Soy Phosphatidylcholine Research Articles

Limitations of Limulus amebocyte lysate test for endotoxin control in raw materials for liposomal nanoformulations.

Aim: To evaluate the applicability of Limulus amebocyte lysate (LAL) assay for endotoxin determination in lipid compounding liposomal nanoformulations.Materials & methods: Spiked cholesterol, hydrogenated soy phosphatidylcholine and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE-PEG 2000) samples with endotoxins, simulating contaminated samples or in-process contamination were analyzed by chromogenic LAL assay.Results: Recovery of spiked endotoxins was achieved from DSPE-PEG 2000 suspended in water, whereas recovery was not achieved from spiked cholesterol and hydrogenated soy phosphatidylcholine suspended in methanol, and from multilamellar vesicles. Conclusion: Endotoxins, when in contact with organic solvents, no longer react in the LAL assay as they do in aqueous media. This indicates limitations of the LAL assay for endotoxin control in raw materials for liposomal nanoformulations.

Synergistic antimicrobial effect of daptomycin and ethyl lauroyl arginate containing self-emulsifying drug delivery system against bacterial infections

This study aimed to enhance the antimicrobial properties of daptomycin by ion-pairing with ethyl lauroyl arginate (ELA) and incorporation in a self-emulsifying drug delivery system (SEDDS).Daptomycin was ion-paired with the ELA and the hydrophobic ion pair (HIP) was loaded into SEDDS. SEDDS 1 consisted of 15% oleic acid, 5% soy phosphatidylcholine, 10% cetyltrimethylammonium bromide (CTAB) in medium-chain triglycerides (MCT) at a concentration of 250 mg/ml, 20% benzyl alcohol, and 50% PG-4 caprate. SEDDS 2 comprised 10% soy phosphatidylcholine in MCT at a concentration of 53 mg/ml, 10% CTAB, 20% benzyl alcohol, and 60% PG-4 caprate. SEDDS were characterized regarding droplet size, polydispersity index (PDI), zeta potential, and stability. Cytotoxicity was evaluated on Caco-2, HeLa, and SW620 cells. Antimicrobial activity was assessed by agar diffusion studies and time-kill assays with Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Candida albicans.Both formulations showed a droplet size below 200 nm with a PDI < 0.4, a positive zeta potential, and robust thermodynamic stability. They exhibited low toxicity profiles while maintaining full antimicrobial efficacy on all tested pathogens. Compared to unformulated daptomycin, SEDDS 1 and 2 lowered the minimum inhibitory concentration (MIC) 5- and 8- fold for S. aureus and 10- and 30- fold for S. epidermidis, respectively. Bacterial killing time was 105 -fold shortened with SEDDS 1 and 106 -fold with SEDDS 2. Furthermore, HIP and SEDDS enhanced antibacterial activity against Candida albicans and Pseudomonas aeruginosa. According to these results, ion pairing of daptomycin with ELA and incorporation into SEDDS is a promising approach to improve the antimicrobial activity of this drug.

Kinetic stability and bioavailability of curcumin nanoemulsions stabilized with krill oil phospholipids

Curcumin is a phenolic compound with widely reported bioactive properties. However, its low water solubility leads to low stability and bioavailability. Krill oil (KO) is a rich source of phospholipids naturally structured with omega-3 fatty acids (FA) that emerges as a suggested vehicle for curcumin. This study was aimed to prepare curcumin nanoemulsions (NE) using KO phospholipids as a surfactant to improve the absorption of curcumin after oral ingestion. NE were formulated with i) purified krill phospholipids (PCK), and ii) NE with crude KO without the addition of co-surfactants. As a reference, a NE was formulated using soy phosphatidylcholine (PC). Using 8 % of PCK and 4 cycles of ultrasound, NE with unimodal particle size dispersion were formed. The physicochemical analysis of the NE was monitored for 70 days at 4 and 30 °C; the nanoemulsified curcumin followed first-order degradation kinetics with a half-life (t1/2) for PC, KO, and PCK of 396, 328, and 162 days, respectively. TBARS values reached a maximum of 30 μM for KO and PCK NE, but according to the ABTS method, they had better antioxidant activities (>4.9 μM Trolox). Concerning pharmacokinetics, KO NE displayed the best bioavailability data with an AUC of 684.54 ± 72.62 ng h/mL, increasing five times more its absorption with respect to non-nanoemulsified curcumin. According to our data, NEs can guarantee the stability of curcumin during storage at 4 °C and improve its absorption after oral intake. Indeed, self-emulsified KO NEs enhance the bioavailability of curcumin to the same or better extent than soy PC conventional, but with the advantage of providing functional ingredients (omega-3 FA and astaxanthin).

