the importance of skin appendages. Hence, CA-SLN-Ngel could be a promising nanocosmeceutical gel for effective CLT treatment.

Fresh Carrier for an Old Topical Local Anesthetic: Benzocaine in Nanostructured Lipid Carriers

Nanostructured lipid carriers (NLC) have emerged as innovative drug delivery systems, offering distinct advantages over other lipid-based carriers, such as liposomes and solid lipid nanoparticles. Benzocaine (BZC), the oldest topical local anesthetic in use, undergoes metabolism by pseudocholinesterase, leading to the formation of p-aminobenzoic acid, a causative agent for allergic reactions associated with prolonged BZC usage. In order to mitigate adverse effects and enhance bioavailability, BZC was encapsulated within NLC. Utilizing a 23 factorial design, formulations comprising cetyl palmitate (solid lipid), propylene glycol monocaprylate (liquid lipid), and Pluronic F68 as surfactants were systematically prepared, with variations in the solid/liquid lipid mass ratios (60:40-80:20%), total lipid contents (15-25%), and BZC concentrations (1-3%). The optimized formulation underwent characterization by dynamic light scattering, differential scanning calorimetry, Raman imaging, X-ray diffraction, small-angle neutron scattering, nanotracking analysis, and transmission electron microscopy (TEM)/cryo-TEM, providing insights into the nanoparticle structure and the incorporation of BZC into its lipid matrix. NLCBZC exhibited a noteworthy encapsulation efficiency (%EE = 96%) and a 1 year stability when stored at 25 °C. In vitro kinetic studies and in vivo antinociceptive tests conducted in mice revealed that NLCBZC effectively sustained drug release for over 20 h and prolonged the anesthetic effect of BZC for up to 18 h. We therefore propose the use of NLCBZC to diminish the effective anesthetic concentration of benzocaine (from 20 to 3% or less), thus minimizing allergic reactions that follow the topical administration of this anesthetic and, potentially, paving the way for new routes of BZC administration in pain management.

Virgin Coconut Oil-based Nanostructured Lipid Carrier Improves the Hypolipidemic Effect of Rosuvastatin

Background

Monitoring noncommunicable diseases is regarded as a critical concern that has to be managed in order to avoid a wide variety of complications such as increasing blood lipid levels known as dyslipidemia. Statin drugs, mostly, Rosuvastatin (RSV) was investigated for its effectiveness in treating dyslipidemia. However, reaching the most efficient treatment is essential and improving the effect of RSV is crucial. Therefore, a combination therapy was a good approach for achieving significant benefit. Although RSV is hydrophobic, which would affect its absorption and bioavailability following oral administration, overcoming this obstacle was important.

Purpose

To that end, the purpose of the present investigation was to incorporate RSV into certain lipid-based nanocarriers, namely, nanostructured lipid carrier (NLC) prepared with virgin coconut oil (CCO).

Methods

The optimized RSV-NLC formula was selected, characterized and examined for its in vitro, kinetic, and stability profiles. Eventually, the formula was investigated for its in vivo hypolipidemic action.

Results

The optimized NLC formulation showed a suitable particle size (279.3±5.03 nm) with PDI 0.237 and displayed good entrapment efficiency (75.6±1.9%). Regarding in vitro release, it was efficiently prolonged for 24 h providing 93.7±1.47%. The optimized formula was established to be stable after 3 months storage at two different conditions; 4°C and 25°C. Importantly, including CCO in the development of RSV-NLC could impressively enhance lowering total cholesterol level in obese rat models, which endorse the potential synergistic action between RSV and CCO.

Conclusion

The study could elucidate the impact of developing NLC using CCO for improving RSV anti-hyperlipidemic activity.

Effect of Cremophor RH40, Hydroxypropyl Methylcellulose, and Mixing Speed on Physicochemical Properties of Films Containing Nanostructured Lipid Carriers Loaded with Furosemide Using the Box-Behnken Design

This study aimed to examine the characteristics of H-K4M hydroxypropyl methylcellulose (HPMC) films containing nanostructured lipid carriers (NLCs) loaded with furosemide. A hot homogenization technique and an ultrasonic probe were used to prepare and reduce the size of the NLCs. Films were made using the casting technique. This study used a Box-Behnken design to evaluate the influence of three key independent variables, specifically H-K4M concentration (X1), surfactant Cremophor RH40 concentration (X2), and mixing speed (X3), on the physicochemical properties of furosemide-loaded NLCs and films. The furosemide-loaded NLCs had a particle size ranging from 54.67 to 99.13 nm, and a polydispersity index (PDI) ranging from 0.246 to 0.670. All formulations exhibited a negative zeta potential, ranging from -7.05 to -5.61 mV. The prepared films had thicknesses and weights ranging from 0.1240 to 0.2034 mm and 0.0283 to 0.0450 g, respectively. The drug content was over 85%. Film surface wettability was assessed based on the contact angle, ranging from 32.27 to 68.94°. Film tensile strength varied from 1.38 to 7.77 MPa, and their elongation at break varied from 124.19 to 170.72%. The ATR-FTIR analysis confirmed the complete incorporation of the drug in the film matrix. Therefore, the appropriate selection of values for key parameters in the synthesis of HPMC films containing drug-loaded NLCs is important in the effective development of films for medical applications.

Optimized lipopolymers with curcumin to enhance AZD5582 and GDC0152 activity and downregulate inhibitors of apoptosis proteins in glioblastoma multiforme

Inhibition to glioblastoma multiforme (GBM) propagation is a critical challenge in clinical practice because binding of inhibitors of apoptosis proteins (IAPs) to caspase prevents cancer cells from death. In this study, folic acid (FA), lactoferrin (Lf) and rabies virus glycoprotein (RVG) were grafted on lipopolymers (LPs) composed of poly(ε-caprolactone) and Compritol 888 ATO to encapsulate AZD5582 (AZD), GDC0152 (GDC) and curcumin (CURC). The standard deviations of initial particle diameter and particle diameter after storage for 30 days were involved in LP composition optimization. The functionalized LPs were used to permeate the blood-brain barrier (BBB) and constrain IAP quantity in GBM cells. Experimental results revealed that an increase in Span 20 (emulsifier) concentration enlarged the size of LPs, and enhanced the entrapment and releasing efficiency of AZD, DGC and CURC. 1H nuclear magnetic resonance spectra showed that the hydrogen bonds between the LPs and drugs supported the sustained release of AZD, DGC and CURC from the LPs. The LPs modified with the three targeting biomolecules facilitated the penetration of AZD, GDC and CURC across the BBB, and could recognize U87MG cells and human brain cancer stem cells. Immunofluorescence staining, flow cytometry and western blot demonstrated that CURC-incorporated LPs enhanced AZD and GDC activity in suppressing cellular IAP 1 (cIAP1) and X-linked IAP (XIAP) levels, and raising caspase-3 level in GBM. Surface FA, Lf and RVG also promoted the ability of the drug-loaded LPs to avoid carcinoma growth. The current FA-, Lf- and RVG-crosslinked LPs carrying AZD, DGC and CURC can be promising in hindering IAP expressions for GBM management.

