Abstract  Sjogren-Larsson syndrome (SLS) is an inherited disorder associated with deficient oxidation of long-chain aliphatic alcohols. Previous studies have reported modest elevations in total (free + esterified) fatty alcohols in SLS, but free fatty alcohols have not been selectively measured, in part because of their low concentrations in most tissues and the presence of trace fatty alcohol contaminants in some solvents used for their analysis. We adapted methods to measure free fatty alcohols in cultured cells and plasma that minimize exogenous alcohol contamination. Fatty alcohols were analyzed as acetate derivatives, using capillary column gas chromatography. By this method, cultured skin fibroblasts from SLS patients were found to have 7- and 8-fold elevations in the mean content of hexadecanol (16:0-OH) and octadecanol (18:0-OH), respectively. The mean plasma 16:0-OH and 18:0-OH concentrations in SLS patients (n = 11) were 9- and 22-fold higher than in normal controls, respectively. In SLS fibroblasts, most of the fatty alcohol (59%) that accumulated was free rather than esterified alcohol, whereas free alcohol accounted for 23% of the total alcohol in normal cells. These results indicate that elevations in free fatty alcohols provide a sensitive marker for the enzymatic defect in SLS. The ability to measure free fatty alcohols in cultured cells and plasma should prove useful for investigations of normal fatty alcohol metabolism and the deranged metabolism in SLS.

Abstract  Human prostate was used as a source of 5 alpha reductase. Compounds were incubated with an enzyme preparation and [3H]testosterone. [3H]-dihydrotestosterone production was measured to calculate 5 alpha reductase activity. IC50 values (ng/ml) were finasteride = 1; Permixon = 5,600; Talso = 7,000; Strogen Forte = 31,000; Prostagutt = 40,000; and Tadenan = 63,000. Bazoton and Harzol had no activity at concentrations up to 500,000 ng/ml. In castrate rats stimulated with testosterone (T) or dihydrotestosterone (DHT), finasteride, but not Permixon or Bazoton, inhibited T stimulated prostate growth, while none of the three compounds inhibited DHT stimulated growth. These results demonstrate that finasteride inhibits 5 alpha reductase, while Permixon and Bazoton have neither anti-androgen nor 5 alpha reductase inhibitory activity. In addition, in a 7 day human clinical trial, finasteride, but not Permixon or placebo, decreased serum DHT in men, further confirming the lack of 5 alpha reductase inhibition by Permixon. Finasteride and the plant extracts listed above do not inhibit the binding of DHT to the rat prostatic androgen receptor (concentrations to 100 micrograms/ml). Based on these results, it is unlikely that these plant extracts would shrink the prostate by inhibiting androgen action or 5 alpha reductase.

Abstract  Recovery of metabolites from fermentation broth by solvent extraction can be used to optimize fermentation processes. End-product reutilization, low product concentration and large volumes of fermentation broth and the requirements for large bioreactors, in addition to the high cost largely contributed to the decline in fermentative 2,3-butanediol production. Extraction can successfully be used for in-situ alcohol recovery in 2,3-butanediol fermentations to increase the substrate conversion. In the present work organic extraction of 2,3-butanediol produced by Klebsiella pneumoniae fermentation was studied to determine solvent effect on 2,3-butanediol production. The aim of this project was liquid-liquid extractive fermentation systems evaluation as an alternative to overcome the end product effect and to increase of 2,3-butanediol production by K. pneumoniae because Conventional fermentative production of 2,3-butanediol by K. pneumoniae has the disadvantage of product reutilization by the organism. Alternatives to overcome this problem have met with limited success. Extractive fermentation has been shown to solve this problem. An effort has been made in this study to use for the extractive fermentation of 2,3-butanediol using oleyl alcohol as extract-ant. Eighteen organic solvents were examined to determine their biocompatibility for in situ extraction of fermentation products from cultures of the K. pneumoniae. From 18 tested solvents, 13 of which were non-toxic to K. pneumoniae. The highest 2,3-butanediol production (23.01 g l(-1)) was achieved when oleyl alcohol was used. In situ removal of end products from K. pneumoniae resulted in increased productivity. In conclusion 2, 3-hutanediol productivity increased from 0.5 g l(-1)h(-1) to 0.66 g l(-1)h(-1) in extractive fermentation using oleyl alcohol as the extraction solvent.

