Dissolution and antioxidant potential of apigenin self nanoemulsifying drug delivery system (SNEDDS) for oral delivery.

Self-nanoemulsifying drug delivery systems (SNEDDS) have been used to improve the oral bioavailability of various drugs. In the current study, apigenin was developed as SNEDDS to solve its dissolution problem and enhance oral bioavailability and antioxidant potential. SNEDDS were prepared by mixing Gelucire 44/14, Tween 80, and PEG 400 under controlled conditions. The droplet of diluted SNEDDS demonstrated a spherical shape with a size of less than 100 nm and a neutral charge. The very fast self-emulsification was obtained within 32 s, and the transmittance values exceeded 99%. The highest drug loading was 90.10 ± 0.24% of the initial load with the highest %encapsulation efficiency of 84.20 ± 0.03%. FT-IR and DSC spectra showed no interaction between components. The dissolution in buffer pH 1.2, 4.5, and 6.8 showed significantly higher dissolved apigenin than the apigenin coarse powder. The dissolution profiles were fitted to the Korsmeyer-Peppas kinetics. The cellular antioxidant activities in Caco-2 cells were approximately 52.25-54.64% compared to no treatment and were higher than the apigenin coarse powder (12.70%). Our work highlights the potential of SNEDDS to enhance the dissolution and permeability of apigenin and promote antioxidant efficacy, which has a strong chance of being developed as a bioactive compound for nutraceuticals.

Enhanced stability and skin permeation of ibuprofen-loaded solid lipid nanoparticles based binary solid lipid matrix: Effect of surfactant and lipid compositions.

Hypothesis: The type of emulsifier selected has an impact on the physicochemical properties of solid lipid nanoparticles (SLNs). This study was designed to compare the effects of emulsifiers on the physicochemical properties and in vitro skin performance of SLNs prepared from a binary mixture of Softisan® 378 (S378) and cetyl palmitate (CP) to those of SLNs prepared from only CP and S378. Experiments: SLNs were prepared from CP, S378, or a binary mixture of CP and S378 (1:1 w/w) as the lipid phase and stabilized with Tego®Care 450 (TG450) or poloxamer 188 (P188) containing 1.0% w/w ibuprofen loading. The physicochemical properties including the particle size, polydispersity index (PDI), zeta potential (ZP), encapsulation efficiency (E.E.), crystallinity (%CI), and polymorphism were determined after production and after storage for 180 days under different conditions. In addition, in vitro drug release and permeation through human skin was studied after production and storage at room temperature for 180 days. Finding: The particle sizes of ibuprofen-loaded SLNs (IBSLNs) stabilized with P188 (IBSLN-P188) were smaller than those of SLNs stabilized with TG450 (IBSLN-TG450) (p < 0.05). After 180 days, the particle sizes of the IBSLNs were slightly increased compared to those at the initial time but were <250 nm. The IBSLN-TG450 sample showed a higher %CI than IBSLN-P188 prepared with similar propotions of CP and S378, and ibuprofen crystals were observed in the IBSLN1-TG450 sample after storage at 4 °C for 180 days. Based on the result of the in vitro release study and the in vitro skin permeation test, the addition of S378 into the CP-matrix modified ibuprofen release and skin permeation both permeated ibuprofen through the epidermis and retained ibuprofen in the epidermis. In addition, the storage time affected the release and skin permeation of ibuprofen from the SLNs, which depended on the composition of the IBSLNs.

Topical Microemulsions: Skin Irritation Potential and Anti-Inflammatory Effects of Herbal Substances.

Microemulsions (MEs) have gained prominence as effective drug delivery systems owing to their optical transparency, low viscosity, and thermodynamic stability. MEs, when stabilized with surfactants and/or co-surfactants, exhibit enhanced drug solubilization, prolonged shelf life, and simple preparation methods. This review examines the various types of MEs, explores different preparation techniques, and investigates characterization approaches. Plant extracts and bioactive compounds are well established for their utilization as active ingredients in the pharmaceutical and cosmetic industries. Being derived from natural sources, they serve as preferable alternatives to synthetic chemicals. Furthermore, they have demonstrated a wide range of therapeutic effects, including anti-inflammatory, antimicrobial, and antioxidant activities. However, the topical application of plant extracts and bioactive compounds has certain limitations, such as low skin absorption and stability. To overcome these challenges, the utilization of MEs enables enhanced skin absorption, thereby making them a valuable mode of administration. However, considering the significant surfactant content in MEs, this review evaluates the potential skin irritation caused by MEs containing herbal substances. Additionally, the review explores the topical application of MEs specifically for herbal substances, with an emphasis on their anti-inflammatory properties.

