Sucrose Laurate Research Articles

Efficient Delivery and Distribution in Skin of Chlorogenic Acid and Resveratrol Induced by Microemulsion Using Sucrose Laurate

To achieve efficient skin delivery of polyphenols, we prepared a novel oil-in-water (o/w)-type microemulsion (MESL) using sucrose laurate as a surfactant and ethanol, isopropyl myristate and water as other components. We examined its usefulness by in vitro studies on skin delivery of chlorogenic acid and resveratrol as hydrophilic and hydrophobic polyphenols using Yucatan micropig skin, and also examined the difference in the distribution of these polyphenols in skin. MESL significantly improved skin incorporation of these polyphenols at all time points examined (6, 20, 40 h) in the epidermis and at 20 and 40 h in the dermis, compared with the microemulsion using Tween 80 as a surfactant component (MEK), although the solubilization capacity of MESL was lower than that of MEK. Using MESL, the incorporation amount in the dermis of each polyphenol increased with time, while the amount in the epidermis was almost constant during the time examined. Incorporation efficiencies into skin of chlorogenic acid and resveratrol induced by MESL at 40 h after application were about 6-fold and 19-fold higher in the epidermis and 3.5-fold and 15-fold higher in the dermis, respectively, than those by MEK. The increase was more prominent for resveratrol. Hydrophilic chlorogenic acid was distributed slightly more in the epidermis, while hydrophobic and smaller-molecular-weight resveratrol was mainly distributed in the dermis. These findings suggest that MESL could be a promising vehicle for the efficient skin delivery of chlorogenic acid and resveratrol, especially for resveratrol to the dermis.

Sucrose laurate-enhanced transcutaneous immunization with a solid-in-oil nanodispersion

A novel transcutaneous immunization system was developed using a solid-in-oil (S/O) nanodispersion, consisting of a nano-sized particle of a protein–surfactant complex dispersed in an oil vehicle. Permeability of the model antigen protein, ovalbumin, was enhanced by coating with sucrose laurate, which is a hydrophobic surfactant. The nanodispersion prepared with sucrose laurate induced a 5-fold increase in mouse antigen-specific antibody production compared with that observed using sucrose erucate, indicating that stability of the S/O nanodispersion in the epidermis plays a key role in enabling effective immunization. In spite of the coating with the surfactants, only fluorescence-labeled ovalbumin permeated the deep epidermis beneath the stratum corneum and was observed by laser scanning confocal microscopy. These findings will lead the way to an improved transcutaneous immunization system based on S/O nanodispersion.

Preparation, Characterization and Anti-Inflammatory Activity of Swietenia macrophylla Nanoemulgel

The advances in knowledge about production and stability of dispersed systems enable the development of differentiated vehicles such as nanoemulsions and nanoemulgels, which have been effectively used to increase the bioavailability and improve the stability of the active ingredients. Nowadays there is an intensely usage of natural bioactive materials as medicinal agent in pharmaceutical industries. Swietenia macrophylla oil is used due to the bioactivity of different parts of the plant as anti-inflammatory, anti-mutagenicity, anti-tumor. SM oil Nanoemulgels were prepared by incorporating nanoemulsion with hydrogel. First by preparing mixtures of oil, glycerol with sucrose ester (Laurate, Oleate and Palmitate) to produce pre-nanoemulsion using phase inversion technique, then nanoemulsion was produced using self-emulsification technique. After that, hydrogel was added to nanoemulsion to produce nanoemulgel. It was found that 50% oil with sucrose laurate 20% and 30% glycerol was able to produce pre-nanoemulsion, and then it was diluted with water under gentile agitation to produce nanoemulsion with droplets size 114 nm, low size distribution 0.163 and low zeta potential -43.1 mV. The optimal nanoemulsion formulation was mixed with different grades of hydrogel Carbopol 934 and 940 to produce nanoemulgels. It was found that Carbopol showed no influence on the oil droplets size with a range from 113 to 117 nm, size distribution from 0.155 to 0.163 and zeta potential range from -43.4 to -44.6 mV. In addition, it was able to produce a stable nanoemulgel at different temperatures 4°C, 25°C and 40°C when stored for one year and showed priority as thickening agent in relation to texture and rheological properties when compared to Carbopol 934. The anti-inflammatory test using carrageen an induced rat paw edema method for Swietenia macrophylla oil was carried and it was found that the inflammation inhibition of SM oil was higher for nanoemulgel compared to oil solution.