Abstract  In this work, the potential of waxes for preparing with the ultrasonic spray congealing technique microparticles for controlling the in vitro release of verapamil HCl was investigated. The first part of the study encompassed the optimisation of the formulation to achieve an efficient drug incorporation together with a satisfactory in vitro drug release rate. In particular, microcrystalline wax, stearyl alcohol and mixtures of the two were used. Also a surfactant (soya lecithin) was added to the formulations. After the particle size analysis, the characterisation of the microparticles involved the study of the solid state of drug and carriers in the systems (DSC, HSM and XRD) and the morphological and chemical analyses of the microparticle surface (SEM and XPS). Finally, the drug release mechanism from these devices was evaluated using the statistical moment analysis. The results of this study show that by selecting the type and the amount of the carriers, microparticles with a spherical shape and a good encapsulation efficiency were observed. These particles showed a zero-order release for 8 h, without modifying the solid state properties of the drug. Therefore, waxy microparticles prepared by the ultrasonic spray congealing technique are promising solvent-free devices for controlling the release of verapamil HCl. (C) 2003 Elsevier Science B.V. All rights reserved.

Abstract  Interest in pyruvic acid has been growing due to the increase in its potential areas of use and its importance in metabolic reactions. These reasons along with the limitations on recovery have prompted researchers to consider novel recovery techniques. Reactive extraction has been proposed as a promising approach to the recovery of carboxylic acids. In this study, equilibrium and kinetic data were obtained for reactive extraction of pyruvic acid using trioctylamine (TOA) or Alamine 336 in 1-octanol or oleyl alcohol. The results showed that, without pH adjustment in the aqueous phase, and without the use of an extractant, 1-octanol extracted more pyruvic acid than oleyl alcohol with a distribution coefficient (K(D)) of 0.30. This trend remained the same when tertiary amines were used as an extractant. The K(D) values did not significantly differ with TOA or Alamine 336. The recovery of pyruvic acid was observed to increase as a function of TOA concentration and the stoichiometry of the reaction was mainly 1:1. As tertiary amines react only with undissociated acids, an increase in the initial pH of the aqueous phase lowered the KD values. When the pH was 4.0, the effect of TOA concentration on pyruvic acid extraction disappeared and for all concentration levels a distribution coefficient of 0.10 was obtained. Kinetic measurements showed that the reaction between pyruvic acid and TOA in 1-octanol is first order with respect to the two reactants with a rate constant of 0.94 L mol(-1) s(-1). The enhancement factor was calculated as 25.

Abstract  The expression of Pax-5 gene is altered in human myeloma cells (malignant plasma cells). This altered expression is considered to be closely involved in oncogenesis of human myeloma. To investigate the possible mechanism(s) underlying this alteration, we first cloned the 1,050 bp fragment in the 5' upstream region of human Pax-5 gene by PCR-mediated gene walking method. The cloned fragment has predicted regulatory motifs for Lyf-1(Ik-1), IK-2, bHLH, E-47, Sox-5, Oct-1, GATA-1,-2, and -3, but it lacks a TATA box. By constructing deletion mutants of this fragment, its basal promoter activity was analyzed by transfecting these mutants to Cos 7 cells. The maximal promoter activity was recovered by the fragment that extends between -70 to -820 upstream of the transcription start site. Also, three DNA fragments from this cloned sequence were used as templates in gel shift assay; these fragments covered most of the predicted regulatory sites. Specific binding activities were found in each DNA fragment. Therefore, we could clone the functionally active fragment of 5' upstream region of human Pax-5 gene.

Abstract  Ether lipids show high specific cytotoxicity in vitro on a wide variety of experimental tumors, but only moderate activity in vivo. One reason for this lack of activity in the whole animal might be a high degree of metabolic degradation. We therefore studied the biotransformation of 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine ([H]ET18-OMe) labeled in position 9-10 of the 1-alkyl chain, in rat plasma and erythrocytes, HL60 and K562 leukemic cells. HT29 adenocarcinoma cells, and cultured hepatocytes at 37 degrees C, and in a system of isolated and perfused rat liver. ET18-OMe and its metabolites were identified and quantified after lipid extraction and TLC separation. In tumor cells, 98% of ET18-OMe remained almost unmodified in vitro after 24-hr incubation. Plasma and erythrocytes from rats metabolized only 4-5% of the original compound in 3 hr. In cultured hepatocytes, 35% and 58.3%, respectively, of ET18-OMe was present after 6 and 24 hr as the metabolites 1-O-alkyl-2-O-methylglycerol (AMG), 1-O-alkyl-2-O-methylphosphatidic acid (AMPA), and stearyl alcohol (SA) (products of direct hydrolysis by phospholipases C and D and alkylhydrolase); phospholipids (phosphatidylcholine and phosphatidylethanolamine); and neutral lipids (products of secondary metabolism). In perfused rat liver, similar to 15% of the total radioactivity incorporated after 3 hr was distributed in metabolites as follows: 5.9% of AMPA, 5.0% of AMG, and 3.1% of SA. We conclude that the metabolism of ET18-OMe in normal tissues occurring through the same enzymes that metabolize natural lipids may partly explain the lack of effect in vivo.

