Isostearic Acid Research Articles

Exploring hydrophobic surface modifications in silica and alumina nanomaterials✰

Superhydrophobic materials have attracted significant attention in various applications including leather manufacturing, water-resistant textiles, self-cleaning surfaces, anti-icing coatings, etc... In the present work, we elucidated the functionalization of silica nanoparticles using isostearic acid, a cheap, non-toxic and highly branched molecule, substituting the conventional toxic fluorinated molecules, in comparison with the alumina counterpart and commercial hydrophobic materials. In this respect, the performance of isostearic acid is compared to the commercially used hexamethyldisilazane, a rigid and bulky moiety of high toxicity and environmental persistence. The functionalized surfaces were characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, N2 physisorption, field emission scanning electron microscopy, and thermogravimetric analysis. Microgravimetric and microcalorimetric measurements were also used to describe the surface interaction with water, while the water-repellency at the macroscopic level was monitored through contact angle measurements. Both silica surfaces functionalized with isostearic acid and hexamethyldisilazane show a collective superhydrophobic behavior, but the flexibility of the isostearic acid chains, bonded in low surface density (0.7 units per nm2) through alkyl chains, allow for diffusion of water vapor at the molecular level, while this is not observed in the hexamethyldisilazane case due to the smaller molecular size of the rigid moiety, coupled to a higher surface density (3.5 units per nm2). The results revealed that a material does not necessarily expose micro-nano hierarchical structures to reach an ultimate waterproof capability with a contact angle higher than 150°.

Friction of Methyl-Branched Fatty Acid Layers at Low and High Sliding Speeds.

The friction of methyl-branched fatty acids was studied with a surface forces apparatus (SFA) with attachments for low-speed (μm/s) and high-speed (cm/s) sliding. The systems studied were isooleic acid, a mixture of unsaturated C-18 isomers with one methyl group located along the chain, and isostearic acid, which consisted of saturated C-18 isomers with one methyl branch. The methyl group was expected to disrupt the close packing of the molecules in the pure substance and when adsorbed on a surface. The friction forces and friction coefficients were compared with results for stearic and oleic acid. Isostearic acid showed low friction at low speeds. At high speeds, a peak was found in the friction coefficient of both isostearic and isooleic acid layers, whereas a gradual increase in friction coefficient with speed was seen for oleic acid, suggesting different relaxation times of the structures formed on the surfaces.

A Novel Riboflavin Formulation for Corneal Delivery Without Damaging Epithelial Cells.

This study aimed to evaluate the trans-epithelial permeability enhancement and cell damage caused by a novel riboflavin composition for corneal delivery. We developed a trans-epithelial formulation of riboflavin for corneal delivery using 1,2-dioleoyl-3-dimethylammonium-propane (DODAP) and isostearic acid (ISA). The permeation enhancement was evaluated using an in vitro corneal epithelial cell culture system by measuring the amount of transferred riboflavin with high-performance liquid chromatography. Riboflavin permeation of MedioCROSS TE, a commercially available riboflavin formulation containing benzalkonium chloride, was also evaluated and compared to that of the DODAP/ISA formulation by changing the riboflavin concentration. The trans-epithelial electrical resistance (TEER) was measured after exposure to the samples in an in vitro corneal epithelial cell culture system to assess cytotoxicity. The DODAP/ISA formulation demonstrated greater permeation when used together than when each component was used individually. The permeation enhancement effect of the DODAP/ISA formulation was almost the same as that of MedioCROSS TE. However, when a 10-fold higher riboflavin concentration was used in the DODAP/ISA formulation, the permeation enhancement effect surpassed that of MedioCROSS TE. After 24hours of exposure, the TEER of the DODAP/ISA formulation was higher than that of MedioCROSS TE, indicating that the DODAP/ISA formulation was less cytotoxic than MedioCROSS TE. This study indicated that the DODAP/ISA formulation could serve as a less cytotoxic alternative to MedioCROSS TE. Further studies are required to determine the clinical efficacy and safety of the DODAP/ISA formulation in vivo. This study may provide alternative procedures for corneal collagen crosslinking with less of a cytotoxic effect on corneal epithelial cells.