Influence of the emulsifier on nanostructure and clinical application of liquid crystalline emulsions.

Liquid crystals are appealing in pharmaceutical and cosmetic fields due to their unique structures that combine the properties of both liquid and solid states. Forming an emulsion into liquid crystals can be affected by a number of factors, including the emulsion composition and temperature. Changing the types and concentrations of surfactants could be another factor that affects liquid crystals. Currently, most liquid crystal research focuses on the nanostructure of liquid crystal systems without evaluating the efficacy of liquid crystals clinically. In this study, liquid crystalline emulsions made from camellia seed oil with four different surfactants (Olivem 1000, Polyaquol-2W, Nikkomulese LC, and Lecinol S-10 with Tween 80) were created. The liquid crystal emulsions were formulated in the form of oil-in-water (o/w) emulsions with Camellia oleifera seed oil serving as the main ingredient in the oil phase (10% w/w). All formulations exhibited liquid crystal characteristics with lamellar structures as determined by the polarized light microscopy and small-angle X-ray scattering with supporting data of the nanostructure from wide-angle X-ray scattering and differential scanning calorimetry (DSC). They all showed good stability under normal (room temperature) and accelerated conditions (4 °C and 40 °C) in long-term storage (6 months). Using the reconstructed human epidermis as a skin model, all formulations did not cause skin irritation. In the clinical trial, all formulations were able to reduce transepidermal water loss (TEWL) and increase skin hydration immediately after application. This lasted at least 10 h. All formulations showed distinct Maltese crosses under the polarized light microscope with a positive result for liquid crystals in wide angle X-ray scattering (WAXS) and small angle X-ray scattering (SAXS) methods. Moreover, among all formulations tested, Formulation D, which contained Lecinol S-10 and Tween 80 as emulsifiers, showed the most robust interaction between the surfactant and water molecules in the lamellar structure under DSC. The formulation was stable in long-term normal and accelerated conditions. Above all, Formulation D, which was formulated with Lecinol S-10 with Tween 80, had the best clinical result, was nonirritating to the skin, and can be used as a cream base in the pharmaceutical and cosmeceutical sectors.

Cannabidiol-Loaded Nanostructured Lipid Carriers (NLCs) for Dermal Delivery: Enhancement of Photostability, Cell Viability, and Anti-Inflammatory Activity.

The aim of this study was to encapsulate cannabidiol (CBD) extract in nanostructured lipid carriers (NLCs) to improve the chemical stability and anti-inflammatory activity of CBD for dermal delivery. CBD-loaded NLCs (CBD-NLCs) were prepared using cetyl palmitate (CP) as a solid lipid and stabilized with Tego® Care 450 (TG450) or poloxamer 188 (P188) by high-pressure homogenization (HPH). The CBD extract was loaded at 1% w/w. Three different oils were employed to produce CBD-NLCs, including Transcutol® P, medium-chain triglycerides (MCT), and oleic acid (OA). CBD-NLCs were successfully prepared with an entrapment efficiency (E.E.) of 100%. All formulations showed particle sizes between 160 and 200 nm with PDIs less than 0.10. The type of surfactant and oil used affected the particle sizes, zeta potential, and crystallinity of the CBD-NLCs. CBD-NLCs stabilized with TG450 showed higher crystallinity after production and storage at 30 °C for 30 days as compared to those with P188. Encapsulation of the CBD extract in NLCs enhanced its chemical stability after exposure to simulated sunlight (1000 kJ/m2) compared to that of the CBD extract in ethanolic solution. The CBD-NLCs prepared from MCT and OA showed slower CBD release compared with that from Transcutol® P, and the kinetic data for release of CBD from CBD-NLCs followed Higuchi's release model with a high coefficient of determination (>0.95). The extent of CBD permeation through Strat-M® depended on the oil type. The cytotoxicity of the CBD extract on HaCaT and HDF cells was reduced by encapsulation in the NLCs. The anti-inflammatory activity of the CBD extract in RAW264.7 cell macrophages was enhanced by encapsulation in CBD-NLCs prepared from MCT and OA.