Abstract  The object of this study was to prepare rosiglitazone maleate (RM) sustained-release floating microspheres and investigate their pharmacokinetics. AM microspheres were prepared with ethyl cellulose (EC) and octadecyl alcohol as the carrier materials by an emulsion-solvent diffusion method, and the properties of morphology in vitro floating capability, drug loading (DL), entrapment efficiency (EE), in vitro release and in vivo pharmacokinetics were investigated. The prepared microspheres had a completely spherical shape. The percentage of microspheres floating after 12h was (91.45 +/- 1.62)%, and the DL and EE were (9.31 +/- 0.31)% and (89.55 +/- 1.65)% respectively. Pharmacokinetic studies demonstrated that the RM floating microspheres were superior to commercial tablets in terms of the decrease in peak plasma concentration and maintenance of AM concentration in plasma. The area under the curve of plasma concentration time (AUC) of the floating microspheres was equivalent to that of reference tablets. The results showed that floating microspheres are a feasible approach for the sustained-release preparation of drugs which have limited absorption sites in the upper small intestine.

Abstract  A modified USP paddle method using minibaskets was used to study the effects of various formulations on in vitro dissolution of ibuprofen microspheres. Formulations containing waxes such as paraffin or ceresine wax without modifiers exhibited very slow dissolution profiles and incomplete release, which did not improve with increased drug loading or the preparation of smaller microspheres. The addition of modifiers such as stearyl alcohol and glyceryl monostearate greatly increased the dissolution rate, with 20% (w/w) near the optimum for predictable dissolution. Higher drug loading and decreased microsphere size increased the dissolution rate from microspheres containing modifier. Optimum formulations contained ceresine wax or microcrystalline wax and stearyl alcohol as a modifier, with a drug content of 17%. An increase in the encapsulation dispersant concentration had little effect on the dissolution profiles. The dissolution data from narrow size fractions of microspheres indicated spherical matrix drug release kinetics; the 50% dissolution time decreased with the square of the microsphere diameter. With appropriate modifiers, wax microsphere formulations of drugs with solubility characteristics similar to those of ibuprofen can offer a starting basis for predictable sustained release dosage forms.

Abstract  The dilational viscoelasticity properties of decane-water interface containing two demulsifiers with straight chain SP169 (octadecanol polyoxypropylene-polyoxyethylene ether) and branch chain AE121 (tetraethylenehexamine polyoxypropylene-polyoxyethylene ether) respectively were investigated. The dependence of dilational modulus on dilational frequency and demulsifier concentration was expounded. The influences of two demulsifiers on dilational properties of oil-water interface containing surface-active fraction from crude oil were also studied. The dynamic interfacial tensions between solutions of two demulsifiers and decane were measured and were related to the interfacial dilational rheology properties. The results showed that the two demulsifiers could decrease remarkbly the dilational modulus of oil-water interface containing surface-active fraction from crude oil. At low concentration, because of stronger adsorption ability, the effect of decreasing dilational modulus of SP169 was better. But above a certain concentration, AE121 was preferential because of its higher substitution ability. Since the interface film containing demulsifier had a certain dilational modulus itself, the dosage of demulsifier could not be much higher.

Abstract  We demonstrate the existence of an anomalous, strong attraction between small (9 nm) oleic acid-grafted magnetite particles and octadecanol-grafted silica spheres (420 nm) in apolar solvents. This attraction manifests itself by irreversible adsorption of magnetite particles onto silica spheres, with surface coverages up to 30%. This "heteroflocculation" is, quite surprisingly, orders of magnitude slower than a diffusion-limited process. The adsorption can be reversed by transferring covered silica particles to solvents with a higher dielectric constant. The findings practically rule out van der Waals forces or Coulomb forces between any pre-existing surface charges as the source of attraction.