The effect of the liposomal form of alteplase on the effectiveness of thrombolysis in coronary arteries in acute myocardial infarction

A liposomal (Lip) formulation of tissue plasminogen activator, alteplase (AlT), has been developed. The quantitative and qualitative composition of the liposomes, as well as their physicochemical properties and proteolytic activity, have been studied in relation to the thrombolytic liposomal form. It was determined that a formulation consisting of liposomes with a phosphatidylcholine/cholesterol ratio of 1.5 : 1, and lipids/alteplase ratio of 1 : 1, is optimal for treating acute myocardial infarction (AMI) in experimental models. At different component ratios, liposomes had a negative zeta potential value greater than 30 mV, indicating their aggregative stability, even after storage for two days at 20 degrees Celsius. Liposomes derived from soy phosphatidylcholine showed greater colloidal stability with a zeta potential of approximately –57 mV and a lower hydrodynamic diameter of approximately 140 nanometers, compared to liposomes derived from egg phosphatidylcholine, which had a zeta potential around –35.4 mV and a hydrodynamic diameter around 220 nanometers. The initial content of free AlT in the liposome supernatant from egg phosphatidylcholine (Lipeg) was 15.0 ± 4.0 %. During the incubation period of 4 days, the concentration of free AlT decreased to 9.0 ± 4.5 %. In contrast, in liposomes derived from soy phosphatidylcholine (LipS), the content of free AlT increased from 11.0 ± 4.5 % to 32.5 ± 6.0 % over the same incubation period. The value of the proteolytic activity of tissue plasminogen activator (tPA) in the compositions of Lipeg(AlT) and Lips (AlT) depends on the type of phosphatidylcholine. The initial tPA activity in Lipeg (AlT) was 36.0 %, and after 1 day, it increased to 45 %. In Lips (AlT), the initial activity was 61.0 % and increased to 66 % after 1 day. When using the liposomal form of alteplase for delivery into the coronary arteries of rats with acute myocardial infarction (AMI), a more complete fibrin lysis is noted compared to animals receiving the native form of the drug. The developed system of targeted delivery of alteplase using soy liposomes has been shown to significantly improve the degree of coronary artery lumen restoration by more than 15 %, compared to the use of a conventional drug (p &lt; 0.05).

Ultrasonicated omega‐3‐enriched skipjack tuna eyeball oil nanoliposome: preparation, characterisation, and fortification in milk

SummaryNanoliposomes (NL) containing different levels (1%, 2%, and 5%; w/w) of EPA/DHA‐enriched oil (n3FAO) from skipjack tuna eyeballs were prepared using 1%, 2.5%, and 5% (w/v) of soy phosphatidylcholine lecithin (SL) as a wall material. Then, the impact of ultrasonication at different amplitudes (40% and 50%) and sonication time (5 and 10 min) on encapsulation efficiency (EE) of selected NL was also investigated. NLs prepared without ultrasonication treatment using 2.5% SL and 2% n3FAO (WU‐NL) showed the highest EE (88%) than the remaining concentrations. When ultrasound at 40% amplitude for 5 min was applied, NLs (US‐NL) having the maximum EE of 98% were achieved. Ultrasonication employed at all conditions showed increased particle size (31.6–67.2 nm) than the WU‐NL (22.8 nm). Microstructure suggested the formation of particles with smooth surfaces and homogenous distribution. When NL powders were incorporated into the fresh cow milk at various levels (2.5% and 5.0%; w/v), likeness for aroma, mouthfeel, taste, and aftertaste slightly decreased, especially at higher levels (5%) for all samples. Nevertheless, the likeness score remained within acceptable levels (≥5.0). The fatty acid profile of the milk fortified with 2.5% (w/w) NLs showed a significant increase in polyunsaturated fatty acids (PUFAs), including EPA and DHA. Therefore, the findings indicated that ultrasonication improved the EE of liposomes, which could be successfully incorporated into milk and other food items with a lower content of PUFAs, boosting their nutritional profile while maintaining their taste and sensory attributes.