Evaluation of Shirasu Porous Glass (SPG) membrane emulsification for the preparation of colloidal lipid drug carrier dispersions

Aqueous colloidal drug carrier dispersions based on nonpolar lipids are usually prepared by high energy dispersion techniques, like high-pressure homogenization. Homogenization generates high shear forces and may thus not be suitable for the processing of sensitive pharmaceutical ingredients, e.g., proteins. This study investigated the general possibility to prepare lipid nanoparticle dispersions by direct and premix Shirasu Porous Glass (SPG) membrane emulsification as alternative low energy and low shear method. The influence of different emulsifiers (polysorbate 20, sorbitan oleate, poloxamer 188, sodium dodecyl sulfate, sucrose laurate), the type of lipid phase (medium chain triglycerides, soybean oil, trimyristin, glyceryl behenate, lauroyl macrogolglycerides), the pore size of the SPG membrane (0.1, 0.2, 0.3, 0.5, 1.1μm) and the emulsifying pressure on the particle size of the resulting dispersions was investigated. The particle size was primarily controlled by the pore size of the membrane and the emulsifying pressure. Very narrow particle size distributions with membrane pore size/mean particle size ratios of 1:0.4–1:8.2 and 1:0.4–1:2.1 were observed for the direct and the premix membrane emulsification method, respectively. Due to the comparatively lower process pressures of at maximum 10bar SPG membrane emulsification is an interesting alternative method to high-pressure homogenization.

Characterization of Water/n-Propanol/Nonionic Surfactant/ Phenylacetylene Microemulsions

Water/ n- propanol/nonionic surfactant / phenylacetylene micellar systems were formulated and used for the hydration of phenylacetylene . The ratio (w/w) of n- propanol/surfactant equals 2/1. The surfactants were sucrose laurate (L1695) and Marlipal 24/70 (M2470). The extent of the micellar region as function of temperature was determined. The particle hydrodynamic diameters of the oil-in-water micellar systems measured using dynamic light scattering and were found to decrease with temperature for sucrose laurate and to increase for Marlipal 24/70 based systems. In the diluted region microemulsion systems were observed. Highly efficient hydration of phenylacetylene was performed in these microemulsions. The reaction results indicate that hydration of phenylacetylene is more efficient when sucrose laurate was used for the formulation of the microemulsions

Combined effects of nisin, sucrose laurate ester and pressure-assisted thermal processing to inactivateBacillus amyloliquefaciensspores

The objective of this work was to study the effect of nisin, alone or combined with sucrose laurate ester (SL), on enhancing Bacillus amyloliquefaciens Fad 82 spores inactivation by pressure-assisted thermal processing (PATP). Spores of B. amyloliquefaciens (108 CFU ml−1) were suspended in sterile phosphate buffer saline (pH 7.6) with concentrations of nisin (0, 100, 200, 1000, 1500 and 2000 IU ml−1) and 1.0% of SL, and combinations of nisin (1000, 1500 and 2000 IU ml−1) and SL (1.1%), and treated by PATP (700 MPa and 105 °C, for 1 min). Nisin did not show any synergetic effect with PATP in all the concentrations tested. Instead, 1.0% of SL alone was effective in enhancing inactivation.