Influence of Vegetable Oils on In Vitro Performance of Lutein-Loaded Lipid Carriers for Skin Delivery: Nanostructured Lipid Carriers vs. Nanoemulsions.

Nanostructured lipid carriers (NLC) were prepared from solid lipid (glyceryl monostearate, GMS) and vegetable oils, including palm oil (PO), rice bran oil (RBO) or virgin coconut oil (VCO), at different ratios (95:5, 90:10 and 80:20), while nanoemulsions (NE) were prepared with sole vegetable oils. After production, the particle size of the lutein-free NLC and NE was found to be between 100 and 150 nm and increased after loading with lutein. An increase in oil loading in NLC reduced the particle size and resulted in a less ordered lipid matrix and an increase in % entrapment efficiency. From the stability study, it was observed that the types of oils and oil content in the lipid matrix had an impact on the chemical stability of lutein. Regarding the release study, lutein-loaded NE showed higher release than lutein-loaded NLC. Both NLC and NE prepared from VCO exhibited higher release than those prepared from PO and RBO, respectively (p < 0.05). In contrast, among the formulations of NLC and NE, both lutein-loaded NLC and NE prepared from RBO showed the highest permeation through the human epidermis due to the skin enhancement effect of RBO. Based on all the results, the lipid nanocarriers composed of RBO could effectively enhance the chemical stability of lutein and promote drug penetration into the skin.

Pumpkin Seed Oil-Loaded Niosomes for Topical Application: 5α-Reductase Inhibitory, Anti-Inflammatory, and In Vivo Anti-Hair Loss Effects.

Pumpkin seed oil (PSO)-loaded niosomes were prepared from Tween 20 and cholesterol by ethanol injection. Confocal microscopy showed better skin permeation and hair follicle accumulation of the niosomes compared to the PSO solution. The PSO-loaded niosomes inhibited 5α-reductase activity in DU-145 cells and hindered IL-6 activity in RAW 264.7 cells. These effects indicated the great potential of PSO-loaded niosomes to reduce hair loss. The hair scalp serum with PSO-loaded niosomes did not show irritation to reconstructed human skin. This formulation presented a significant decrease in the percentage of fallen hairs by 44.42% in the in vivo 60-second hair count experiment and a significant increase in the anagen to telogen (A/T) ratio (1.4-fold) in the TrichoScan® evaluation after 8 weeks of treatment compared to the initial conditions, indicating the promising efficacy of PSO-loaded niosomes as a natural alternative for anti-hair loss therapy.

Phyllanthus emblica Extract-loaded Transfersomes for Hair Follicle Targeting: Phytoconstituents, Characterization, and Hair Growth Promotion.

Phyllanthus emblica Linn. (PE) has been used to promote hair growth for decades. In this study, dried PE fruit powder was extracted, tested for biological activities, and loaded into transfersomes for hair follicle targeting. Before lyophilization, PE fruit powder was extracted using 2 solvent systems, water and 30% ethanol. The PE 30% ethanolic extract had higher antioxidant activity and total phenolic content than the PE aqueous extract. However, the cytotoxicity of the PE 30% ethanolic extract was higher than that of PE aqueous extract. As a result, the PE aqueous extract was analyzed using ultra-performance liquid chromatography and found that the major component of the PE aqueous extract was gallic acid. Afterward, the PE aqueous extract was tested for its potential to activate the expression of genes involved in hair growth promotion in human keratinocytes. At a non-toxic concentration (10 µg/mL), this extract promoted various growth factors comparable to 1% minoxidil. PE-loaded transfersomes were prepared to deliver the PE aqueous extract to the hair follicle. The particle size and polydispersity index of PE-loaded transfersomes were 228 nm and 0.25, respectively. After 3 months of storage, the particle size at 4°C and 30°C was 218 nm and 241 nm, respectively, which was comparable to its initial size. However, at 40°C, the particle size dramatically increased (315 nm). The fluorescent agent, rhodamine B, was used to evaluate the potential of transfersomes to target hair follicles. Rhodamine B transfersomes had better penetration and accumulation in hair follicles than rhodamine B solution. To conclude, the PE aqueous extract, mainly composed of gallic acid, can activate hair growth gene expression. The extract can be loaded into hair follicles targeting transfersomes. Thus, PE-loaded transfersomes are a promising delivery system for hair follicle targeting to promote hair growth.