Optimizing gefitinib nanoliposomes by Box-Behnken design and coating with chitosan: A sequential approach for enhanced drug delivery.

This study aimed to improve the stability and prolonged gefitinib release from the nanoliposomes. Nanoliposomes were prepared by reverse-phase evaporation and optimized using Box-Behnken design to investigate the influence of sonication time (X 1), tween 80 / soya phosphatidylcholine ratio (X 2), and cholesterol/soya phosphatidylcholine ratio (X 3) on nanoliposomes. Optimized nanoliposomes were quasi-spherical shaped, with a mean dimension of 93.2 nm and an encapsulation efficiency of 87.56±0.17 %. Surface decoration of the optimized batch was done using different concentrations of chitosan. The optimal chitosan concentration required to adorn the nanoliposome surface was 0.01 %. In comparison to unadorned nanoliposomes (82.16±0.65 %), adorned nanoliposomes (78.04±0.35 %) released the drug consistently over 24 h via Fickian diffusion. The IC50 values for surface-adorned nanoliposomes in A549 and H1299 cells were 6.53±0.75 and 4.73±0.46 μM, respectively. Cytotoxicity of the surface-decorated nanoliposomes may be due to their higher zeta potential and prolonged drug release. At the end of the sixth month, the samples stored at 4 °C were more stable than those stored at 25 °C and 45 °C. The stability of plain nanoliposomes has increased after chitosan coating. Thus, by using different concentrations of chitosan solution as coating material, we can develop a suitable sustained drug-release surface-adorned nanoliposomal formulation. The developed nanoliposomes may offer a new path for melanoma clinics.

Fungicide-Loaded Liposomes for the Treatment of Fungal Diseases in Agriculture: An Assessment of Botrytis cinerea.

In this work, liposomes loaded with the fungicide, Fludioxonil (FLUD), for the containment of fungal diseases in agriculture were developed. Three types of vesicles with different compositions were compared: (I) plain vesicles, composed of soy phosphatidylcholine and cholesterol; (II) PEG-coated vesicles, with an additional polyethylene glycol coating; and (III) cationic vesicles, containing didodecyldimethylammonium bromide. Nanometric-sized vesicles were obtained both by the micelle-to-vesicle transition method and by the extrusion technique, and encapsulation efficiency, drug loading content, and Zeta potential were determined for all the samples. The extruded and PEGylated liposomes were the most stable over time and together with the cationic ones showed a significant prolonged FLUD release capacity. The liposomes' biological activity was evaluated on conidial germination, germ tube elongation and colony radial growth of the ascomycete Botrytis cinerea, a phytopathogenic fungus affecting worldwide many important agricultural crops in the field as well as in the postharvest phase. The extruded and PEGylated liposomes showed greater effectiveness in inhibiting germ tube elongation and colony radial growth of the fungal pathogen, even at 0.01 µg·mL-1, the lowest concentration assessed.

High-purity 1,2-dimyristoyl-sn-glycero-3-phosphocholine: synthesis and emulsifying performance evaluation.