Synthesized biolubricants from naturally derived oleic acid: Oxidative stability and cold flow performance

Bio-lubricants are receiving increased interest due to their environmental advantages over petroleum-based analogues. This research demonstrates the evaluation and comparison of thermal and kinetic properties of bio-lubricants synthesized from naturally derived fatty acids. The oxidative stability of the vegetable oil-based bio-lubricants affects their storage stability and reusability. Five different types of bio-lubricants were previously synthesized from oleic acid, iso-oleic acid, and iso-stearic acid. Thermogravimetric analysis was conducted in the presence of air and nitrogen. Comparative studies of the kinetic parameters under thermal decomposition of each synthesized product show that these bio-lubricants are thermally stable. The calculated activation energy showed that trimethylolpropane iso-oleic acid triester (TMP-IOA) was thermally stable with an average activation energy Ea = 188.4 kJ/mol in an inert environment (Under N2). In the oxidative environment (under air), trimethylolpropane iso-stearic acid triester (TMP-ISA) was found as the most stable bio-lubricant with an Ea= 109.8 kJ/mol. The glyceride-iso-oleic acid triester (GLY-IOA) showed a high range frequency factor indicating complex behavior in an air environment. Among these lubricants, the GLY-IOA exhibited superior cold flow properties as measured using cryogenic differential scanning calorimetry. Overall, these comparative studies confirm that the lubricant-based oils produced using saturated or monounsaturated fatty acid provide a good combination of thermal and oxidative stability along with cold flow properties.

Chemistry of Dimer Acid Production from Fatty Acids and the Structure-Property Relationships of Polyamides Made from These Dimer Acids.

While there is abundant literature on using a wide range of biomaterials to make polymers for various adhesive applications, most researchers have generally overlooked developing new adhesives from commercially available bio-based dimerized fatty acids. Some of the literature on the chemistry taking place during the clay-catalyzed dimerization of unsaturated fatty acids is generally misleading in that the mechanisms are not consistent with the structures of these dimers and a by-product isostearic acid. A selective acid-catalyzed interlayer model is much more logical than the widely accepted model of clay-catalyzed Diels-Alder reactions. The resulting dimers have a variety of linkages limiting large crystal formation either as oligomeric amides or polyamides. These highly aliphatic fatty acid dimers are used to make a wide range of hot melt polyamide adhesives. The specific structures and amounts of the diacids and diamines and their relative ratios have a big effect on the bio-based polyamide mechanical properties, but analysis of the structure-property relationships has seldom been attempted, since the data are mainly in the patent literature. The diacids derived from plant oils are valuable for making polyamides because of their very high bio-based content and highly tunable properties.

Clarification of the effects of adsorption films of ester-blended oil on friction by in situ reflectance spectroscopy

In recent years, the demand for friction reduction in oil lubrication systems has become increasingly important due to the need to improve fuel economy and achieve carbon neutrality. Ester-based lubricants are known to show low friction and environmentally friendly, and they have high viscosity indexes. In the present paper, first, in situ reflectance spectroscopy was used to clarify the behavior of the oil-film thickness increase during sliding. The results showed that as the number of ester bonds increased from 1 to 4, the ester oil film thickened and the friction coefficient decreased from 0.10 to 0.06. In addition, oleic-acid-type lubricants were found to have superior ability to form a thicker oil film than the isostearic acid type.

Methanolic extract of Kigelia africana and wound healing: an in vitro study.