Elution strategies for reversed-phase high-performance liquid chromatography analysis of sucrose alkanoate regioisomers with charged aerosol detection

A broad range of elution strategies for RP-HPLC analysis of sucrose alkanoate regioisomers with CAD was systematically evaluated. The HPLC analyses were investigated using design-of-experiments methodology and analysed by analysis of variance (ANOVA) and regression modelling. Isocratic elutions, isocratic elutions with increased flow, and gradient elutions with step-down profiles and step-up profiles were performed and the chromatographic parameters of the different elution strategies were described by suitable variables. Based on peak resolutions general resolution deviation for multiple peaks (RDm) was developed for sample-independent evaluation of separation of any number of peaks in chromatographic analysis. Isocratic elutions of sucrose alkanoates showed similar relationships between eluent acetonitrile concentration and retention time for all regioisomers of sucrose caprate and sucrose laurate, as confirmed by evaluation of the curvatures using approximate second derivatives and Kendall rank correlation coefficients. Regression modelling and statistical analysis showed that acetonitrile concentration and flow rate were highly significant for both average adjusted retention time and RDm for sucrose laurate. For both responses the effect of changes in acetonitrile concentration was larger than the effect of changes in flow rate, over the ranges studied. Regression modelling of the step-down gradient profiles for the sucrose alkanoates showed that the eluent acetonitrile concentrations were the overall most significant variables for retention time and separation. The models for average adjusted retention time of sucrose caprate and sucrose laurate showed only a few differences in the significance levels of terms, while the models for RDm showed larger differences between the sucrose alkanoates, in both the number of terms and their significance. Efficiency evaluation of elution strategies, in terms of RDm and analysis time, showed that the best results were offered by step-down gradient elution for sucrose caprate and isocratic elution with increased flow for sucrose laurate. Step-down gradient elution of sucrose caprate offered improvements in separation at similar analysis time compared to isocratic elution, with the most efficient elutions achieved with elution profile acetonitrile concentrations at 32.5% and 25%, resulting in reduction of RDm by 13–38% and reduction of analysis time by 3–9%. For sucrose laurate, isocratic elution with increased flow showed improvements in separation and reductions in analysis time compared to isocratic elution, such as elution at 37% with flow 2.0mL/min resulting in reduction of analysis time by 34% and equal RDm, while elution at 35% with flow 2.0mL/min reduced RDm by 29% and analysis time by 6%, compared to isocratic elution at 38% acetonitrile with standard flow (1.0mL/min).

Application of Quantitative 19F Nuclear Magnetic Resonance Spectroscopy in Tape-Stripping Experiments with Natural Microemulsions

The skin penetration of flufenamic acid (Fluf) and fluconazole (Fluc) from innovative natural microemulsions was investigated in tape-stripping experiments on pig ears. The formulations were based on the eudermic surfactants lecithin, sucrose laurate, alkylpolyglycoside or a mixture thereof. The quantification of the penetrated drug amounts was executed by (19) F nuclear magnetic resonance (NMR) in comparison with high-performance liquid chromatography (HPLC). The data obtained by the (19) F NMR method were confirmed by additional quantitative studies using HPLC. An excellent linear correlation was found for Fluf as well as for Fluc between (19) F NMR and HPLC data. This work presents a strategy outlining the use of (19) F NMR to selectively monitor the skin penetration routes of fluorinated compounds. Fluc penetrated generally well into the stratum corneum with the significantly highest amounts from the sucrose laurate microemulsion on the tape strips 1-5. Similarly, the highest amounts of penetrated Fluf could be observed from the formulation based on sucrose laurate. In addition, NMR self-diffusion studies were conducted and revealed a bicontinuous microstructure of the investigated microemulsions. The skin penetration results are in good agreement with the obtained (19) F NMR self-diffusion coefficients of the active compounds in the microemulsion systems.