One-Pot and Green Preparation of Phyllanthus emblica Extract/Silver Nanoparticles/Polyvinylpyrrolidone Spray-On Dressing.

A spray-on wound dressing has many benefits, including easy and quick administration to broad and uneven wounds, better interface with the wound site, adhesion without additional dressing, and multiple applications in a portable package. By limiting direct contact with the wound site, such a design can prevent wound damage during treatment. This study revealed a simple, one-pot synthesis of spray-on wound dressing relying on polyvinylpyrrolidone solution incorporating silver nanoparticles as a broad-spectrum antibacterial agent and wound-healing antioxidant Phyllanthus emblica extract. Silver nanoparticles were synthesized in situ using Phyllanthus emblica extract as a biogenic reducing agent. Polyvinylpyrrolidone was employed as a film-forming agent to create an adhesive hydrogel-based dressing matrix to provide moisture and establish a shielding barrier for the wound bed as well as to regulate the release of fruit extract. In vitro tests revealed that the produced dressing film had a controlled release of the fruit extract, high antioxidant activity, and a good antibacterial action against S. aureus, P. aeruginosa, E. coli, and MRSA. Additionally, a biocompatibility study has shown that both human fibroblasts and keratinocytes are unaffected by the dressing film. Based on established findings, the current spray-on solution might be a potential option for antibacterial wound dressing.

Zingiber cassumunar Roxb. Essential Oil-Loaded Electrospun Poly(lactic acid)/Poly(ethylene oxide) Fiber Blend Membrane for Antibacterial Wound Dressing Application.

The essential oil from Zingiber cassumunar Roxb. (Plai) has long been used in Thai herbal remedies to treat inflammation, pains, sprains, and wounds. It was therefore loaded into an electrospun fibrous membrane for use as an analgesic and antibacterial dressing for wound care. The polymer blend between poly(lactic acid) and poly(ethylene oxide) was selected as the material of choice because its wettability can be easily tuned by changing the blend ratio. Increasing the hydrophilicity and water uptake ability of the material while retaining its structural integrity and porosity provides moisture balance and removes excess exudates, thereby promoting wound healing. The effect of the blend ratio on the fiber morphology and wettability was investigated using scanning electron microscopy (SEM) and contact angle measurement, respectively. The structural determination of the prepared membranes was conducted using Fourier-transform infrared spectroscopy (FTIR). The release behavior of (E)-1-(3,4-dimethoxyphenyl) butadiene (DMPBD), a marker molecule with potent anti-inflammatory activity from the fiber blend, showed a controlled release characteristic. The essential oil-loaded electrospun membrane also showed antibacterial activity against S. aureus and E. coli. It also exhibited no toxicity to both human fibroblast and keratinocyte cells, suggesting that the prepared material is suitable for wound dressing application.

Formulation and Pharmaceutical Evaluation of Extemporaneous α-arbutin Creams for the Treatment of Melasma.

Concentrated 7% w/w a-arbutin cream was formulated and evaluated using O/W and W/O emulsion bases as an extemporaneous preparation for melasma treatment. Cream bases were formulated with two pH values, 4.0 and 5.5, using a hot process. The stability of the creams was studied for 60 days under three storage conditions (i.e., 2°C to 8°C, 30°C, 40°C). Cream characteristics and all aspects of product stability including physical, chemical, and microbial were investigated. Stability was defined as no dramatic change in color, viscosity, pH, and no visible microbial growth. For stability, at least 90% of the initial a-arbutin concentration quantified by stability-indicating high-performance liquid chromatography must be obtained. It was found that pH had no influence on the a-arbutin or formulations' stability. All formulations had a-arbutin remaining higher than 90% (approximately 92%) after being stored for 60 days in all storage conditions with no significant changes in pH or viscosity. All samples complied with the microbial limits test for nonsterile pharmaceutical preparation for cutaneous products. However, a color change was detected in O/W and W/O emulsions, especially at 40°C storage condition within 28 and 14 days, respectively. Drug crystals were observed in W/O emulsion stored at 2°C to 8°C. Concerning the in vitro drug release, a-arbutin was released from O/W emulsion but not from W/O emulsion. From the above results, the O/W emulsion that was developed in this study can be used as a cream base for concentrated a-arbutin as an extemporaneous preparation. The developed a-arbutin cream prepared using O/W emulsions can be used as an extemporaneous preparation with a beyond-use date of 60 days when stored at room temperature (30°C) and in the refrigerator (2°C to 8°C).