Kigelia africana (Lam.) Benth. (Bignoniaceae) syn. Kigelia pinnata (Jacq. DC) is a tropical plant that is native to tropical Africa. The aim of this study was to determine if a methanolic extract prepared from Kigelia africana (KAE) can promote wound healing in treated human normal epidermal keratinocyte (HaCaT) cells and human normal foreskin fibroblast cell line (BJ) cells compared with untreated cells. Experimental steps included: the methanolic extraction of the leaf and fruit of the Kigelia africana plant; the preparation of HaCaT and BJ cell lines; cell culture with a stable tetrazolium salt-based proliferation assay; and the evaluation of the wound healing effect of KAE (2μg/ml) in BJ and HaCaT cells. The phytochemical contents of KAE were determined using liquid chromatography quadrupole time-of-flight mass spectrometry. The following molecules were identified as being present in the KAE, among others: cholesterol sulfate; lignoceric acid; embelin; isostearic acid; linoleic acid; dioctyl phthalate; arg-pro-thr; 15-methyl-15(S)-PGE1; sucrose; benzododecinium (Ajatin); and 9-Octadecenamide (oleamide). KAE effected faster wound healing in treated cells compared with untreated cells for both cell lines. HaCaT cells that had been mechanically injured and treated with KAE healed completely in 48 hours compared with 72 hours for untreated HaCaT cells. Treated BJ cells healed completely in 72 hours compared with 96 hours for untreated BJ cells. Concentrations of KAE up to 300μg/ml had a very low cytotoxic effect on treated BJ and HaCaT cells. The experimental data in this study support the potential of KAE-based wound healing treatment to accelerate wound healing.

Isostearic acid is an active component of imiquimod formulations used to induce psoriaform disease models.

Topical imiquimod based creams are indicated as immune stimulants for papillomas and various skin neoplasms. Imiquimod is considered a TLR7 ligand. These creams are also used in research to induce skin inflammation in mice as a model for psoriasis. We observed that this inflammatory response was not strictly imiquimod dependent and we set out to establish which components drive the proinflammatory effects. To this end, we examined the induction response in a BALB/cJRj mouse model, in which 50mg of cream is applied to 2 cm2 of skin (125mg/kg imiquimod-5% W/V, and/or 625mg/kg isostearic acid-25% W/V). Comparing cream formulations containing isostearic acid, imiquimod and the combination, we observed that isostearic acid causes skin inflammation within 2days, whereas imiquimod requires up to 5days for initial signs. Isostearic acid activated an inflammasome response, stimulated release of proinflammatory cytokines and upregulated the IL-23/17 axis. Animals treated with isostearic acid had enlarged livers (+ 40% weight), which was not observed with imiquimod alone. Imiquimod was readily metabolized and cleared from plasma and liver, but was maintained at high levels in the skin throughout the body (200mM at area of application; 200µM in untreated skin). Imiquimod application was associated with splenomegaly, cytokine induction/release and initial body weight loss over 3days. Despite high imiquimod skin levels throughout the animal, inflammation was only apparent in the treated areas and was less severe than in isostearic acid groups. As the concentrations in these areas are well above the 10µM required for TLR7 responses in vitro, there is an implication that skin inflammation following imiquimod is due to effects other than TLR7 agonism (e.g., adenosine receptor agonism). In brain, isostearic caused no major changes in cytokine expression while imiquimod alone sightly stimulated expression of IL-1β and CCL9. However, the combination of both caused brain induction of CCL3, -9, CXCL10, -13, IL-1β and TNFα. The implication of these data is that isostearic acid facilitates the entry of imiquimod or peripherally secreted cytokines into the brain. Our data suggest that psoriaform skin responses in mice are more driven by isostearic acid, than generally reported and that the dose and route used in the model, leads to profound systemic effects, which may complicate the interpretation of drug effects in this model.

Selective extraction equilibria of Sc(III), Y(III), Fe(III) and Al(III) from acidic media with toluene mixture of deep eutectic solvent (DES) composed of TOPO and isostearic acid.