1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) is a promising emulsifier for bioactive delivery systems, but its industrial applications are limited by the lack of cost-effective and scalable synthetic routes. The purpose of this study was to economically produce high-purity DMPC by replacing commonly used column chromatography methods and to evaluate the emulsifying performance. DMPC was synthesized from sn-glycero-3-phosphocholine using Steglich esterification followed by sequential recrystallization from ethyl acetate and acetone. The structure of DMPC was identified and its purity was confirmed using various spectroscopy and chromatography techniques. The emulsifying performance was evaluated by examining the effects of storage on the properties of o/w emulsions prepared using soybean oil with (i) soy PC, (ii) soy PC + DMPC (1:1, w/w), and (iii) DMPC as emulsifiers. The chemical impurities formed during the synthesis of DMPC was removed, and its final purity was 96%, and the melt transition temperature was 37.6°C. No visible difference between the three emulsions (soy PC, soy PC+DMPC, and DMPC) was observed during two-week storage, and the DMPC-based emulsion was more stable than soy PC emulsion, showing smaller particle size distribution during 6 months. The highly pure DMPC was synthesized by an economical method, and DMPC-based emulsions demonstrated physicochemical stable, highlighting its potential for food and pharmaceutical industry-related applications. Our findings suggest that DMPC holds promise as an emulsifier with broad applications in the food industry.

Anti-EGFR immunoliposomes for cabazitaxel delivery: From formulation development to in vivo evaluation in prostate cancer xenograft model

Liposomes functionalized with monoclonal antibodies offer targeted therapy for cancer, boasting advantages like sustained drug release, enhanced stability, passive accumulation in tumors, and interaction with overexpressed receptors on cancer cells. This study aimed to develop and characterize anti-EGFR immunoliposomes loaded with cabazitaxel and assess their properties against prostate cancer in vitro and in vivo. Using a Box-Behnken design, a formulation with soy phosphatidylcholine, 10% cholesterol, and a 1:20 drug-lipid ratio yielded nanometric particle size, low polydispersity and high drug encapsulation. Immunoliposomes were conjugated with cetuximab through DSPE-PEG-Maleimide lipid anchor. Characterization confirmed intact antibody structure and interaction with EGFR receptor following conjugation. Cabazitaxel was dispersed within the liposomes in the amorphous state, confirmed by solid-state analyses. In vitro release studies showed slower cabazitaxel release from immunoliposomes. Immunoliposomes had enhanced cabazitaxel cytotoxicity in EGFR-overexpressing DU145 cells without affecting non-tumor L929 cells. Cetuximab played an important role to improve cellular uptake in a time-dependent fashion in EGFR-overexpressing prostate cancer cells. In vivo, immunoliposomes led to significant tumor regression, improved survival, and reduced weight loss in xenograft mice. While cabazitaxel induced leukopenia, consistent with clinical findings, histological analysis revealed no evident toxicity. In conclusion, the immunoliposomes displayed suitable physicochemical properties for cabazitaxel delivery, exhibited cytotoxicity against EGFR-expressing prostate cancer cells, with high cell uptake, and induced significant tumor regression in vivo, with manageable systemic toxicity.

Physicochemical Studies on Amino Acid Based Metallosurfactants in Combination with Phospholipid.

Dicarboxylate metallosurfactants (AASM), synthesized by mixing N-dodecyl aminomalonate, -aspartate and -glutamate with CaCl2, MnCl2 and CdCl2, were characterized by XRD, FTIR, and NMR spectroscopy. Layered structures, formed by metallosurfactants, were evidenced from differential scanning calorimetry and thermogravimetric analyses. Solvent-spread monolayer of AASM in combination with soyphosphatidylcholine (SPC) and cholesterol (CHOL) were studied using Langmuir surface balance. With increasing mole fraction of AASM mean molecular area increased and passed through maxima at ~60 mol% of AASMs, indicating molecular packing reorganization. Systems with 20 and 60 mol% AASM exhibited positive deviations from ideal behavior signifying repulsive interaction between the AASM and SPC, while synergistic interactions were established from the negative deviation at other combinations. Dynamic surface elasticity increased with increasing surface pressure signifying formation of rigid monolayer. Transition of monolayer from gaseous to liquid expanded to liquid condensed state was established by Brewster angle microscopic studies. Stability of the hybrid vesicles, formed by AASM+SPC+CHOL, were established by monitoring their size, zeta potential and polydispersity index values over 100 days. Size and spherical morphology of hybrid vesicles were confirmed by transmission electron microscopic studies. Biocompatibility of the hybrid vesicles were established by cytotoxicity studies revealing their possible applications in drug delivery and imaging.