Abstract  The study represents the first part of a series of papers on physico-chemical measurements carried out by gas chromatography. The distribution constant, the liquid film surface areas, the retention volumes corrected for the adsorption at interface, and the quadratic equation that describes the temperature dependence on retention volume for solutes in n-octadecanol as stationary phase at 65-90 degrees C are presented.

Abstract  Monolayers of straight chain and 2-methyl branched chain alcohols with alkyl chain lengths of C-10-C-18 are experimentally studied by a conventional film balance technique combined with a Brewster angle microscope (BAM). The comparison of the surface pressure (pi)-area (A) isotherms with the corresponding BAM images provides information on the phase behavior and the first-order main phase transition of the monolayers. Striking differences in the dependence of the phase transition pressure on temperature of the straight chain and 2-methyl-substituted alcohols are correlated with differences in the molecular ordering. The general conditions for the main phase transition in the corresponding homologous alcohols can be derived. The effect of alkyl chain length and 2-methyl substitution on the general textural features of the condensed phase domains is determined under equilibrium and nonequilibrium conditions. n-Alcohol monolayers form defined and well-shaped condensed phase domains, often with inner texture in equilibrium. The long-range orientational order is strongly reduced in the condensed phase of 2-methyl-alcohols. Therefore, in the two-phase coexistence region of 2-methyl-alcohol monolayers only irregularly shaped domains without any inner structure are formed, which cannot be observed at the medium alkyl chain length C-14 because of the low contrast. Model calculations of the two-dimensional lattice structure of the racemic 2-methyl-hexadecanol on the basis of the pg space group are performed and correspond well with the reduced ordering concluded from the experiments.

Abstract  Stable dispersions of monodisperse colloidal silica spheres containing a dye or fluorophore have been synthesized according to a general procedure and dispersed in polar and apolar liquids. The procedure consists of the coupling of the dye to a silane coupling agent, (3-aminopropyl)triethoxysilane, and the controllable incorporation of the reaction product into the silica sphere. The silica spheres are prepared from tetraethoxysilane in mixtures of ammonia, water, and ethanol. The composition of the silica spheres can be controlled in such a way that the organic groups can be placed on the surface, in a thin shell inside the particle or distributed through the volume of an inner core. Fluorescein isothiocyanate was used to make easily bleachable, fluorescent silica spheres. Hydrophilic charge stabilized and organophilic sterically stabilized 1-octadecanol-coated dyed silica systems were synthesized and dispersed in several solvents. All the particles were characterized after the several reaction steps by static and dynamic light scattering and transmission electron microscopy. The fluorescent spheres were further characterized by fluorescence spectroscopy and confocal scanning laser fluorescence microscopy. Great effort was taken to prepare monodisperse dispersions free of clusters of particles. Such model dispersions are required for (scattering) studies of interparticle interactions in (concentrated) systems. Therefore, the several steps of the synthesis and optical characterization are described in detail.

Abstract  A PVP/SA adduct was prepared by reacting of N-vinylpyrrolidone with stearyl alcohol in presence of ammonium persulphate as initiator in different preparation reaction conditions. The optimum conditions to prepare that adduct are VP/SA, 25%; LR, 1 I/kg; reaction temperature, 80 degrees C and reaction time, 40 min. The graft copolymerization of N-vinylpyrrolidone onto stearyl alcohol was confirmed by the FTIR analysis. The TEM image of the prepared adduct emulsion shows that its particle size ranges from 45 to 173 nm. Finishing of cotton/polyester fabric sample with easy care finishing bath containing 80 g/l of that adduct emulsion results in an increasing in the tensile strength, water repellency rating, antibacterial properties, softness degree, and stiffness along with a reduction in the resiliency of treated fabric. The surface of the prepared adduct treated fabric was characterized via scanning electron microscope. (C) 2017 Elsevier B.V. All rights reserved.

Abstract  Condensed monolayers of octadecanol have been formed on the surface of single water drops suspended in ambient air by acoustic levitation. As known from former work which has been mostly carried out on Langmuir troughs many monolayers are able to reduce remarkably the evaporation rate at the air-water interface. In contrast to Langmuir troughs, acoustic levitation offers the advantages of a minimized and contact-less technique. The surface area of an evaporating water drop suspended in ambient air declines linearly with time described by the evaporation constant K. After adding octadecanol a condensed monolayer is formed on the drop surface while the drop evaporates. During this process, the evaporation constant is scaled down by a factor of approximately 20. (c) 2007 Elsevier B.V. All rights reserved.