A deep eutectic solvent (DES) composed of isostearic acid and TOPO was newly found out and investigated for selective recovery of scandium. The four elements used in this study are scandium, iron, yttrium, and aluminum. It was difficult to separate the four elements owing to the overlap of extraction behavior when isostearic acid or TOPO alone in toluene was used, respectively. However, scandium was able to be selectively extracted from other metals using DES prepared by 1:1mol ratio of isostearic acid and TOPO without toluene. In DES consisting of isostearic acid and TOPO, synergistic and blocking effects with three extractants acted on the extraction selectivity for scandium. Both effects are proved also from the fact that scandium was easily stripped with diluted acidic solutions such as 2M HCl and H2SO4. Thus, DES extracted selectively scandium and back-extraction was easily achieved. In order to elucidate these phenomena above, the extraction equilibria of Sc(III) using DES dissolved in toluene was investigated in detail. The extraction mechanism of scandium by DES in toluene indicates that the extracted chemical species vary with pH, and that trivalent scandium is extracted by forming stable metal complexes with DESs consisting of five molecules of isostearic acid and five molecules of TOPO.

Separation and Recovery of Sc(III) and Y(III) from Aqueous Acidic Media with <i>N</i>-Lauroylsarcosine

In this study, the selective extraction and mutual separation of Sc(III) and Y(III) from Ni(II), Co(II) and Mn(II) in acidic media were performed with N-lauroylsarcosine (NLS) in toluene. The experimental results were quantitatively analyzed using the conventional slope analysis method. This method reasonably elucidated reasonably the extraction equilibrium formulation of these metals with LNS. Isostearic acid with only a carboxylic acid group in the molecule extracted Sc(III) and Y(III) in a higher pH region compared with that with LNS having amide and carboxylic acid moieties. Therefore, we found that the amide group included in the molecule structure of NLS plays an important role to extract these metals. Mutual separation of Sc(III) and Y(III) was carried out by a one-step extraction using NLS from Ni(II), Co(II) and Mn(II) in acidic media. Sc(III) is more strongly extracted than Y(III) with NLS, and the separation factor of the metals is quite high at 4.68×103. Furthermore, the stripping of Sc(III) and Y(III) extracted into the organic phase was achieved using appropriate concentrations of various acids.

Viscosity of Nanoconfined Branched-Chain Fatty Acids Studied by Resonance Shear Measurements.

Lubricant performance can be improved using additives such as organic friction modifiers (OFMs) and is influenced by their conformation and properties in the space confined between the substrate surfaces, rendering the detailed property analysis of confined OFMs and lubricants a matter of high practical significance. To date, studies on fatty acids as confined OFMs have mainly focused on linear- and unsaturated-chain molecules, leaving branched-chain structures underexplored. To bridge this gap, we used resonance shear measurements in this study to probe the viscosity of two branched-chain C18 fatty acids (isostearic acid T and isostearic acid) confined between mica surfaces at different applied normal loads (L) and surface separation distances (D). The viscosity parameter (bs) of both acids significantly increased at D < ∼4 nm because of structuring and was lower for isostearic acid than that for isostearic acid T at L > ∼0.6 mN. This reversal of bulk viscosity order under nanoconfinement was ascribed to the ability of the bulky methyl-substituted side chain of isostearic acid to prevent ordering in the nanospace between the mica surfaces and thus preserve fluidlike properties. The obtained results provide fundamental insights into the lubricity of branched-chain fatty acids and are expected to promote the development of novel high-performance OFMs.

Low Temperature Affects Fatty Acids Profiling and Key Synthesis Genes Expression Patterns in Zanthoxylum bungeanum Maxim.