Design of experiments approach for the development of a validated method to determine the exenatide content in poly(lactide-co-glycolide) microspheres

Due to the lack of pharmacopeia guidelines for injectable microspheres based on poly (D, L-lactide-co-glycolide) (PLGA), an internal method validation is a critical prerequisite for quality assurance. One of the essential issues of developing peptide-based drugs loaded PLGA microspheres is the precise determination of the amount of peptide drug entrapped in the microspheres. The aim of this study is the development and optimization of a method for measuring the drug content loading of PLGA microspheres using exenatide as a model peptide drug. Exenatide-loaded PLGA microspheres were prepared by a double emulsion solvent evaporation method. The extraction method to determine exenatide content in microspheres was optimized using Design of Experiments (DoE) approach. After the initial screening of six factors, using Fractional Factorial design (FFD), four of them, including type of organic solvent, buffer/organic solvent ratio (v/v), shaking time and pH, exhibited significant effects on the response, namely the exenatide loading, and a Box-Behnken design (BBD) was subsequently applied to obtain its optimum level. The optimum level for organic solvent volume, buffer/organic solvent ratio, shaking time, and pH were 4 ml, 1, 5.6 hrs, and pH 6, respectively. The exenatide content in microspheres under these conditions was 6.4 ± 0.0 (%w/w), whereas a value of 6.1% was predicted by the derived equation. This excellent agreement between the actual and the predicted value demonstrates that the fitted model can thus be used to determine the exenatide content.

Advanced multifunctional nano-lipid carrier loaded gel for targeted delivery of 5-flurouracil and cannabidiol against non-melanoma skin cancer

Non-melanoma skin cancer is one of the most common malignancies reported around the globe. Current treatment therapies fail to meet the desired therapeutic efficacy due to high degree of drug resistance. Thus, there is prominent demand in advancing the current conventional therapy to achieve desired therapeutic efficacy. To break the bottleneck, nanoparticles have been used as next generation vehicles that facilitate the efficient interaction with the cancer cells. Here, we developed combined therapy of 5-fluorouracil (5-FU) and cannabidiol (CBD)-loaded nanostructured lipid carrier gel (FU-CBD-NLCs gel). The current investigation has been designed to evaluate the safety and efficacy of developed 5-Flurouracil and cannabidiol loaded combinatorial lipid-based nanocarrier (FU-CBD NLCs) gel for the effective treatment of skin cancer. Initially, confocal microscopy study results showed excellent uptake and deposition at epidermal and the dermal layer. Irritation studies performed by IR camera and HET cam shows FU-CBD NLCs was much more tolerated and less irritant compared to conventional treatment. Furthermore, gamma scintigraphy evaluation shows the skin retention behavior of the formulation. Later, in-ovo tumor remission studies were performed, and it was found that prepared FU-CBD NLCs was able to reduce tumor volume significantly compared to conventional formulation. Thus, obtained results disclosed that permeation and disposition of 5-FU and CBD into different layers of the skin FU-CBD NLCs gel could be more potential carrier than conventional gel. Furthermore, prepared formulation showed greater tumor remission, better survival rate, reduction in tumor number, area, and volume with improved biochemical profile. Thus, prepared gel could serve as a promising formulation approach for the skin cancer treatment.

Solid lipid Lyo-Nanosuspension: A promising stabilized oral delivery system for the antihyperglycemic extract of mistletoe Plicosepalus acacia

The antihyperglycemic effect of Plicosepalus acaciae (P. acaciae) extract was proven, but it still needs to be formulated into a suitable dosage form. We aimed at preparing an oral stabilized SLNs for P. acaciae with high payload, to be used as powder for reconstitution, filled into capsule or compressed into tablet. SLNs were prepared by emulsion solvent evaporation technique. Preliminary characterization was performed followed by full assessment of the optimized SLNs suspension and/or its lyophilized form: particle size, zeta potential, surface morphology, percentage entrapment efficiency (% EE), DSC, FTIR and in vitro release studies. The optimized SLNs lyophilized formula (F3_L) exhibited acceptable compressibility and flowability. The reconstituted F3L showed % sedimentation volume of 91.83 %, re-dispersibility of 95%, viscosity of 764.33 cp, uniform particle size of 30.28 nm as shown by TEM, polydispersity index (PDI) of 0.16, zeta potential of -36.4 mV, % EE of 89.64 % and drug content of 97.69 %. The physical mixture and F3_L FTIR spectrum indicated compatibility of components. In vitro release study showed a burst release in lyophilized formulations followed by slow-release, calculated as total phenolic content. Our previously reported work revealed that the total extracts of P. acaciae and SLNs formulations with the greatest lipid content F3_s, demonstrated a considerable blood glucose-lowering effect in diabetic rats. The obtained lyophilized SLNs is promising for preparation of a suitable stable dosage form for P. acaciae extract to be used in treatment of diabetes.