Effect of Lipid and Oil Compositions on Physicochemical Properties and Photoprotection of Octyl Methoxycinnamate-loaded Nanostructured Lipid Carriers (NLC).

This study aimed to evaluate the effect of solid lipid and oil structures on the physicochemical properties, kinetic release, photostability, and photoprotection of nanostructured lipid carriers (NLC) containing octyl methoxycinnamate (OMC). OMC was used as a model compound since it is an effective sunscreen agent and is widely used in sunscreen products; however, it is unstable after ultraviolet radiation (UVR) exposure. OMC-loaded NLC were prepared from different solid lipids (cetyl palmitate (CP) or tristearin) and oils (caprylic/capric triglyceride, isopropyl myristate or isononyl isononanoate) at a 4:1 ratio. After production, the particle size (z-ave) and polydispersity index (PDI) of OMC-loaded NLC ranged from 190 to 260 nm and were lower than 0.25, respectively, and the zeta potential (ZP) values were higher than |50 mV|. The Fourier transform infrared (FTIR) spectroscopy results indicated no interaction among the components. Data obtained from differential scanning calorimetry (DSC) and X-ray diffraction showed that the incorporation of oil into solid lipids disturbed the crystallinity of the lipid matrix, depending on the structure of the oil molecule. OMC loaded in tristearin-based NLC (OMC-tristearin-NLC) showed higher release of OMC than OMC loaded in CP-based NLC (OMC-CP-NLC). For photostability properties, OMC-CP-NLC prepared from isononyl isononanoate showed the highest stability owing to the less-ordered structure, providing space for accommodation of OMC, whereas the percentage of OMC remaining in tristearin-based NLC was comparable. Therefore, the degree of protection was dependent on the type of solid lipid and oil. As a result, branched-chain fatty acids provided a higher degree of disturbance than linear-chain fatty acid.

Effect of Oil Content on Physiochemical Characteristics of γ-Oryzanol-Loaded Nanostructured Lipid Carriers.

Nanostructured lipid carriers (NLCs) are used as alternative carriers for many different drug delivery administration routes. They are composed of both solid lipid and liquid lipid (oil content) with both influencing their structural properties. Amounts of liquid lipid in NLCs play a role in drug release. Effect of liquid lipid (oil content) on physiochemical characteristics of NLCs related to drug-release requires detailed investigation. Here, many techniques were performed to analyze the physiochemical characteristics of NLCs, especially inside the particles. γ-Oryzanol (GO)-loaded NLCs were prepared at varying solid lipid to liquid lipid ratios. Their physicochemical properties, drug release profiles, and stability studies of prepared NLCs were investigated. Oil contents in NLCs were found to play a significant role in physiochemical characteristics related to drug release and stability, and also influence the efficiency of analytical techniques such as transmission electron microscopy (TEM) and dynamic force microscopy (DFM). Moreover, x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) gave information regarding crystallinity inside the NLCs. FTIR showed broad peaks in the range from 1184 cm-1 to 1475 cm-1 while XRD presented a broad curve indicated amorphous forms in NLCs. Orthorhombic lattices (ß' polymorph) were also elucidated by XRD and differential scanning calorimetry (DSC).

Niosomal delivery of pumpkin seed oil: development, characterisation, and physical stability.