Stability of CoQ10-Loaded Oil-in-Water (O/W) Emulsion: Effect of Carrier Oil and Emulsifier Type

Co-enzyme Q10 (CoQ10), a lipophilic compound that widely used in the food and pharmaceutical products was formulated in a κ-carrageenan coated oil-in-water (O/W) emulsion. In this work, we examined the solubility of CoQ10 in different carrier oils and effects of emulsifier type on the formation and stability of CoQ10-loaded O/W emulsion. Nine vegetable oils and four types of emulsifiers were used. CoQ10 was found significantly (p < 0.05) more soluble in medium chain oils (coconut oil and palm kernel oil) as compared to other vegetable oils. The O/W emulsions were then prepared with 10 % (w/w) coconut oil and palm kernel oil containing 200 g CoQ10/L oil stabilized by 1 % (w/v) emulsifiers (sucrose laurate (SEL), sodium stearoyl lactate (SSL), polyglycerol ester (PE), or Tween 80 (Tw 80)) in 1 % (w/v) κ-carrageenan aqueous solution. Particle size distribution and physical stability of the emulsions were monitored. The droplet sizes (surface weighted mean diameter, D[3,2]) of fresh O/W emulsion in the range of 2.79 to 5.83 μm were observed. Irrespective of the oil used, results indicated that complexes of SSL/κ-carrageenan provided the most stable CoQ10-loaded O/W emulsion with smaller and narrower particle size distribution. Both macroscopic and microscopic observations showed that O/W emulsion stabilized by SSL/κ-carrageenan is the only emulsion that exhibited no sign of coalescence, flocculation, and phase separation throughout the storage period observed.

The Irritant Effects of Pharmaceutically Applied Surfactants

AbstractDermal or transdermal medication may lead to irritant contact dermatitis. However, little information is available on the irritant effect of surfactants which are applied in topical formulations. Our aim was to examine the irritant effect of the most frequent compounds in topical products. A murine model was applied. The following compounds were examined: sodium lauryl sulphate (SLS), polyethoxylated (40EO) hydrogenated castor oil and sucrose laurate. SLS led to severe erythema, increase in transepidermal water loss (TEWL) and induced necrosis and accumulation of neutrophylic granulocytes and lymphocytes. Exposure to sucrose laurate resulted in an elevation of TEWL, but histology did not reveal impairment of the skin structure. Application of polyethoxylated (40EO) hydrogenated castor oil was not accompanied by tissue damage. Special attention should be paid to the irritant effect of SLS. Polyethoxylated (40EO) hydrogenated castor oil seems to be a non‐irritant agent and sucrose laurate is also a promising candidate for application in topical preparations.

Effects of Selected Polysorbate and Sucrose Ester Emulsifiers on the Physicochemical Properties of Astaxanthin Nanodispersions

The effects of selected nonionic emulsifiers on the physicochemical characteristics of astaxanthin nanodispersions produced by an emulsification/evaporation technique were studied. The emulsifiers used were polysorbates (Polysorbate 20, Polysorbate 40, Polysorbate 60 and Polysorbate 80) and sucrose esters of fatty acids (sucrose laurate, palmitate, stearate and oleate). The mean particle diameters of the nanodispersions ranged from 70 nm to 150 nm, depending on the emulsifier used. In the prepared nanodispersions, the astaxanthin particle diameter decreased with increasing emulsifier hydrophilicity and decreasing carbon number of the fatty acid in the emulsifier structure. Astaxanthin nanodispersions with the smallest particle diameters were produced with Polysorbate 20 and sucrose laurate among the polysorbates and the sucrose esters, respectively. We also found that the Polysorbate 80- and sucrose oleate-stabilized nanodispersions had the highest astaxanthin losses (i.e., the lowest astaxanthin contents in the final products) among the nanodispersions. This work demonstrated the importance of emulsifier type in determining the physicochemical characteristics of astaxanthin nano-dispersions.