Enhancement of in-vitro anti-oral cancer activities of silymarin using dispersion of nanostructured lipid carrier in mucoadhesive in-situ gel

Silymarin (SME) shows multiple therapeutic actions against several cancers, however, low aqueous solubility and poor bioavailability issues restrict its clinical use. In this study, SME was loaded in nanostructured lipid carriers (NLCs) and further incorporated in mucoadhesive in-situ gel (SME-NLCs-Plx/CP-ISG) for localized treatment of oral cancer. Using a 3³ Box-Behnken design (BBD), an optimized SME-NLC formula was developed with the ratios of solid lipids, surfactant concentration, and sonication time as independent variables, while particle size (PS), polydispersity index (PDI), and % encapsulation efficiency (EE) as dependent variables, resulting in 315.5 ± 0.1 nm PS, 0.341 ± 0.01 PDI, and 71.05 ± 0.05 % EE. Structural studies confirmed the formation of SME-NLCs. SME-NLCs incorporated in-situ gel demonstrated a sustained release for SME, indicating enhanced retention on the buccal mucosal membrane. The in-situ gel containing SME-NLCs showed a marked decrease in IC₅₀ value (24.90 ± 0.45 µM) than SME-NLCs (28.40 ± 0.89 µM) and plain SME (36.60 ± 0.26 µM). The studies demonstrated that Reactive oxygen species (ROS) generation potential and SME-NLCs-Plx/CP-ISG induced apoptosis at Sub-G0 phase owing to higher penetration of SME-NLCs led to higher inhibition against human KB oral cancer cells. Therefore, SME-NLCs-Plx/CP-ISG can be the alternative to chemotherapy and surgery with site-specific delivery of SME to oral cancer patients.

Vitamin D3-Loaded Nanoemulsions as a Potential Drug Delivery System for Autistic Children: Formulation Development, Safety, and Pharmacokinetic Studies

The aim of the current study is the development of a vitamin D₃ (VD3)-loaded nanoemulsion (NE) formulation to improve VD3 oral bioavailability for management of vitamin D inadequacy in autistic children. Eight NE formulations were prepared by high-speed homogenization followed by ultrasonication. Four vegetable oils were employed along with two concentrations of Span 20 as the emulsifier. Glycerol, fructose, and mango flavor were included as viscosity modifier, sweetening, and flavoring agents, respectively. The prepared VD3-loaded NE formulations exhibited high drug content (> 98%), droplet size (DS) ranging from 61.15 to 129.8 nm with narrow size distribution, zeta potential values between - 9.83 and - 19.22 mV, and acceptable pH values (4.59-5.89). Storage stability showed that NE formulations underwent coalescence and phase separation during 6 months at room temperature, whereas at refrigerated conditions, formulations showed slight creaming. The optimum formulation (VD3-NE6) revealed a non-significant DS growth at refrigerated conditions and spherical morphology under transmission electron microscopy. VD3-NE6 did not produce any toxic effects to rats treated orally for 3 months, where normal blood picture and kidney and liver functions were observed compared to control rats. Also, serum calcium, oxidative stress, and apoptosis biomarkers remained within normal levels, indicating the safety of the optimum formulation. Furthermore, evaluation of VD3-NE6 oral bioavailability depicted a significant increase in AUC_0-72 and C_max with decreased T_max compared to plain VD3. The optimum formulation demonstrated improved stability, safety, and oral bioavailability indicating the potential for successful management of vitamin D deficiency in autistic children.

Tailoring Apixaban in Nanostructured Lipid Carrier Enhancing Its Oral Bioavailability and Anticoagulant Activity

Apixaban (Apx), an oral anticoagulant drug, is a direct factor Xa inhibitor for the prophylaxis against venous thromboembolism. Apx has limited oral bioavailability and poor water solubility. The goal of this study was to improve the formulation of an Apx-loaded nanostructured lipid carrier (NLC) to increase its bioavailability and effectiveness. As solid lipid, liquid lipid, hydrophilic, and lipophilic stabilizers, stearic acid, oleic acid, Tween 80, and lecithin were used, respectively. Utilizing Box-Behnken design, the effects of three factors on NLC particle size (Y1), zeta potential (Y2), and entrapment efficiency percent (Y3) were examined and optimized. The optimized formula was prepared, characterized, morphologically studied, and pharmacokinetically and pharmacodynamically assessed. The observed responses of the optimized Apx formula were 315.2 nm, -43.4 mV, and 89.84% for Y1, Y2, and Y3, respectively. Electron microscopy revealed the homogenous spherical shape of the NLC particles. The in vivo pharmacokinetic study conducted in male Wistar rats displayed an increase in AUC and Cmax by 8 and 2.67 folds, respectively, compared to oral Apx suspension. Moreover, the half-life was increased by 1.94 folds, and clearance was diminished by about 8 folds, which makes the NLC formula a promising sustained release system. Interestingly, the pharmacodynamic results displayed the superior effect of the optimized formula over the drug suspension with prolongation in the cuticle bleeding time. Moreover, both prothrombin time and activated partial thromboplastin time are significantly increased. So, incorporating Apx in an NLC formula significantly enhanced its oral bioavailability and pharmacodynamic activity.

Quercetin Loaded Cationic Solid Lipid Nanoparticles in a Mucoadhesive In Situ Gel-A Novel Intravesical Therapy Tackling Bladder Cancer

The study aim was to develop an intravesical delivery system of quercetin for bladder cancer management in order to improve drug efficacy, attain a controlled release profile and extend the residence time inside the bladder. Either uncoated or chitosan coated quercetin-loaded solid lipid nanoparticles (SLNs) were prepared and evaluated in terms of colloidal, morphological and thermal characteristics. Drug encapsulation efficiency and its release behaviour were assessed. Furthermore, cytotoxicity of SLNs on T-24 cells was evaluated. Ex vivo studies were carried out using bovine bladder mucosa. Spherical SLNs (≈250 nm) ensured good entrapment efficiencies (EE > 97%) and sustained drug release up to 142 h. Cytotoxicity profile revealed concentration-dependent toxicity recording an IC50 in the range of 1.6−8.9 μg/mL quercetin. SLNs were further dispersed in in situ hydrogels comprising poloxamer 407 (20%) with mucoadhesive polymers. In situ gels exhibited acceptable gelation temperatures (around 25 °C) and long erosion time (24−27 h). SLNs loaded gels displayed remarkably enhanced retention on bladder tissues relative to SLNs dispersions. Coated SLNs exhibited better penetration abilities compared to uncoated ones, while coated SLNs dispersed in gel (G10C-St-QCT-SLNs-2) showed the highest penetration up to 350 μm. Hence, G10C-St-QCT-SLNs-2 could be considered as a platform for intravesical quercetin delivery.