Abstract  In this Technical Note, the use of a liquid metal, i.e., a low melting point Pb-Sn-In-Bi alloy, as the phase change material (PCM) in thermal energy storage-based heat sinks is tested in comparison to an organic PCM (1-octadecanol) having a similar melting point of similar to 60 degrees C. The thermophysical properties of the two types of PCM are characterized, revealing that the liquid metal is much more conductive while both have nearly identical volumetric latent heat of fusion (similar to 215 MJ/m(3)). By using at the same volume of 80 mL, i.e., the same energy storage capacity, the liquid metal is shown to outperform significantly over the organic PCM under the various heating powers up to 105.3 W/cm(2). During the heating period, the use of the liquid metal leads to a remarkable extension of the effective protection time to nearly twice longer as well as a reduction of the highest overheating temperature by up to 50 degrees C. The cool-down period can also be shortened significantly by taking advantage of the much higher thermal conductivity of the liquid metal. These findings suggest that liquid metals could serve as a promising PCM candidate for particular applications where the volume limit is very rigorous and the penalty in weight increment is acceptable. (C) 2016 Elsevier Ltd. All rights reserved.

Abstract  In this work, a new thermodynamic method, based on the McMillan-Mayer solution theory, is proposed to interpret and predict the solubility of low- and high-molecular-weight compounds in compressed CO2. In the thermodynamic approach presented here, the solute is referred to as a pseudo pure component while the compressed CO2 is represented as a continuous medium that affects the interactions among solute molecules. The perturbed-hard-sphere-chain (PHSC) theory is used within the McMillan-Mayer framework to derive an expression for the repulsive and attractive contributions to the Helmholtz free energy of the solute.

While easy to handle, the model enlightens the effects of molecular weight and other physical-chemical characteristics on compounds solubility in compressed media. The thermodynamic approach fairly describes the experimental data concerning the solubility of several substances in compressed CO2 at different temperatures. The model also predicts CO2 solubility in PEG polymer and semi-quantitatively reproduces high-molecular-weight component solubility in compressed CO2 containing low amount of ethanol as co-solvent. (C) 2002 Elsevier Science B.V. All rights reserved.

Abstract  The localized surface plasmon resonance (LSPR) behavior of indium-doped ZnO (IZO) nanocrystals synthesized in different solvents was studied. 1-octadecanol, oleic acid, oleyl alcohol, oleyl amine and 1-octadecene were used as solvent(s) and co-solvent(s) in the pyrolysis synthesis of indium-doped ZnO (IZO) nanoparticles. The results showed that the nanocrystals from a solvent system consisting of 1-octadecene, 1-octadecanol, and oleic acid exhibited enhanced LSPR near-infrared radiation absorption without sacrificing transparency in the visible region. The indium-rich core verified using ICP and XPS analysis was shown to be critical for the enhancement. The reaction mechanism of solvents on the generation of indium-rich core was elucidated through a systematic study of the reaction parameters. The interaction between the activating agent, inhibiting agent and solvent, and their effect on tuning the reactivity of dopant and host precursors were important for the formation of a nanostructure with a dopant-rich core. The solvent effect was also found in the synthesis of gallium-doped ZnO and confirmed to be a general phenomenon in the preparation of doped ZnO nanoparticles.

Abstract  ES-285(.)HCl [(2S,3R)-2-amino-3-octadecanol hydrochloride] is a novel investigational anticancer agent, which has shown in vitro and in vivo cytotoxic activity against various tumor cell lines with selectivity for certain solid tumors. The pharmaceutical development of ES-285(.)HCl warranted the availability of an assay for the quantification and purity determination of ES-285(.)HCl active pharmaceutical ingredient (API) and its pharmaceutical dosage form. A liquid chromatographic method (LC) comprising of derivatisation of ES-285(.)HCl with phenylisothiocyanate and UV-detection was developed. The method was found to be linear, precise and accurate. The assay also proved selectivity as determined by analysing ES-285(.)HCl in combination with 15 analogues and in combination with hydroxypropyl-beta-cyclodextrin, the excipient used in the lyophilised pharmaceutical dosage form. Stress testing showed that the degradation products were separated from the parent compound, confirming its stability indicating capacity. The method was found robust as determined with design of experiments (DoE), which made it possible to predict system suitability responses in worst case experimental conditions and to define criteria for system suitability testing. (C) 2003 Elsevier B.V. All rights reserved.