Polymeric liposomes of emtricitabine employing modified pullulan—an attempt to reduce associated hepatotoxicity

Emtricitabine (FTC) a BCS class I drug, is used for HIV prevention. The high solubility of the drug is the leading cause of severe hepatotoxicity and lactic acidosis. This research focuses on the use of modified pullulan for the preparation of polymeric liposomes of FTC. Modified pullulan was synthesized using cholesterol, and succinic anhydride in a controlled chemical environment. The formation of the polymer was established through analysis of spectra. Varying the drug-polymer ratio (1:1, 1:2, and 1:3), the drug-polymer composite was loaded in the vesicular system of soya phosphatidylcholine and cholesterol. Formulations were evaluated for drug entrapment, particle size, surface morphology, and in vitro and ex vivo drug release. An in vivo study of the pure drug and the best formulation on mice was conducted for 28 days following daily oral administration to evaluate the effect on liver and hematological parameters. The best formulation was further subjected to cytotoxicity study on hepatic cell lines. Spectral analysis confirmed the formation of modified pullulan. All formulations showed high drug entrapment in the nanovesicles. The in vitro and ex vivo drug release profiles depicted a controlled release of the drug. Hematological parameters were found to be under control in the animals throughout the experimentation. A comparative histopathology study on the livers and cytotoxicity study on hepatic cell lines revealed the safety of the best formulation over the pure drug. Hence it can be concluded that polymeric liposomes of FTC can be a promising mode of delivery to overcome its limitations.

Tolnaftate-Loaded Ethosomal Gel for Topical Delivery: Formulation and In Vitro Evaluation

Abstract Objectives Tolnaftate (TOL) is used as a topical antifungal agent but has poor skin penetration. Therefore, the present study is designed to formulate an ethosomal gel of TOL to enhance drug penetration through the skin. Methods Using the cold method ethosomal formulations with different concentrations of ethanol and soy phosphatidylcholine (SPC) were formulated. The formulation of ethosomes was characterized by vesicle size, polydispersity index and zeta potential, % drug entrapment efficiency (EE), and scanning electron microscopy (SEM). The optimized ethosomal formula was incorporated in a 1% Carbopol hydrogel dosage. Evaluation of in vitro penetration of prepared gel was performed on goat skin using Franz diffusion cells and compared with conventional gel. Result The ethosomal formulation EF5 showed the highest % EE (76.82%) with a small vesicle size of 210.1 nm and was selected as the optimized formulation. The SEM result shows that the vesicles were spherical, smooth, and in the 200-nm range. In vitro, permeability study shows that steady-state flux of TOL from ethosomal and conventional gels were 6.667 and 3.685 µg/cm/h, respectively (p &lt; 0.001). It indicated that the flux of Ethosomal hydrogel (EHG) is 2.0-fold higher than conventional hydrogel (CHG); this may be due to the flexible nature of ethosomes and ethosomal core containing ethanol, which dissolves the lipid bilayer of skin and overcomes the barrier. In vitro, an antifungal study shows that the incorporation of TOL in ethosomal hydrogel retains their activity. Conclusion From the results, it was concluded that TOL topical ethosomal gel for antifungal activity will possibly be a good choice.

Unravelling the interactions between small molecules and liposomal bilayers via molecular dynamics and thermodynamic modelling