Augmented Oral Bioavailability and Prokinetic Activity of Levosulpiride Delivered in Nanostructured Lipid Carriers

The present study is aimed to develop and optimize levosulpiride-loaded nanostructured lipid carriers (LSP-NLCs) for improving oral bioavailability and prokinetic activity of LSP. LSP-NLCs were optimized with D-optimal mixture design using solid lipid, liquid lipid and surfactant concentrations as independent variables. The prepared LSP-NLCs were evaluated for physicochemical properties and solid-state characterization. The in vivo oral pharmacokinetics and prokinetic activity of LSP-NLCs were evaluated in rats. LSP-NLCs formulation was optimized at Precirol® ATO 5/Labrasol (80.55/19.45%, w/w) and Tween 80/Span 80 concentration of 5% (w/w) as a surfactant mixture. LSP-NLCs showed a spherical shape with a particle size of 152 nm, a polydispersity index of 0.230 and an entrapment efficiency of 88%. The DSC and PXRD analysis revealed conversion of crystalline LSP to amorphous state after loading into the lipid matrix. LSP-NLCs displayed a 3.42- and 4.38-flods increase in AUC and Cmax after oral administration compared to LSP dispersion. In addition, LSP-NLCs showed enhanced gastric emptying (61.4%), intestinal transit (63.0%), and fecal count (68.8) compared to LSP dispersion (39.7%, 38.0% and 51.0, respectively). Taken together, these results show improved oral bioavailability and prokinetic activity of LSP-NLCs and presents a promising strategy to improve therapeutic activity of LSP for efficient treatment of gastric diseases.

Hyaluronic acid-coated solid lipid nanoparticles enhance antirheumatic activity and reduce toxicity of methotrexate

Aim: Methotrexate (MTX) is used to treat rheumatoid arthritis (RA) but is associated with severe toxicity. To minimize these side effects of MTX, the study was undertaken to explore its delivery using solid lipid nanoparticles (SLNs). Materials & methods: MTX-loaded SLNs were synthesized and coated with hyaluronic acid (HA) for targeted drug delivery and evaluated for their safety and efficacy in a complete Freund's adjuvant (CFA) model. Results: HA-MTX-SLNs (230.0 ± 46.4 nm) with 78.75% entrapment were developed and showed sustained drug release with a significant reduction in toxicity and enhanced activity of the drug at the targeted site upon oral administration in CFA-induced rats. Conclusion: HA-MTX-SLNs can be considered as an efficient therapeutic agents for the treatment of RA.

Engineering biosafe cisplatin loaded nanostructured lipid carrier: optimisation, synthesis, pharmacokinetics and biodistribution

Low aqueous solubility, adverse effects of Cisplatin includes hepatotoxicity and nephrotoxicity necessitates development of nanoparticulate drug delivery. The study pertains to development of CisNLC (Cisplatin loaded Nanostructured Lipid Carrier) by ultrasonication. Physical characterisation includes particle size, zeta potential, TEM, SEM-EDX, DSC. Its ex vivo biocompatibility, pharmacokinetics and biodistribution along with acute toxicity induced oxidative stress in Balb/c mice were evaluated. The mean particle diameter of CisNLC was observed to be 141.5 ± 3.86 nm with zeta potential of -41.5 ± 1.62 mV. In vitro release studies at pH 7.4 and 5.8 showed burst release following a sustained release pattern post-72 h. CisNLC showed anticancer efficacy against PA-1. Negligible ex vivo haemolysis indicated bio-compatibility. Improved pharmacokinetics of CisNLC was observed. Acute toxicity and oxidative stress evaluation proved negligible toxicity by CisNLC. The formulated CisNLC had a good physical stability, biocompatible, indicated enhanced circulation and caused negligible toxicity on liver and kidney as compared to pure Cis.

Hypolipidemic Activity of Olive Oil-Based Nanostructured Lipid Carrier Containing Atorvastatin

Currently, hyperlipidemia is a growing health issue that is considered a risk factor for obesity. Controlling body weight and modifying life style in most of cases are not adequate and the condition requires medical treatment. Statin drugs (mainly Atorvastatin (ATO)), have been used broadly and for long time as medications for handling higher levels of lipid, especially bad cholesterol, which accordingly controls the prevalence of obesity. Still, the obstacle that stands in front of any formulation is the poor solubility of the drug. Low solubility of ATO came up with poor absorption as well as poor bioavailability. This paved the way for the present study, which aimed to exploit nanotechnology and develop certain nanolipid carriers that could accommodate hydrophobic drugs, such as ATO. Nanostructured lipid carrier (NLC) containing ATO was fabricated using olive oil. Olive oil is natural plant oil possessing confirmed hypolipidemic activity that would help in improving the efficacy of the formulation. Via applying the Quality by Design (QbD) approach, one NLC formula was selected to be optimized based on appropriate size and higher entrapment. Optimized ATO-NLC was scrutinized for zeta potential, in vitro study and kinetic profile. Moreover, stability testing and in vivo hypolipidemic behavior was conducted. The optimized NLC formulation seemed to show particle size (254.23 nm) with neutral zeta potential (−1.77 mV) and entrapment efficiency (69.56%). The formulation could be prolonged for 12 h and provided higher % of release (97.17%). Stability testing confirmed the role of modifying the surface of the formulation with PEG-DSPE in providing a highly stable formulation that could withstand three months storage in two altered conditions. Ultimately, optimized ATO-NLC could successfully lower total cholesterol level in rats induced with obesity and fed a high-fat diet. Remarkably, ATO-NLC prepared with olive oil, in addition to shielding its surface, would provide a stable formulation that holds up the synergistic action between olive oil and ATO.

Shea Butter Potentiates the Anti-Bacterial Activity of Fusidic Acid Incorporated into Solid Lipid Nanoparticle

Fusidic acid (FA) is an efficient anti-bacterial drug proven to be efficient against a wide range of bacteria. Nevertheless, the main restriction in its formulation is the limited solubility. To avoid such an obstacle, the drug is incorporated into the lipid core of the nanolipid formulation. Consequently, the present study was an attempt to formulate nanolipid preparation, mainly, solid lipid nanoparticle (SLN) integrating FA. FA-SLN was prepared using shea butter as a lipid phase owing to its reported anti-bacterial activity. Different FA-SLNs were fabricated using the central composite design (CCD) approach. The optimized formula was selected and integrated into a hydrogel base to be efficiently used topically. FA-SLN-hydrogel was evaluated for its character, morphology, in vitro release and stability. The formula was examined for irritation reaction and finally evaluated for its anti-bacterial performance. The optimized formula showed particle size 283.83 nm and entrapment 73.057%. The formulated FA-SLN-hydrogel displayed pH 6.2, viscosity 15,610 cP, spreadability 51.1 mm and in vitro release 64.6% following 180 min. FA-SLN-hydrogel showed good stability for three months at different conditions (room temperature and refrigerator). It exhibited no irritation reaction on the treated rats. Eventually, shea butter displayed a noteworthy effect against bacterial growth that improved the effect of FA. This would indicate prospective anti-bacterial activity of FA when combined with shea butter in SLN formulation as a promising nanocarrier.