Enhancement Potential of Sucrose Laurate (L-1695) on Intestinal Absorption of Water-Soluble High Molecular Weight Compounds

The potential of sucrose fatty acid esters (SEs) to enhance intestinal absorption was investigated in order to identify their utility for the intestinal absorption of water-soluble high molecular weight compounds. Fluorescein isothiocyanate-labeled dextran (FD) with a molecular weight (MW) of 4,000 (FD-4) was used as a model compound, and several SEs were tested as absorption enhancers. After FD-4 was administered intra-duodenally at 10 % (w/v) with the non-loop method in situ in rats in the absence or presence of SEs, the plasma concentration-time profiles of FD-4 were examined. As to sucrose laurate (L-1695), the relationship between concentration and enhancement effect was investigated. In addition, the enhancement effect after dosing into the different small intestinal regions, the effect on FDs with different MWs and the influence of N-acetyl-cysteine (NAC) co-existence were examined. Low water-soluble SEs exhibited slight and/or slow absorption enhancement effects, while L-1695, being highly water-soluble, had good potential to enhance the absorption rate and extent. The enhancement effect became greater as the concentration of L1695 increased. L-1695 displayed high enhancement potential in wide intestinal areas. The enhancement effect of L-1695 (10 %, w/v) depended on MWs of FDs; the mean values of the area under the plasma concentration curve from 0-120 min (AUC0-120 mins) increased by 14 and 8 times for FD-4 and FD-10 (MW 10,000), while it was hardly changed as for FD-70 (MW 70,000). The enhancement effect of L-1695 (10 %, w/v) was similar to that of sodium caprate (10 %, w/v), and was influenced to some extent by the co-existence of NAC (5 %, w/v). The absorption enhancement potential of SEs depended on their water-solubility. L-1695, being highly water-soluble, showed a good enhancement effect, and its absorption profiles were elucidated. This study proposes the possibility of SEs, in particular, L-1695, as intestinal absorption enhancers. As far as the present non-loop method is concerned, the intestinal damage was not observed macroscopically with the addition of L1695 at 2.5-20 % (w/v).

Preparation of Nanoemulsions and Solid Lipid Nanoparticles by Premix Membrane Emulsification

In an attempt to overcome problems of conventional high-energy preparation processes for colloidal drug carrier systems, premix membrane emulsification was investigated for the first time as an alternative low-energy input process for the preparation of pharmaceutical nanoemulsions and solid lipid nanoparticles. The effect of process parameters on dispersions based on nonpolar lipids (medium-chain triglycerides, soybean oil, and trimyristin) and different emulsifiers (sodium dodecyl sulfate, poloxamer 188, polyglyceryl-10-laurate, and sucrose laurate) was studied in a small-volume device and a larger scale-up approach. For emulsions and suspensions, mean particle sizes in a range from about 100 to 200 nm were observed for monomodal to monodisperse particle size distributions after 21 cycles of extrusion through polycarbonate membrane filters. As the mass ratio of matrix lipid to emulsifier (4:3, w/w concentrations) usually applied for the preparation of stable colloidal lipid particles was quite high, the amount of emulsifier in the dispersions was minimized. It was observed that the minimal concentration of emulsifier increased with decreasing membrane pore size. The possibility to prepare colloidal drug carrier systems with a high concentration of matrix lipid (up to 20%) by an optimized membrane extrusion process offers new opportunities for the processing of sensitive substances.

Natural microemulsions: Formulation design and skin interaction

Microemulsions are thermodynamically stable, colloidal drug delivery systems. This study presents the first substantiated comparison of natural, skin-compatible and biodegradable surfactants in terms of their suitability to form isotropic microemulsions and their skin interaction. Pseudoternery phase diagrams were constructed for lecithin, sucrose laurate and alkylpolyglycoside as single surfactants. Moreover, also mixed surfactant films of lecithin and alkylpolyglycoside as well as lecithin and sucrose laurate were tested. Large isotropic areas could be identified for lecithin, sucrose laurate and lecithin–sucrose laurate. One defined composition was chosen from the pseudoternery phase diagram, prepared with all investigated surfactants and 1:1 surfactant mixtures, respectively, and analysed for their effect on the stratum corneum on a molecular level by ATR-FTIR. Significantly higher frequency values of the symmetric and asymmetric CH2-stretching bands compared to the control were recorded for all microemulsions, indicating a hexagonal arrangement of the lipid chains. A similar trend was observed for the lateral packing of the alkyl chains as suggested by the shift of the CH2-scissoring bands. Moreover, diffusion cell experiments using porcine skin were performed with the two model drugs flufenamic acid and fluconazole. In both cases, the lecithin-based microemulsions showed the highest permeation rates followed by the alkylpolyglycoside–lecithin microemulsions.