Zanthoxylum bungeanum is one of the most important medicinal and edible homologous plants because of its potential health benefits and unique flavors. The chemical components in compositions and contents vary with plant genotype variations and various environmental stress conditions. Fatty acids participate in various important metabolic pathways in organisms to resist biotic and abiotic stresses. To determine the variations in metabolic profiling and genotypes, the fatty acid profiling and key differential genes under low temperature stress in two Z. bungeanum varieties, cold-tolerant (FG) and sensitive (FX), were investigated. Twelve main fatty acids were found in two Z. bungeanum varieties under cold stress. Results showed that the contents of total fatty acids and unsaturated fatty acids in FG were higher than those in FX, which made FG more resistant to low temperature. Based on the result of orthogonal partial least squares discriminant analysis, palmitic acid, isostearic acid, linolenic acid and eicosenoic acid were the important differential fatty acids in FG under cold stress, while isomyristic acid, palmitic acid, isostearic acid, stearic acid, oleic acid, linolenic acid and eicosenoic acid were the important differential fatty acids in FX. Furthermore, fatty acid synthesis pathway genes fatty acyl-ACP thioesterase A (FATA), Delta (8)-fatty-acid desaturase 2 (SLD2), protein ECERIFERUM 3 (CER3), fatty acid desaturase 3 (FAD3) and fatty acid desaturase 5 (FAD5) played key roles in FG, and SLD2, FAD5, 3-oxoacyl-[acyl-carrier-protein] synthase I (KAS I), fatty acyl-ACP thioesterase B (FATB) and acetyl-CoA carboxylase (ACC) were the key genes responding to low temperature in FX. The variation and strategies of fatty acids in two varieties of Z. bungeanum were revealed at the metabolic and molecular level. This work provides a reference for the study of chemical components in plant stress resistance.

Isostearyl Mixed Anhydrides for the Preparation of N-Methylated Peptides Using C-Terminally Unprotected N-Methylamino Acids.

Sustainable and efficient manufacturing methods for N-methylated peptides remain underexplored despite growing interest in therapeutic N-methylated peptides within the pharmaceutical industry. A methodology for the coupling of C-terminally unprotected N-methylamino acids mediated by an isostearic acid halide (ISTAX) and silylating reagent has been developed. This approach allows for the coupling of a wide variety of amino acids and peptides in high yields under mild conditions without the need for a C-terminal deprotection step in the process of C-terminal elongation. These advantages make this a useful synthetic method for the production of peptide therapeutics and diagnostics containing N-methylamino acids.

Synthesis of Isostearic Acid/Dimer Fatty Acid-Based Polyesteramide Polyol for the Development of Green Polyurethane Coatings

Bio-based polyurethane (PU) coatings were prepared from novel branched isostearic acid (ISA) and long chains dimer fatty acid. Fatty amide was synthesized by the amidation of ISA with diethanolamine and the required hydroxyl functionality was developed via condensation polymerization with dimer fatty acid to produce polyesteramide polyol. The structure of the synthesized ISA based fatty amide (ISAFA) and polyesteramide polyol (ISAPEP) were identified using Fourier-transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1HNMR). The number average molecular weight of prepared polyesteramide polyol was assessed by gel permeation chromatography (GPC), while the rheological behavior was examined by the rheometer. Polyurethane metal coatings were developed from polyesteramide polyol, which crosslinks with hexamethylene diisocyanate (PU-H) and toluene diisocyanate (PU-T) and studied the influence of isocyanate structure on final PU coatings. A comparison in the crosslinks density of PU films was investigated by the gel content method. Differential scanning calorimetry (DSC) and thermo gravimetric analysis (TGA) were performed to evaluate the glass transition temperature (Tg) and thermal stability of the PU coatings. The surface roughness of prepared PU coatings was examined by Atomic force microscopy (AFM). The PU coated metal panels and films were examined for swelling resistance, hydrophobicity, mechanical, and coating properties. Results confirmed that bio-based long chain fatty acids provided hydrophobicity, flexibility and impact resistance to final PU coatings. It also noted that PU-T coating resulted in increasing thermal, mechanical, and coating properties compared to PU-H coating and this resulted from the structure of TDI, which contribute to higher crosslink density (i.e. presence of aromatic ring).