Transferrin-Modified Mangiferin-Loaded SLNs: Preparation, Characterization, and Application in A549 Lung Cancer Cell

Introduction

Mangiferin is a plant antitumor compound with poor water solubility and low bioavailability. In this study, transferrin-modified mangiferin-loaded solid lipid nanoparticles (Tf-modified MGF-SLNs) were prepared to overcome the above defects.

Methods

Tf-modified MGF-SLNs were prepared by the emulsification-solvent evaporation method. The physicochemical properties of Tf-MGF-SLNs such as particle size, zeta potential and in vitro drug release were investigated. We also demonstrated the effect of Tf-MGF-SLNs in lung cancer.

Results

The mean hydrodynamic diameter of the Tf-MGF-SLNs was 121.8±2.9 nm with a polydispersity index of 0.134±0.03. According to TEM micrographs, Tf-MGF-SLNs are spherical and uniform, and the EE% was found to be 72.5±2.4%. In vitro release, we identified an initial burst effect release, followed by controlled release, in SLNs at both pHs and the Tf-MGF-SLNs drug accumulation release percentages reached over 68% at pH 4.0 and 72% at pH 7.4 in 6 hours, respectively. In vivo studies showed that depending on surface modification, Tf-MGF-SLNs, which suggested that cell internalization was changed and more drugs entered the cells successfully.

Discussion

Tf-MGF-SLNs were highly efficient in suppressing the tumor growth in xenograft tumor model. Sustained release of the drug delivery system and Tf-modified MGF-SLNs played a major role. Tf-MGF-SLNs would be a promising formulation for the treatment of lung cancer.

Aerosolizable Lipid-Nanovesicles Encapsulating Voriconazole Effectively Permeate Pulmonary Barriers and Target Lung Cells

The entire world has recently been witnessing an unprecedented upsurge in microbial lung infections. The major challenge encountered in treating the same is to ensure the optimum drug availability at the infected site. Aerosolization of antimicrobials, in this regard, has shown immense potential owing to their localized and targeted effect. Efforts, therefore, have been undertaken to systematically develop lung-phosphatidylcholine-based lipid nanovesicles of voriconazole for potential management of the superinfections like aspergillosis. LNVs, prepared by thin-film hydration method, exhibited a globule size of 145.4 ± 19.5 nm, polydispersity index of 0.154 ± 0.104 and entrapment efficiency of 71.4 ± 2.2% with improved in vitro antifungal activity. Aerodynamic studies revealed a microdroplet size of ≤5 μm, thereby unraveling its promise to target the physical barrier of lungs effectively. The surface-active potential of LNVs, demonstrated through Langmuir-Blodgett troughs, indicated their ability to overcome the biochemical pulmonary surfactant monolayer barrier, while the safety and uptake studies on airway-epithelial cells signified their immense potential to permeate the cellular barrier of lungs. The pharmacokinetic studies showed marked improvement in the retention profile of voriconazole in lungs following LNVs nebulization compared to pristine voriconazole. Overall, LNVs proved to be safe and effective delivery systems, delineating their distinct potential to efficiently target the respiratory fungal infections.

Evaluation of the hepatoprotective effect of curcumin-loaded solid lipid nanoparticles against paracetamol overdose toxicity: Role of inducible nitric oxide synthase

Curcumin (Cur) is a natural compound that exhibited therapeutic effects against various liver injuries however Cur showed poor water solubility and bioavailability. This study aimed to design Cur-loaded solid lipid nanoparticles (SLNs) and to evaluate the hepatoprotective and antioxidant effects in a model of acute hepatotoxicity induced by paracetamol (PCM) overdose compared to the raw Cur and N-acetylcysteine (NAC). SLNs were prepared by emulsion/solvent evaporation method and 3² factorial design was employed. Wistar rats were divided into Control, PCM, PCM + NAC, PCM + raw Cur, and PCM + Cur-SLNs groups and treated orally for 14 days before receiving a single PCM dose. The Cur-loaded SLNs showed high entrapment efficiency % ranging between 69.1 and 92.1%, particle size (PS) between 217 and 506 nm, and zeta potential values between -17.9 and -25.5 mV. The in vivo results revealed that the PCM group exhibited deterioration of liver functions, pathological lesions on the liver tissues, severe oxidative stress, and increases in both the serum and hepatic iNOS levels. Remarkably, the PCM + Cur-SLNs group showed significantly better liver functions and tissue integrity compared to the PCM group. Furthermore, higher reduced glutathione and catalase but lower malondialdehyde and iNOS levels were observed. In conclusion, Cur-loaded SLNs effectively prevented the liver damage induced by PCM overdose through alleviating the oxidative stress and inhibiting the serum and hepatic iNOS expression in an effect comparable to NAC and better than raw Cur.

Encapsulation of safflower oil in nanostructured lipid carriers for food application

Safflower oil (SO) is mainly rich in linoleic acid (ω-6), oleic acid (ω-9), and other bioactives with potential antioxidant, antidiabetic, thermogenic, anti-inflammatory, cardioprotective and anticancer activities. The reduced aqueous solubility and high susceptibility to oxidative degradation are undesirable for food applications and can be overcome by incorporation in lipid nanoparticles. Thus, the main goal was to develop and characterize SO-loaded nanostructured lipid carriers (NLC-SO) and to evaluate their potential for protection of the antioxidant activity of the bioactive. NLC-SO showed average size of 222 ± 2.0 nm, zeta potential of  43 ± 3.5 mV and the encapsulation efficiency was 49.0 ± 2.8%, combined with high thermal compatibility (up to 228 °C) and physical stability for up to 60 days in aqueous dispersion. Besides, the NLC-SO showed threefold reduction in the DPPH radical scavenge activity after encapsulation, indicating protection of the antioxidant components of the SO and preservation of the bioactives.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13197-021-05078-5.