Sugar Ester J-1216 Enhances Percutaneous Permeation of Ionized Lidocaine

Percutaneous absorption enhancers affect not only the permeability of skin but also the thermodynamic properties of active ingredients in the vehicle. The present study examined the effect of J-1216, a sucrose laurate with hydrophilic–lipophilic balance = 16, on the percutaneous permeation of lidocaine (LC) from this point of view. The percutaneous permeation of LC from aqueous vehicles (pH 6.0, 7.0, 8.0, and 10.0) with or without 1.5% J-1216 was examined with excised hairless mouse skin mounted on flow-through-type diffusion cell. The permeation of LC without J-1216 increased with an increase in the vehicle pH and could be basically explained by pH-partition theory. J-1216 increased the LC permeation at pH 6.0 and 7.0 but decreased it at pH 8.0 and 10.0. The interaction between LC and J-1216 was examined using an ultrafiltration technique. J-1216 micelles interacted predominantly with unionized LC. A theoretical calculation suggested that J-1216 enhances the permeability coefficient of ionized LC, whereas it has almost no effect on that of unionized free LC. J-1216 directly affects the skin to increase the permeation of ionized LC, whereas J-1216 micelles interact with unionized LC to decrease the permeation. The effect of J-1216 is therefore a function of vehicle pH and LC concentration. © 2011 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 100:4482–4490, 2011

Hydrolysis of fish oil by hyperactivated rhizomucor miehei lipase immobilized by multipoint anion exchange

Rhizomucor miehei lipase (RML) is greatly hyperactivated (around 20- to 25-fold toward small substrates) in the presence of sucrose laurate. Hyperactivation appears to be an intramolecular process because it is very similar for soluble enzymes and covalently immobilized derivatives. The hyperactivated enzyme was immobilized (in the presence of sucrose laurate) on cyanogen bromide-activated Sepharose (very mild covalent immobilization through the amino terminal residue), on glyoxyl Sepharose (intense multipoint covalent immobilization through the region with the highest amount of Lys residues), and on different anion exchangers (by multipoint anionic exchange through the region with the highest density of negative charges). Covalent immobilization does not promote the fixation of the hyperactivated enzyme, but immobilization on Sepharose Q retains the hyperactivated enzyme even in the absence of a detergent. The hydrolysis of fish oils by these hyperactivated enzyme derivatives was sevenfold faster than by covalently immobilized derivatives and three and a half times faster than by the enzyme hyperactivated on octyl-Sepharose. The open structure of the hyperactivated lipase is fairly exposed to the medium, and no steric hindrance should interfere with the hydrolysis of large substrates. These new hyperactivated derivatives seem to be more suitable for hydrolysis of oils by RML immobilized inside porous supports. In addition, the hyperactivated derivatives are fairly stable against heat and organic cosolvents.