Pumpkin seed oil (PSO) provides many health benefits including antioxidant, cardiovascular health boost, treatment of benign prostatic hyperplasia (BPH), and reduction of hair loss. The main objective of this study was to design a suitable formulation of niosomes encapsulated PSO for topical delivery. Formulation of PSO-loaded niosomes was optimised by altering the types of surfactant and the amount of PSO:surfactant:cholesterol. The developed PSO-loaded niosomes were spherical shape with the size range of 138-366 nm. The niosomes formulated with Tween 20 provided the smallest particle size. An increase in the ratio of PSO:surfactant:cholesterol from 2:2:1 to 2:4:1 led to reduction of the particle size of the niosomes. The PSO-loaded niosomes formulation F1 (PSO:Tween 20:cholesterol = 2:2:1) provided the highest percent entrapment efficacy at 75.99 ± 14.65%. The in vitro release study suggested that the release mechanism was followed Korsmeyer-Peppas. The physical stability study indicated good stability over 3 months of storage at 30 °C.

Impact of uncharged and charged stabilizers on in vitro drug performances of clarithromycin nanocrystals.

The purpose of this study was to evaluate the effect of charge on the in vitro drug performances of clarithromycin nanocrystals. To prepare different charges of nanocrystals, media milling was employed with the use of different stabilizing systems. The uncharged nanocrystals were prepared from poloxamer 407. The negatively and positively charged nanocrystals were stabilized using a combination of poloxamer 407 with sodium lauryl sulfate (SLS) and cetyltrimethylammonium bromide (CTAB), respectively. After production, the particle size of the negatively and positively charged nanocrystals was smaller than that of the uncharged one. The similar particle size of variously charged clarithromycin nanocrystals was selected to determine the in vitro drug performances. Dissolution profiles of the variously charged nanocrystals were similar; however, kinetic saturation solubility profiles were different. The positively charged nanocrystals showed higher mucoadhesiveness than the uncharged and the negatively charged nanocrystals. For drug permeation through NCI-N87 and Caco-2 cell monolayers, both charged nanocrystals showed a higher drug transport than the uncharged nanocrystals. It could be concluded that incorporating charge into clarithromycin nanocrystal formulations affected the particle size reduction process as well as the nanocrystal performances. Therefore, the surface charge is one of the crucial factors for the development of nanocrystal formulations.

Development of γ-Oryzanol Rich Extract from Leum Pua Glutinous Rice Bran Loaded Nanostructured Lipid Carriers for Topical Delivery.

Leum Pua is native Thai glutinous rice that contains antioxidants higher than white rice and other colored rice. One of the major antioxidants in rice brans is γ-oryzanol (GO). In this study, Leum Pua glutinous rice bran was extracted by different solvents. Oleic acid (~40 g/100 g extract), linoleic acid (~30 g/100 g extract), and palmitic acid (~20 g/100 g extract) were found to be major lipid components in the extracts. Methanol extract showed less variety of lipid components compared to the others. However, hexane extract showed the highest percent of γ-oryzanol compared to other solvents. Therefore, the hexane extract was selected to prepare nanostructured lipid carriers (NLC). The prepared NLC had small particles in the size range of 142.9 ± 0.4 nm for extract-loaded NLC and 137.1 ± 0.5 nm for GO-loaded NLC with narrow size distribution (PI < 0.1) in both formulations. The release profile of extract-loaded NLC formulation was slightly higher than GO-loaded NLC formulation. However, they did not follow the Higuchi model because of small amounts of γ-oryzanol loaded in NLC particles.

Fabrication and evaluation of Eudragit® polymeric films for transdermal delivery of piroxicam.

The aims of this work were to develop and characterize the prolonged release piroxicam transdermal patch as a prototype to substitute oral formulations, to reduce side effects and improve patient compliance. The patches were composed of film formers (Eudragit®) as a matrix backbone, with PVC as a backing membrane and PEG200 used as a plasticizer. Results from X-ray diffraction patterns and Fourier transform-infrared spectroscopy indicated that loading piroxicam into films changed the drug crystallinity from needle to an amorphous or dissolved form. Piroxicam films were prepared using Eudragit® RL100 and Eudragit® RS100 as film formers at various ratios from 1:0 to 1:3. Films prepared solely by Eudragit® RL100 showed the toughest and softest film, while other formulations containing Eudragit® RS100 were hard and brittle. Drug release kinetic data from the films fitted with the Higuchi model, and the piroxicam release mechanism was diffusion controlled. Among all formulation tested, Eudragit® RL100 films showed the highest drug release rate and the highest drug permeation flux across human epidermal membrane. Increasing drug loading led to an increase in drug release rate. Eudragit® can be used as a film former for the fabrication of piroxicam films.