Multivesicular liposomal depot system for sustained delivery of risperidone: development, characterization, and toxicity assessment

OBJECTIVE

Considering the limitations of conventional risperidone (RSP) therapies, the present research characterizes the usefulness of multivesicular liposomes (MVLs) as an efficient controlled-release carrier for this widely used antipsychotic drug, to be employed for the treatment of schizophrenia.

METHODS

A 2³ full factorial design based on three independent variables was implemented to plan the experiments: the molar ratios of lipid to the drug, triolein to phospholipid, and cholesterol to phospholipid. The impacts of these parameters on the risperidone encapsulation efficiency and its release pattern within the first 24 and 48 h were investigated as dependent variables. Then, the optimized liposomal system was further in-depth analyzed in terms of size, morphological and structural features, release profile over 15 days, biocompatibility, and stability.

RESULTS

Optimized formulation parameters gave rise to MVLs possessing a spherical morphology with a median diameter of about 8 μm, a relatively narrow size distribution (span value of 1.49), and an encapsulation efficiency of 57.6%. These carriers not only exhibited a sustained-release behavior in vitro, lasting until the end of the 15 days but also underwent a negligible change in their size and RSP incorporation over two months at refrigerator condition. Furthermore, in vitro cytotoxicity and hemolysis assessments revealed that the optimized MVL formulation is biocompatible.

CONCLUSION

This study revealed the potential of MVLs as a promising system for the delivery of RSP and could open a new vista for the successful management of schizophrenia.

Lipid nanoparticles loaded with butamben and designed to improve anesthesia at inflamed tissues

The most frequently used local anesthetics (LA) for local infiltration have an ionizable amine in the range of pH 7.6-8.9. Effective anesthesia of inflamed tissues is a great challenge, especially because the induced local acidosis decreases the fraction of the neutral (more potent) LA species in situ. To solve this limitation, the butyl-substituted benzocaine analogue butamben (BTB) - that has no ionizable amine group close to the physiological pH - could be useful if it was not for its low solubility. To overcome the solubility problem, an optimized formulation for BTB using nanostructured lipid carriers (NLC) was developed by a factorial design and characterized using DLS, XRD, DSC and cryo-EM. The release kinetics and cytotoxicity of the new formulation were measured in vitro, while the in vivo tests assessed its effectiveness on healthy and inflamed tissues, in rats. The optimized NLCBTB formulation showed desirable physicochemical properties (size = 235.6 ± 3.9 nm, polydispersity = 0.182 ± 0.006 and zeta potential = -23.6 ± 0.5 mV), high (99.5%) encapsulation efficiency and stability during 360 days of storage at room temperature. NLCBTB prolonged the release of butamben and decreased its in vitro cytotoxicity without inducing any in vivo toxic alteration. In the inflammatory hyperalgesia model, the NLCBTB formulation showed potential for the management of inflammatory pain, displaying greater analgesic effectiveness (40%) and a prolonged effect.

Preparation, Statistical Optimization and In-vitro Characterization of a Dry Powder Inhaler (DPI) Containing Solid Lipid Nanoparticles Encapsulating Amphotericin B: Ion Paired Complexes with Distearoyl Phosphatidylglycerol

The aim of this study was to prepare dry powder inhalers (DPIs) containing amphotericin B-loaded solid lipid nanoparticles (AMB-SLNs) as an alternative approach for prevention of pulmonary aspergillosis. For solubilizing AMB in small amounts of organic solvents ion paired complexes were firstly formed by establishing electrostatic interaction between AMB and distearoyl phosphatidylglycerol (DSPG). The SLN formulations containing AMB-DSPG complexes were prepared using glycerol monostearate (GMS) as the lipid matrix and soybean lecithin and tween 80 as the surfactants by solvent emulsification-evaporation technique. The nanoparticles were optimized through a fractional factorial design. DPIs were prepared by lyophilization technique using lactose as the inhalational carrier and then after, the formulations were evaluated in terms of aerodynamic particle size distribution using an Andersen cascade impactor. The morphology of the particles was examined using scanning electron microscopy (SEM) and in-vitro drug release profiles were evaluated. Following the statistical results, the particle size, Poly dispersity index (PdI), zeta potential, entrapment efficiency (EE%), and drug loading (DL%) of the optimized SLNs were 187.04 ± 11.97 nm, 0.188 ± 0.028, -30.16 ± 1.6 mV, 89.3 ± 3.47 % and 2.76 ± 0.32 %, respectively. Formulation containing 10% w/v of lactose with the calculated fine particle fraction value as 72.57 ± 4.33% exhibited the appropriate aerodynamic characteristics for pulmonary drug delivery. SEM images revealed de-agglomerated particles. In-vitro release studies showed sustained release of AMB from the carriers and the release kinetics were best fitted to the first order kinetic model.

Intranasal delivery of Naloxone-loaded solid lipid nanoparticles as a promising simple and non-invasive approach for the management of opioid overdose

Naloxone is an opioid receptor antagonist that can eradicate all pre-indications of the toxicity and inverse the opioid overdose. However, oral administration of naloxone offers limitations such as its extensive first-pass metabolism that results in poor therapeutic effects. In order to resolve this issue, we developed intranasal solid-lipid nanoparticles in which naloxone was incorporated for the higher brain disposition of naloxone with superior therapeutic effects for the reversal of toxicity of opioid overdose. The preparation of naloxone loaded solid-lipid nanoparticles was done by employing the solvent evaporation method. Later, the designed formulation was optimized by Quality by Design approach, specifically, Box-Behnken method. The composition of optimized formulation was Glyceryl monostearate as a solid lipid (40 mg), Pluronic127 (0.5%) and Tween 80 (0.1%) as a surfactant and co-surfactant, respectively. Furthermore, the characterization of optimized formulation was achieved in terms of particle size, PDI, zeta potential, entrapment efficiency, and drug loading which were 190.2 nm, 0.082, -16 mV, 95 ± 0.532% and 19.08 ± 0.106%, respectively. Afterwards, in vitro, ex vivo and in vivo experiments were performed in which higher drug release and superior drug uptake by nasal membrane were observed for naloxone-loaded solid-lipid nanoparticles, later it was confirmed by confocal microscopy of ex vivo nasal membrane tissue. The findings of gamma scintigraphy investigation exhibited better deposition of naloxone-loaded solid-lipid nanoparticles as compared to naloxone solution. Also, the better deposition of naloxone by gamma scintigraphy was further validated by the investigation through the biodistribution study. Additionally, the key findings of the pharmacokinetic study revealed C_max, T_max, AUC_0-t, AUC_0-∞, T_1/2 and K_e was found to be 163.95 ± 2.64 ng/ml, 240 ± 2.1 min, 17.75 ± 1.08 ng.hr/ml, 18.82 ± 2.51 ng.hr/ml, 70.71 ± 0.115 min, 0.098 ± 0.01 h^-1 respectively. Lastly, investigations such as weight variation and histopathological proved the plausible potential of naloxone-loaded solid-lipid nanoparticles in terms of safety as no toxicity was noticed even after the administration of the three-folds dose of the normal dose. Therefore, considering all these findings, it could be easy to say that these developed naloxone-loaded solid-lipid nanoparticles could be administrated via intranasal route and can act as successful novel nanoformulation for the effective treatment of opioid overdose.