Head group effects on molecular packing in lamellar liquid crystals

In this study, molecular packing in lamellar liquid crystals in poly(oxyethylene) dodecyl ether(C12EOn) pure systems and the two surfactant mixtures of C12EO8/1-dodecanol(C12EO0), C12EO8/lipophilic sucrose laurate (L-595), hydrophilic sucrose laurate (L-1695)/C12EO2 is investigated in terms of mean molecular area and partial molecular area (PMA). Lamellar liquid crystals formed in the C12EO8/C12EO0 mixed system show higher melting temperatures than those in the C12EOn pure systems, even though the average number of EO units in the mixed surfactant system is the same as in the pure system. We compared the mean molecular area at the interface between hydrophilic and lipophilic moieties in the lamellar liquid crystals in each system. In the mixed system, the molecules are packed more tightly than in the pure system. Among the C12EOn and sucrose laurate mixtures, the L-1695/C12EO2 mixed system showed a smaller mean molecular area per lipophilic chain than the C12EO8/L-595 mixed system. We investigated the effect of mixing two surfactants with different head group geometry on molecular packing by comparing the PMA of each surfactant.

Investigating the Stability of the Nonionic Surfactants Tocopheryl Polyethylene glycol Succinate and Sucrose Laurate by HPLC–MS, DAD, and CAD

High-performance liquid chromatography (HPLC) methods using a charged aerosol detector (CAD), a mass selective detector (MSD), and a diode array detector (DAD) were developed to characterize the nonionic surfactants d-α-tocopheryl polyethylene glycol (1000) succinate (TPGS) and Surfhope sugar ester D-1216 (sucrose laurate). The molecular structure and the heterogeneous composition resulting from different isomers and various lengths of polyethylene glycol (PEG) chains make it difficult to develop sensitive and specific analytical methods for both surfactants. Hence, there is lack of knowledge about the stability and grade of impurity of these compounds. Sucrose laurate does not possess any chromophore, thus UV detection is not applicable. Therefore, CAD and MSD have been used for determination. The aim of the study was to characterize these nonionic surfactants and to examine chemical stability at pH 1.0 and 37 °C, simulating harsh gastric conditions. It was shown that both compounds are liable to degradation under these conditions. Sucrose monolaurate exhibited a massive degradation within 8 h incubation due to cleavage of the glycosidic bondage. About 50% of sucrose monolaurate broke down, whereas a marginal amount of 3.4% (± 0.4%) of TPGS degraded into d-α-tocopheryl succinate and the associated PEG chain.

Applicability of sucrose laurate as surfactant in solid dispersions prepared by melt technology

This study focused on an investigation of the applicability of sucrose laurate as surfactant in solid dispersions. Although this surfactant has a US Drug Master File, it has not been used so far in internal pharmaceutical products. High drug-loaded solid dispersion systems consisting of gemfibrozil as a model drug and PEG 6000 as a carrier, with or without sucrose laurate (D1216), were prepared by the melting method. Cytotoxicity studies on Caco-2 monolayer cells were also performed, in order to gain information on the applicability of D1216 in oral formulations. The results showed that the presence of the surface-active agent did not affect the solid-state characteristics of the model drug significantly. A markedly improved dissolution of gemfibrozil from the ternary solid dispersion systems was observed as compared with the binary solid dispersion systems. The optimum concentration range of the D1216 in the formulations was determined to be 5–10%. The effective final concentrations of D1216 in the dissolution experiments proved to be non-toxic towards CaCo-2 cells. The results suggest the potential use of D1216 in innovative internal pharmaceutical formulations.

Full enzymatic hydrolysis of commercial sucrose laurate by immobilized-stabilized derivatives of lipase from Thermomyces lanuginosa

Sucrose laurate is a detergent that is useful for various biochemical applications because it is a green compound and is easily degradable after hydrolysis with a lipase or esterase. One problem observed in the process of sucrose laurate degradation is that most commercial detergent preparations are impure, necessitating the hydrolysis of all of the sucrose esters present in the preparation, all of them with detergent properties. In this article, a highly active catalyst, which is able to perform the hydrolysis of commercial sucrose laurate, is presented. The use of glyoxyl agarose preparations of a previously aminated Thermomyces lanuginosa lipase (TLL) enabled complete hydrolysis, in less than 30 min, of all of the compounds that comprise the mixture. In addition, this derivative is stable in the presence of 20% ethanol, which is necessary to prevent microbial contamination.