Effect of binary solid lipid matrix of wax and triglyceride on lipid crystallinity, drug-lipid interaction and drug release of ibuprofen-loaded solid lipid nanoparticles (SLN) for dermal delivery.

HYPOTHESIS: The physicochemical properties of solid lipid nanoparticles (SLN) depend on lipid compositions. An addition of secondary solid complex triglycerides (Softisan 378; S378) into solid wax (cetyl palmitate; CP) is expected to influence the properties of obtained SLN compared to SLN prepared from sole CP. EXPERIMENTS: Ibuprofen-loaded SLN (IBSLN-TG) composed of different ratios of CP and S378 were prepared and evaluated in term of size, zeta potential (ZP), entrapment efficiency (E.E.), crystallinity, lipid-drug interaction and in vitro drug release. FINDINGS: After production, all developed IBSLN-TG prepared from different ratios of CP and S378 had the particle size in the nanometer range (180-200nm) with the ZP values of higher than |-40mV| and possessed approximately 100% E.E. The release of IBSLN-TG demonstrated the biphasic pattern with a fast release followed by sustained release, which was fitted to Higuchi's kinetics. The addition of S378 into CP-matrix led to a slight decrease in particle size and surface charge, and distortion of CP crystallization. The results from 1H-NMR indicated the formation of tiny liquid S378 nanocompartments within CP-matrix. The localization of ibuprofen in the S378 nanocompartments and the interaction between ibuprofen and S378 had an impact on the release profiles of IBSLN-TG depending on the ratios of CP and S378.

Preparation and optimization of chlorophene-loaded nanospheres as controlled release antimicrobial delivery systems.

Chlorophene-loaded nanospheres with various formulation parameters were evaluated. The optimal formulation was found at 0.1% w/v of poloxamer 407, 15 mL of ethyl acetate and 20% initial chlorophene loading that provided the suitable size (179 nm), the highest loading content (19.2%), encapsulation efficiency (88.0%) and yield (91.6%). Moreover, encapsulation of chlorophene in nanospheres was able to prolong and sustain drug release over one month. Chlorophene-loaded nanospheres were effective against Staphylococcus aureus (S. aureus) and Candida albicans (C. albicans), the main cause of hospital-acquired infections. Chlorophene-loaded nanospheres were effective against S. aureus (>46 µg/mL) and C. albicans (>184 µg/mL). These nanospheres appeared to have profound effect on the time-dependent hemolytic activity due to gradual release of chlorophene. At the concentration of 46 µg/mL, nearly no HRBC hemolysis in 24 h compared to 80% of hemolysis from free drug. In conclusion, polymeric nanospheres were successfully fabricated to encapsulate chlorophene which can eliminate inherent toxicity of drugs and have potential uses in prolonged release of antimicrobial.

Q10-loaded NLC versus nanoemulsions: stability, rheology and in vitro skin permeation.

In this study, nanoemulsions (NE) of medium chain triacylglycerols (MCT) and nanostructured lipid carriers (NLC) of cetyl palmiate/MCT were produced to load coenzyme Q(10) (Q(10)) and characterized for their stability before and after incorporation into xanthan gum hydrogels. After storage at 4, 25 and 40 degrees C, the particles remained in the nanosize range for 12 months, with zeta potential higher than |40 mV|. Similar results were found in xanthan gum-based hydrogels containing NE or NLC. The crystallinity index of Q(10)-loaded NLC increased after being incorporated into hydrogels. The Q(10) entrapped in NLC and NE remained higher than 90% at all temperatures for 12 months but dramatically decreased when exposed to light. From the rheological studies, both NLC and NE dispersions possessed pseudoplastic flow having more liquid characteristics, whereas NLC and NE hydrogels exhibited plastic flow with thixothopy, showing more elastic rather than viscous properties. The occurrence of a spatial arrangement of lipid molecules was observed in the matrix of NLC when entrapped into hydrogels. From in vitro permeation studies, it could be stated that the amount of Q(10) released and occlusiveness were major keys to promote the deep penetration of Q(10) into the skin.