Intranasal solid lipid nanoparticles for management of pain: A full factorial design approach, characterization & Gamma Scintigraphy

Pain is a noxious stimulus caused due to tissue damage and varies from mild to severe. Nalbuphine (NLB) is an approved, inexpensive, non-controlled, opioid agonist/antagonist analgesic used worldwide in various clinical settings for pain management. The current study aims to formulate NLB loaded solid lipid nanoparticles (SLNs) using solvent injection technology. The morphological and chemical structure of the developed SLNs were characterized using Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM) and Fourier Transformation Infrared Spectroscopy (FTIR). The results revealed from the point prediction confirmation in design expert software was the formulation of NLB-SLNs with an average particle size of (170.07 ± 25.1 nm), encapsulation efficiency (93.6 ± 1.5%) & loading capacity of 26.67%. The in-vitro permeation of developed NLB-SLNs was observed to be 94.18% at 8 h when compared with NLB solution whose maximum permeation was seen within 3 h of application. Efficacy of the formulation was also evaluated using eddy's hot plate method, where the onset of action started within 10 min of administration, and the maximum effect was observed at 1 h. The NLB-SLNs was screened for cytotoxicity in human embryonic kidney cells (HEK-293), and the dosage was considered safe when administered intranasally in animal since no detectable effect to the brain was observed. Biodistribution and gamma scintigraphy study of NLB-SLNs showed the prepared formulation reaching the target site, i.e. brain and was retained. Conclusively, the prepared NLB-SLNs formulation was safe and effective in producing an analgesic effect in vivo.

Chitosan Coated Luteolin Nanostructured Lipid Carriers: Optimization, In Vitro-Ex Vivo Assessments and Cytotoxicity Study in Breast Cancer Cells

In the present study, luteolin (LTN)-encapsulated chitosan (CS) coated nanostructured lipid carriers (NLCs) were formulated using the melt emulsification ultrasonication technique. NLCs were optimized by using the 33-QbD approach for improved in vitro efficacy against breast cancer cell lines. The optimized LTN-CS-NLCs were successfully characterized by different in vitro and ex vivo experiments as well as evaluated for cytotoxicity in MDA-MB-231 and MCF-7 cell lines. The prepared LTN-CS-NLCs showed particle size (PS), polydispersity index (PDI), and entrapment efficiency (%EE) in the range between 101.25 nm and 158.04 nm, 0.11 and 0.20, and 65.55% and 95.37%, respectively. Coating of NLCs with CS significantly increased the particle size, encapsulation efficiency, and zeta potential changes positively. Moreover, slow-release rate of LTN was achieved during 24 h of study for LTN-CS-NLCs. In addition, optimized LTN-CS-NLCs showed significantly higher mucoadhesion, gastrointestinal stability, and intestinal permeation compared to non-coated LTN-NLCs and LTN suspension. Furthermore, LTN-CS-NLCs showed statistically enhanced antioxidant potential as well as dose and time-dependent cytotoxicity against MDA-MB-231 and MCF-7 cells compared to uncoated LTN-NLCs and pure LTN. On the basis of the above findings, it may be stated that chitosan-coated LTN-NLCs represents a great potential for breast cancer management.

Quality by Design Adapted Chemically Engineered Lipid Architectonics for HIV Therapeutics and Intervention: Contriving of Formulation, Appraising the In vitro Parameters and In vivo Solubilization Potential

The present research encompasses a quality by design approach for fabricating lipid architectonics (LA) of an antiretroviral drug (Elvitegravir: EVR) to overcome inherent challenges of EVR to curtail its bioavailability issues. Comparative development strategy employing Box-Behnken design was undertaken between high-pressure homogenization technique and melt emulsification followed by probe sonication method, wherein the later was selected for engineering the EVR-LA. Particle size, entrapment efficiency and drug loading for EVR-LA were 84.6 ± 2.3 nm, 90.7 ± 1.8% and 8.9 ± 0.7% respectively. In vitro release studies established the supremacy of EVR-LA when compared with drug suspension (EVR-DS) by having a cumulative drug release of 96.89 ± 2.5% in pH 1.2, 89.84 ± 2.4% in pH 6.8 and 86.64 ± 2.5% in pH 7.4. Gut permeation studies revealed 19-fold increment in permeation by EVR-LA attributable to intrinsic permeation enhancing and efflux protein inhibitory activity of the lipids and surfactants incorporated. The result was validated by confocal study which exhibited enhanced permeation by EVR-LA. Dissolution study, conducted in fasted state simulated intestinal fluid (FaSSIF) and fed state simulated intestinal fluid (FeSSIF) media to ascertain the effect of food, demonstrated boosted absorption from FeSSIF media. Stability study was conducted in SGF pH 1.2, FaSSIF and FeSSIF media. The lipolysis study, conducted to determine in vivo fate of EVR, revealed 27-fold increment in solubilization potential from EVR-LA (72.43 ± 2.6%). Thus, EVR-LA exhibited remarkable in vitro results by improving gut permeation and solubilization fate along with enhanced lymphatic uptake, thereby leading to prospective in vivo fate.