Lipid-based drug delivery systems hold immense promise in addressing critical medical needs, from cancer and neurodegenerative diseases to infectious diseases. By encapsulating active pharmaceutical ingredients – ranging from small molecule drugs to proteins and nucleic acids – these nanocarriers enhance treatment efficacy and safety. However, their commercial success faces hurdles, such as the lack of a systematic design approach and the issues related to scalability and reproducibility.This work aims to provide insights into the drug-phospholipid interaction by combining molecular dynamic simulations and thermodynamic modelling techniques. In particular, we have made a connection between the structural properties of the drug-phospholipid system and the physicochemical performance of the drug-loaded liposomal nanoformulations. We have considered two prototypical drugs, felodipine (FEL) and naproxen (NPX), and one model hydrogenated soy phosphatidylcholine (HSPC) bilayer membrane. Molecular dynamic simulations revealed which regions within the phospholipid bilayers are most and least favoured by the drug molecules. NPX tends to reside at the water-phospholipid interface and is characterized by a lower free energy barrier for bilayer membrane permeation. Meanwhile, FEL prefers to sit within the hydrophobic tails of the phospholipids and is characterized by a higher free energy barrier for membrane permeation. Flory-Huggins thermodynamic modelling, small angle X-ray scattering, dynamic light scattering, TEM, and drug release studies of these liposomal nanoformulations confirmed this drug-phospholipid structural difference. The naproxen-phospholipid system has a lower free energy barrier for permeation, higher drug miscibility with the bilayer, larger liposomal nanoparticle size, and faster drug release in the aqueous medium than felodipine. We suggest that this combination of molecular dynamics and thermodynamics approach may offer a new tool for designing and developing lipid-based nanocarriers for unmet medical applications.

Crisaborole-Enthused Glycerosomal Gel for an Augmented Skin Permeation.

Crisaborole (CB), a boron-based compound, is the first topical PDE4 inhibitor to be approved by the US Food and Drug Administration (2016) for the treatment of Atopic Dermatitis. It is marketed as a 2% ointment (Eucrisa, Pfizer). However, CB is insoluble in water; therfore, CB glycersomes were formulated to enhance its permeation flux across the skin. We developed a glycerosomal gel of CB and compared its in vitro release and permeation flux with the 2% conventional ointment. Glycerosomes were prepared using thin film hydration method employing CB, soya phosphatidylcholine, and cholesterol. The formed film was further hydrated employing a mixture of phosphate buffer pH 7.4 /glycerin solution containing varying percentages (20,30, 40, and 50 %) of glycerol. The glycerosomes obtained were characterized by their size, polydispersity index (PDI), and Zeta potential. The entrapment efficiency of the optimized formulation (F1) was determined. The in vitro release of F1 was compared with its 2% conventional ointment. F1 was further incorporated into carbopol 934 P gel. The gel was characterized by pH, viscosity, spreadability, and drug content. The permeability flux of the glycerosomal gel was compared with its 2% conventional ointment. The optimized CB glycerosomes had a vesicle size of 137.5 ± 50.58 nm, PDI 0.342, and zeta potential -65.4 ± 6.75 mV. CB glycerosomal gel demonstrated a 2.13-fold enhancement in the permeation flux. It can thereby be concluded that glycerosomes can be an effective delivery system to enhance the penetration of CB across the skin.

Development and characterization of topical ethosomal gel for improved antifungal therapeutics

The present study aimed to develop Eberconazole nitrate (EBZ)-loaded ethosomes using Central Composite Design (CCD) by the cold method. The three-factor CCD model was implemented to investigate the effect of variables on ethosome characteristics and performance. For CCD modelling, dependent and independent variables were chosen. The percentage of soy phosphatidylcholine (PC) (X1; % w/v), ethanol (X2; % v/v), and Propylene glycol (PG) (X3; % v/v) were designated as independent variables. However, the dependent variables were particle size (Y1; nm), polydispersity index (PDI) (Y2), and encapsulation efficiency (EE) (Y3; %). The level of independent variables was changed to produce a total of 17 batches (F1-F17). Formulation code F2 with particle size; 227.9 nm, PDI; 0.160 and % EE; 90 ± 0.34 % was selected as the optimized batch. The optimized batch was further incorporated into the hydrogel matrix and investigated for several physicochemical parameters. When compared to the free drug-loaded hydrogel, the ethosomes-loaded hydrogel demonstrated controlled EBZ release with higher skin permeation and skin retention of EBZ. The assessment of antifungal efficacy of the developed formulation was carried out by in vivo animal model method. In vivo studies demonstrated that EBZ-loaded ethosomal gel may alleviate fungal infection caused by a resistant strain of Candida albicans. The study showed satisfactory results, which suggest the suitability of the developed formulation for the effective treatment of fungal infection.