Intradermal Delivery of an Immunomodulator for Basal Cell Carcinoma; Expanding the Mechanistic Insight into Solid Microneedle-Enhanced Delivery of Hydrophobic Molecules.

Basal cell carcinoma (BCC) is the most common cutaneous malignancy in humans. One of the most efficacious drugs used in the management of BCC is the immunomodulator, imiquimod. However, imiquimod has physiochemical properties that limit its permeation to reach deeper, nodular tumor lesions. The use of microneedles may overcome such limitations and promote intradermal drug delivery. The current work evaluates the effectiveness of using an oscillating microneedle device Dermapen either as a pre- or post-treatment with 5% w/w imiquimod cream application to deliver the drug into the dermis. The effectiveness of microneedles to enhance the permeation of imiquimod was evaluated ex vivo using a Franz cell setup. After a 24-h permeation experiment, sequential tape strips and vertical cross-sections of the porcine skin were collected and analyzed using time-of-flight secondary ion mass spectrometry (ToF-SIMS). In addition, respective Franz cell components were analyzed using high-performance liquid chromatography (HPLC). Analysis of porcine skin cross-sections demonstrated limited dermal permeation of 5% w/w imiquimod cream. Similarly, limited dermal permeation was also seen when 5% w/w imiquimod cream was applied to the skin that was pretreated with the Dermapen, this is known as poke-and-patch. In contrast, when the formulation was applied first to the skin prior to Dermapen application, this is known as patch-and-poke, we observed a significant increase in intradermal permeation of imiquimod. Such enhancement occurs immediately upon microneedle application, generating an intradermal depot that persists for up to 24 h. Intradermal colocalization of isostearic acid, an excipient in the cream, with imiquimod within microneedle channels was also demonstrated. However, such enhancement in intradermal delivery of imiquimod was not observed when the patch-and-poke strategy was used with a non-oscillating microneedle applicator, the Dermastamp. The current work highlights that using the patch-and-poke approach with an oscillating microneedle pen may be a viable approach to improve the current treatment in BCC patients who would prefer a less invasive intervention relative to surgery.

Electroanalysis Applied to Compatibility and Stability Assays of Drugs: Carvedilol Study Case.

Carvedilol (CRV) is a non-selective blocker of α and β adrenergic receptors, which has been extensively used for the treatment of hypertension and congestive heart failure. Owing to its poor biopharmaceutical properties, CRV has been incorporated into different types of drug delivery systems and this necessitates the importance of investigating their compatibility and stability. In this sense, we have investigated the applicability of several electroanalytical tools to assess CRV compatibility with lipid excipients. Voltammetric and electrochemical impedance spectroscopy techniques were used to evaluate the redox behavior of CRV and lipid excipients. Results showed that Plurol® isostearic, liquid excipient, and stearic acid presented the greatest anode peak potential variation, and these were considered suitable excipients for CRV formulation. CRV showed the highest stability at room temperature and at 50 °C when mixed with stearic acid (7% w/w). The results also provided evidence that electrochemical methods might be feasible to complement standard stability/compatibility studies related to redox reactions.

Life Cycle Environmental and Cost Implications of Isostearic Acid Production for Pharmaceutical and Personal Care Products

Like many specialty chemicals used in pharmaceutical, personal care, and cosmetic products, few life cycle inventory data are available to describe the synthesis of isostearic acids (IAs). We investigate the cradle-to-gate life cycle environmental and economic performances of IA production from soybean oil and tall oil, both renewable resources, using chemical process simulation models that integrated experimental measurement and data from patent literature. Multiple life cycle impact assessment metrics were estimated where the difference in the climate change impact was most significant for the soybean oil process (1.9–3.8 kg of CO2 equivalent/kg of IA) compared to the tall oil process (1–1.5 kg of CO2 equivalent/kg of IA); however, results for both are low on a life cycle basis compared to synthetic lubricants. Considering the value added from coproducts, the unit production cost for the soybean oil pathway was lower than that of tall oil but its profit and return on investment were also lower. Despite these differences, soybean oil remains a promising feedstock for expanding “green” IA production. Examining hot spots along the soybean oil to IA life cycle, we identify strategies for environmental and economic improvements at the product conversion and recovery stages. We discuss the challenges of predicting the environmental performance of specialty chemicals and new conversion processes and conclude that detailed process modeling like that performed herein is in many cases necessary for capturing environmental trade-offs.