Influence of formulation variables on miconazole nitrate-loaded lipid based nanocarrier for topical delivery

The purpose of this study was to develop miconazole nitrate (MN) based solid lipid nano-carrier formulae for topical delivery to enhance its antifungal effectiveness. Miconazole nitrate loaded Solid lipid nanoparticles (MN-SLNs) were formulated using a high shear homogenization technique characterized by particle size, polydispersity index (PI), trapping efficiency (EE percent), drug loading (DL percent) and zeta potential (ZP) characteristics. Furthermore, the optimized formulae were investigated for in-vitro release, ex-vivo study, skin toxicity test, and antifungal activity. With a particle size range of 244.2 ± 27.2 nm to 493.6 ± 35.3 nm, the selected MN-SLNs were spherical shaped. A high EE product percentage ranging from 79.38 ± 2.35 percent to 95.92 ± 6.12 percent and Zeta potential ZP values ranging from-21.6 ± 7.05 mV to-31.4 ± 6.84 mV suggesting strong stability was achieved. A controlled release of MN from the SLNs up to 48 h was shown in-vitro release study. The ex-vivo study showed that the selected MN-SLN (F4) mixture exhibited higher MN flux in the skin than a 1% MN solution. Moreover, selected MN-SLN (F4) has demonstrated a higher zone of inhibition against Candida albicans than a simple drug solution. MN-SLN (F4) had the lowest toxicity value for the skin. Besides, the MN-SLNs (F4) substantially reported antifungal activity with the least histopathological improvements compared to MN-solution utilizing immune-suppressing albino rats with induced candidiasis fungal infection. It can be fulfilled that SLNs can be acquired as a promising carrier for topical delivery of poorly soluble MN.

Docetaxel-loaded solid lipid nanoparticles prevent tumor growth and lung metastasis of 4T1 murine mammary carcinoma cells

BACKGROUND

Metastasis causes the most breast cancer-related deaths in women. Here, we investigated the antitumor effect of solid lipid nanoparticles (SLN-DTX) when used in the treatment of metastatic breast tumors using 4T1-bearing BALB/c mice.

RESULTS

Solid lipid nanoparticles (SLNs) were produced using the high-energy method. Compritol 888 ATO was selected as the lipid matrix, and Pluronic F127 and Span 80 as the surfactants to stabilize nanoparticle dispersion. The particles had high stability for at least 120 days. The SLNs' dispersion size was 128 nm, their polydispersity index (PDI) was 0.2, and they showed a negative zeta potential. SLNs had high docetaxel (DTX) entrapment efficiency (86%), 2% of drug loading and showed a controlled drug-release profile. The half-maximal inhibitory concentration (IC₅₀) of SLN-DTX against 4T1 cells was more than 100 times lower than that of free DTX after 24 h treatment. In the cellular uptake test, SLN-DTX was taken into the cells significantly more than free DTX. The accumulation in the G2-M phase was significantly higher in cells treated with SLN-DTX (73.7%) than in cells treated with free DTX (23.0%), which induced subsequent apoptosis. TEM analysis revealed that SLN-DTX internalization is mediated by endocytosis, and fluorescence microscopy showed DTX induced microtubule damage. In vivo studies showed that SLN-DTX compared to free docetaxel exhibited higher antitumor efficacy by reducing tumor volume (p < 0.0001) and also prevented spontaneous lung metastasis in 4T1 tumor-bearing mice. Histological studies of lungs confirmed that treatment with SLN-DTX was able to prevent tumor. IL-6 serum levels, ki-67 and BCL-2 expression were analyzed and showed a remarkably strong reduction when used in a combined treatment.

CONCLUSIONS

These results indicate that DTX-loaded SLNs may be a promising carrier to treat breast cancer and in metastasis prevention.

Development of Halobetasol-loaded nanostructured lipid carrier for dermal administration: Optimization, physicochemical and biopharmaceutical behavior, and therapeutic efficacy

Halobetasol propionate (HB) is considered a super potent drug in the group of topical corticosteroids. HB has anti-inflammatory activity, vasoconstriction properties, and due to its high skin penetration, it can cause systemic side effects. To improve its characteristics, enhance topical effectiveness and reduce penetration to systemic circulation, a study to optimize and characterize a HB-loaded lipid nanocarrier (HB-NLC) has been made by high-pressure homogenization method. The formulation is composed by HB, surfactant, glyceryl distearate and capric glycerides. The optimized HB-NLC containing 0.01% of HB and 3% of total lipid shows an average size below 200 nm with a polydispersity index ≪0.2 and an encapsulation efficiency ≫90%. The in vitro and in vivo tests indicate that the HB-NLC is not toxic, is well tolerated and has an anti-inflammatory effect because they decrease the production of Interleukins in keratinocytes and monocytes. HB-NLC is considered an alternative treatment for skin inflammatory disorders.

Development, Optimization, and In Vitro/In Vivo Characterization of Enhanced Lipid Nanoparticles for Ocular Delivery of Ofloxacin: the Influence of Pegylation and Chitosan Coating

This study aims to investigate whether modification of solid lipid nanoparticles (SLNs) with chitosan (CTS) and polyethylene glycol (PEG) coatings enhances corneal retention time and transcorneal bioavailability. Ofloxacin (OFLOX) was selected as the model drug because of its potential benefits for the treatment of local eye infections. The OFLOX-CTS-PEG-SLN was prepared by a modified emulsion/solvent evaporation technique. A central composite design was implemented to investigate the influence of total lipid/drug ratio, surfactant concentration, PEG stearate concentration in the lipid mixture, and CTS concentration on size, entrapment, transcorneal permeation, and adhesion to the corneal mucosal membrane. The optimized OFLOX-CTS-PEG-SLN was characterized for OFLOX cumulative percentage released in simulated tear fluid and permeated across the excised bovine corneal membrane. Moreover, nanoparticle morphology, eye irritation via histopathological analysis, and OFLOX concentration in the ocular fluids and tissues were determined. A total lipid/drug ratio of 19:1, Tween 80 of 2%, PEG stearate concentration in the lipid mixture (% w/w) of 2.6%, and CTS concentration (% w/v) of 0.23% produced 132.9 nm particles entrapping 74.8% of the total drug added. The particles detached from the corneal membrane at a force of 3700 dyne/cm². The %OFLOX released from the optimized nanoparticles was 63.3, and 66% of the drug permeated after 24 h. Compared to Oflox® drops, the optimized OFLOX-CTS-PEG-SLN exhibited similar tolerability but two- to threefold higher concentrations in the eyes of rabbits. Coating of SLN with chitosan and PEG augments the ocular bioavailability of OFLOX by increasing transcorneal permeation and enhancing mucoadhesion strength.