Development of Liposomes Loaded with Chloroaluminum Phthalocyanine for Application of Photodynamic Therapy in Breast Cancer

Chloraluminium phthalocyanine (ClAlPc) has potential therapeutic effect for the treatment of cancer; however, the molecule is lipophilic and may present self-aggregation which limits its clinical success. Thus, nanocarriers like liposomes can improve ClAlPc solubility, reduce off-site toxicity and increase circulation time. For this purpose, developing suitable liposomes requires the evaluation of different lipid compositions. Herein, we aimed to develop liposomes containing soy phosphatidylcholine (SPC), 1,2-distearoyl-sn-glycero- 3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPEPEG2000), cholesterol and oleic acid loaded with ClAlPc using the surface response methodology and the Box-Behnken design. Liposomes with particle size from 110.93 to 374.97 nm and PdI from 0.265 to 0.468 were obtained. The optimized formulation resulted in 69.09 % of ClAlPc encapsulated, with particle size and polydispersity index, respectively, at 153.20 nm and 0.309, providing stability and aggregation control. Atomic force microscopy revealed vesicles in a spherical or almost spherical shape, while the analyzes by Differential Scanning Calorimetry (DSC), Powder X-ray Diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR) suggested that the drug was adequately incorporated into the lipid bilayer of liposomes, in its amorphous state or molecularly dispersed. In vitro studies conducted in breast cancer cells (4T1) showed that liposome improved phototoxicity compared to the ClAlPc solution. ClAlPc-loaded liposomes also enhanced the production of ROS 3-fold compared to the ClAlPc solution. Finally, confocal microscopy and flow cytometry demonstrated the ability of the liposomes to enter cells and deliver the fluorescent ClAlPc photosensitizer with dose and time-dependent effects. Thus, this work showed that Box-Behnken factorial design was an effective strategy for optimizing formulation development. The obtained ClAlPc liposomes can be applied for photodynamic therapy in breast cancer cells.

Impact of formulation parameters on self-assembled liposomes (LeciPlex® III): A detailed investigation

The present study investigated the feasibility of fabricating self-assembled liposomes, LeciPlex®, a phospholipid-based vesicular nanocarrier using cationic, anionic, and nonionic stabilizers. The phospholipid investigated was soy phosphatidylcholine and the nano-precipitation method based on solvent diffusion was applied as the fabrication technique of liposomes in this study. The effects of various formulation variables, such as lipid and stabilizer concentration, total solid concentration, and solvent type on the self-assembly of vesicles were studied for physical characterization including particle size analysis, differential scanning calorimetry, viscosity, optical transmittance, transmission electron microscopy, and small angle neutron scattering. All three LeciPlex® systems exhibited a direct relationship between particle size and phospholipid concentration. The two categoric variables, solvent, and stabilizer used to prepare LeciPlex® demonstrated a significant effect on particle size for all three LeciPlex® systems. Small angle neutron scattering, and optical transmittance confirmed the formation of micellar systems at a phospholipid: stabilizer ratio of 1:2 and vesicular systems at a ratio of 2:1 for the systems stabilized with anionic and nonionic surfactants. In contrast to this, the LeciPlex® formed with the cationic stabilizer Dioctadecyldimethylammonium bromide (DODAB), formed vesicles at both ratios. From these investigations, it was clear that the formulation space for LeciPlex® was diversified by the addition of cationic, anionic, and non-ionic stabilizers.

The impact of phospholipids with high transition temperature to enhance redox-sensitive liposomal doxorubicin efficacy in colon carcinoma model