Abstract  In this work, highly absorbent cross linked co-polymer gels of cis-9-octadecen-1-ol with acrylic/methacrylic acid and 1-hexene in different molar ratios were synthesized by thermal polymerization techniques and studied. The polymers were characterized by Fourier Transform-Infrared Spectroscopy, Thermogravimetric analysis and Scanning Electron Microscopy techniques. Their non-ionic nature was verified with the help of transport number measurement by Wagner polarization technique. The polymers were found to have very high swelling capacities in organic solvents like chloroform, tetrahydrofuran, ethanol, diethylether, thiophene, pyridine, and benzene. These gels show maximum swelling for chloroform which reaches up to 750%. The swelling capacities for different oils like kerosene, gasoline, engine oil, and silicon oil, are also favorable. The swelling kinetics confirmed that the swelling followed second order kinetics. The chloroform retention time was also checked which established that the gels can be recycled and reused again and again. An experiment showing removal of kerosene from kerosene/water mixture is also performed. This confirms that these gels can be used in removing organic contaminants and oil from water and can help in water purification and environmental cleanup purposes. (C) 2012 Elsevier Ltd. All rights reserved.

Abstract  The objectives of the paper are to verify the potentialities of a sequential two phase partitioning bioreactor in degrading xenobiotics and to evaluate the kinetic parameters for modelling the system. The target compound investigated was the 4-nitrophenol. Preliminary tests were carried out to define the solvent most appropriate for the compound. Among the three investigated solvents 1-undecanol, 2-undecanon and oleyl alcohol, the 2-undecanon was chosen because of the higher partition coefficient of 30 and the negligible formation of emulsions. Moreover, the tested solvent showed satisfactory "biocompatibility" characteristics for the biomass with minor effects on the intrinsic kinetics. Parallel batch kinetic tests were then performed with the conventional one phase and the two phase systems. In the two phase system the biomass is exposed for all the time to 4NP concentrations that are significantly lower if compared to the conventional system and, for the highest concentration (450 mg/l) in the two phase system a reduction of the reaction time is observed depending on the biomass concentration. Kinetic parameters were also evaluated in both cases by fitting of the experimental data with a modified form of the Haldane equation.

Abstract  A high yield synthesis of 1-triacontanol was based on the cheap and easily available starting materials 1-octadecanol and 1,12-dodecanediol. The first one was converted to octadecanal using a phase transfer system, whereas the second one after phase transfer bromination and reaction with triphenylphosphine provided 1-hydroxy-12-triphenylphosphonium bromide. Wittig reaction of these two synthons and subsequent hydrogenation furnished the desired product.

Abstract  Penetration of alkane molecules into the adsorbed film of a cationic surfactant gives rise to a surface freezing transition at the alkane-water interface upon cooling. In this paper, we show that surface freezing of hexadecyltrimethylammonium chloride (CTAC) at the tetradecane-water interface stabilizes oil-in-water (OW) emulsions. For concentrations of CTAC near the critical micelle concentration, an OW emulsion coalesced readily above the surface freezing transition whereas the OW emulsion was stable in the surface frozen state. There was a discontinuous change in the stability of the OW emulsion at a temperature very close to the surface phase transition temperature as determined by interfacial tensiometry and ellipsometry on a planar oil-water interface. The mechanical elasticity of the surface frozen layer opposes film drainage and density fluctuations that could lead to rupture and is the most likely cause of the enhanced emulsion stability.

Abstract  Evaluation of the method of preparation and the sequence of metal incorporation onto the catalyst showed that they had profound effects on the catalytic behavior of Ru Sn Al2O3 catalysts used in the selective hydrogenation of oleic acid to 9-octadecen-1-ol. When Ru was loaded first onto the support and then followed by Sn, the catalyst had lower activity but greater ability to preserve the unsaturated bond. On the other hand, when the sequence of loading was reversed, the behavior of the catalyst changed correspondingly, i.e., the catalyst showed higher activity but poorer ability to protect the unsaturated bond. The metal particles incorporated via the sol gel method were finely and evenly distributed on the support. As such, they were more readily shielded by the second metal particles that were subsequently incorporated via the impregnation process. When both metals were loaded via the sol-gel-process, the best result was obtained with superior performance in activity, as well as selectivity in the preservation of double bond.