DEVELOPMENT AND CHARACTERIZATION OF TRANSDERMAL DELIVERY SYSTEM OF DOXAZOSIN MESYLATE

Objective: The study involved development of transdermal delivery system (TDDS) of doxazosinmesylate (doxa) to achieve effective systemic delivery of the drug.Methods: TDDS of doxa was prepared using hydroxypropyl methyl cellulose (HPMC) K100LV and polyvinyl pyrrolidone (PVP) K30 in 3:1 ratio solvent casting method. The formulation was evaluated for folding endurance, moisture uptake, pH, drug content and in vitro permeation. Various permeation enhancers were incorporated at 5% w/w concentration into the patch formulationto study their impact on the drug permeation. The TDDS made with Transcutol® as an enhancer was subjected to accelerated stability studies and in vivo skin irritation studies.Results: The developed TDDS showed folding endurance of 170, moisture uptakeof 15.7%, pH of 6.3, and drug content of 99±1.1% and 66% in vitro permeation of doxa over 24h. The effect of various enhancers expressed in terms of average flux can be summarized as Transcutol® (10.6±2.1 µg/cm2h)&gt;dimethyl sulfoxide(10.17±1.2 µg/cm2h)&gt;benzyl alcohol (9.55±1.3 µg/cm2h)&gt;no enhancer (8.86±1.1 µg/cm2h)&gt;dimethyl isosorbide (8.21±1.5 µg/cm2h)&gt;Isostearic acid (7.82±1.4 µg/cm2h)&gt;propylene carbonate (7.67±1.4 µg/cm2h)&gt;oleic acid (7.12 µg±0.8/cm2h). The formulation was found to be stable during the accelerated stability studies. In vivo studies indicated absence of skin irritation effect the TDDS containing Transcutol®.Conclusion: TDDS of doxa comprising HPMC K100LV and PVPK30 in the ratio of 3:1 and 5% Transcutol® could serve as a potential TDDS in the treatment of benign prostatic hyperplasia (BPH) and hypertension.

Development of Magnesium Oxide–Zeolite Catalysts for Isomerization of Fatty Acids

Three zeolites were treated with magnesium nitrate hexahydrate (Mg(NO3)2⋅6H2O) salt to generate active magnesium oxide (MgO)–zeolite catalysts for the isomerization of oleic acid to give the iso-oleic acid (precursor of isostearic acid). Isostearic acid is a crucial component used in the formulation of bio-lubricants including cosmetic and personal care products. The treatment step is intended to poison (or neutralize) the external acid sites of the zeolites, thus inhibiting the formation of by-products (i.e., dimer fatty acids). The acid sites, crystallinity, thermal property, morphology and elemental composition of the zeolites before and after treatments were investigated by scanning electron microscopy, fourier-transform spectroscopy, thermogravimetric analysis, and x-ray powder diffraction. In addition, the effect of a calcination step after treatment was examined to determine if this step was necessary to obtain an active and stable catalyst. As expected, the higher the concentration of MgO on the zeolites, the less dimer was detected in the isomerization products, while the conversion of oleic acid and selectivity of iso-oleic acid remained at a relatively high level. This is promising because the MgO has deprotonated the external acids of the zeolites to generate a high purity isostearic acid that is potentially suitable for personal care products.

Global isostearic acid market will reach $920 M by 2025

Global isostearic acid market will reach $920 M by 2025