In this study, we have developed a redox-sensitive (RS) liposomal doxorubicin formulation by incorporating 10,10′-diselanediylbis decanoic acid (DDA) organoselenium compound as the RS moiety. Hence, several RS liposomal formulations were prepared by using DOPE, HSPC, DDA, mPEG2000-DSPE, and cholesterol. In situ drug loading using a pH gradient and citrate complex yielded high drug to lipid ratio and encapsulation efficiency (100%) for RS liposomes. Liposomal formulations were characterized in terms of size, surface charge and morphology, drug loading, release properties, cell uptake and cytotoxicity, as well as therapeutic efficacy in BALB/c mice bearing C26 tumor cells. The formulations showed an average particle size of 200 nm with narrow size distributions (PDI < 0.3), and negative surface charges varying from −6 mV to −18.6 mV. Our study confirms that the presence of the DDA compound in liposomes is highly sensitive to hydrogen peroxide at 0.1% w/v, resulting in a significant burst release of up to 40%. The in vivo therapeutic efficacy study in BALB/c mice bearing C26 colon carcinoma confirmed the promising function of RS liposomes in the tumor microenvironment which led to a prolonged median survival time (MST). The addition of hydrogenated soy phosphatidylcholine (HSPC) with a high transition temperature (Tm: 52–53.5°C) extended the MST of our 3-component formulation of F14 (DOPE/HSPC/DDA) to 60 days in comparison to Caelyx (PEGylated liposomal Dox), which is not RS-sensitive (39 days). Overall, HSPC liposomes bearing RS-sensitive moiety enhanced therapeutic efficacy against colon cancer in vitro and in vivo. This achievement unequivocally underscores the criticality of high-TM phospholipids, particularly HSPC, in significantly enhancing liposome stability within the bloodstream. In addition, RS liposomes enable the on-demand release of drugs, leveraging the redox environment of tumor cells, thereby augmenting the efficacy of the formulation.

Protection of bovine serum albumin through encapsulation in hybrid vesicles

This study focuses on hybrid vesicles (HVs) formed through co-assembly of soy phosphatidylcholine (SPC) and a triblock copolymer (F127). After elucidating the superior stability of HVs over the assemblies of neat SPC and F127, these were encapsulated with bovine serum albumin (BSA), as model a thermolabile protein. Characterizations were performed using dynamic light scattering (DLS), electron microscopy, circular dichroism and high-sensitivity differential scanning calorimetry. The size of HVs increased slightly at higher proportion of F127 and upon encapsulation of BSA. In spite of this, vesicles remained spherical and displayed a smooth surface. They showed superior dilution stability in comparison to neat copolymer micelles and phospholipid vesicles. Their stability can be ascribed to hydrophobic association between the phospholipid and copolymer, and manifested into increase in phase transition temperature of the former. We found that HVs could protect BSA from denaturation and unfolding when challenged by high solution temperature, pH changes and salt incorporation.

Potential Activity of Micafungin and Amphotericin B Co-Encapsulated in Nanoemulsion against Systemic Candida auris Infection in a Mice Model.

The Candida auris species is a multidrug-resistant yeast capable of causing systemic and lethal infections. Its virulence and increase in outbreaks are a global concern, especially in hospitals where outbreaks are more recurrent. In many cases, monotherapy is not effective, and drug combinations are opted for. However, resistance to antifungals has increased over the years. In view of this, nanoemulsions (NEs) may represent a nanotechnology strategy in the development of new therapeutic alternatives. Therefore, this study developed a co-encapsulated nanoemulsion with amphotericin B (AmB) and micafungin (MICA) (NEMA) for the control of infections caused by C. auris. NEs were developed in previous studies. Briefly, the NEs were composed of a mixture of 10% sunflower oil and cholesterol as the oil phase (5:1), 10% Polyoxyethylene (20) cetyl ether (Brij® 58) and soy phosphatidylcholine as surfactant/co-surfactant (2:1), and 80% PBS as the aqueous phase. The in vivo assay used BALB/c mice weighing between 25 and 28 g that were immunosuppressed (CEUA/FCF/CAr n° 29/2021) and infected with Candida auris CDC B11903. The in vivo results show the surprising potentiate of the antifungal activity of the co-encapsulated drugs in NE, preventing yeast from causing infection in the lung and thymus. Biochemical assays showed a higher concentration of liver and kidney enzymes under treatment with AmB and MICAmB. In conclusion, this combination of drugs to combat the infection caused by C. auris can be considered an efficient therapeutic option, and nanoemulsions contribute to therapeutic potentiate, proving to be a promising new alternative.