• Clean Technology
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• v.12 no.1
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• pp.45-51
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• 2006

Colloidal Liquid Aphrons(CLAs) were prepared from different solvents such as nonpolar hydrocarbons, alcohols, and amines. Water-soluble surfactant and oil-soluble surfactant were used in this study. The effect of PVR (phase volume ratio) and concentration of extractant on the stability of CLA was investigated. The stability of CLA was affected by PVR. As PVR was increased, the stability of CLA was decreased.

• Journal of the Korean Chemical Society
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• v.43 no.2
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• pp.172-181
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• 1999

To develop the manufacturing technique for the powder builder of amorphous solid types, the water glass mixed with caustic soda dispersed into the methanol. Thus soluble sodium silicate was made a form of amorphous solid powder. In order to examine characteristics of water soluble sodium silicate $SiO_2/Na_2O$ mol ratio, we investigated solubility, thermogram, SEM, and BET analysis. pH buffering capacity, calcium-ion binding capacity as temperature change, and surfactant loading capacity were examined for characteristics as laundry detergent builder. $SiO_2/Na_2O$ molar ratio of soluble sodium silicate was 1.0, 2.4, 2.8, and zeolite was used in order to investigate basic characteristics of laundry detergent builder. Silicate used with laundry detergent was good for pH buffering capacity and solubility. But calcium-ion binding capacity and surfactant adsorption ability were lower. $SiO_2/Na_2O$ mol ratio became higher, pH buffering capacity and ion exchange ability were lower and surfactant adsorption ability was a little higher.

• Journal of the Korean Applied Science and Technology
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• v.19 no.2
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• pp.79-85
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• 2002

The cutaneous tolerability of detergent formulations can be improved by means of suitable additives. They complex the surfactant molecules lowering the concentration of their free monomeric species. Proteins derivatives used as additives for detergency are usually prepared by partial hydrolysis of plant reserve proteins. The main purpose of the hydrolytic cleavage is to make them water soluble and suitable for liquid products. Water solubility and stability are obtained by means of complexation with surfactants which also increase their actual hydrophobicity, an important parameter affecting cosmetic properties of proteins. Transepidermal water loss (TEWL) and electric capacitance (EC) have been adopted as investigation technigues to evaluate the skin integrity/damage in vitro tests, The performance of native wheat protein / surfactant complexes has been compared with traditional protein hydrolysates as detergent additives. The results show a noticeable reduction of skin irritation in surfactant formulations with addition of native wheat protein.

• Journal of Pharmaceutical Investigation
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• v.40 no.spc
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• pp.97-102
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• 2010

A novel surface-attached solid dispersion is designed to improve the solubility and oral bioavailability of poorly water-soluble drugs without crystalline change. Accordingly, it draws increasing interest because of excellent stability and no pollution for accomplishing enhanced solubility and bioavailability, which have recently been highlighted in connection with a number of higher value-added poorly water-soluble drugs. In addition, excellent stability can be attained when the poorly water-soluble drugs are not dissolved but dispersed in water and provide no crystallinity change. This solid dispersion is given by means of attaching the dissolved carriers such as hydrophilic polymer and surfactant to the surface of dispersed drug particles followed by changing the hydrophobic drug to hydrophilic form. The aim of the present review is to outline the preparation, physicochemical property and bioavailability of novel surface-attached solid dispersion with improved solubility and bioavailability of poorly water-soluble drugs without crystalline change.

• Journal of Pharmaceutical Investigation
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• v.29 no.1
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• pp.37-45
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• 1999

ABSTRACT-A self-microemulsifying drug delivery system (SMEDDS) was developed to enhance the solubility and dissolution rate of poorly water soluble drug, biphenyl dimethyl dicarboxylate, DDB. The system was optimized by evaluating the solubility of DDB and the microemulsion existence range after the preparation of microemulsions with varying compositions of triacetin and surfactant-cosurfactant mixtures (Labrasol as surfactant (S) and the combination of Transcutol, Cremophor RH 40 and Plurol oleique as cosurfactant (CoS)). SMEDDS in this study markedly improved the solubility of DDB in water up to 10 mg/ml and the size of the o/w microemulsion droplets measured by dynamic light scattering showed a narrow monodisperse size distribution with an average diameter less than 50 nm. The microemulsion existing range is increased proportional to the ratio of S/CoS, however, it decreased remarkably as the oil content was more than 20%. In vitro dissolution study of SMEDDS showed a significantly increased dissolution rate of DDB in water (> 12 fold over DDB powder), and SMEDDS also had significantly greater permeability of DDB in Caco-2 cell compared to powders.

• Bulletin of the Korean Chemical Society
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• v.9 no.5
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• pp.317-322
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• 1988

Premicellar precipitation, resolubilization and luminescing behaviors of $RuL_3^{2+}$ (L = bpy, phen, $Me_2bpy$) in aqueous alkylsulfate and sulfonate solutions were studied. Addition of the anionic surfactants to $RuL_3\;^{2+}$ solutions caused initial precipitation which was redissolved by further addition of the surfactants. The apparent solubility products $K_{sp}$'s of the precipitates were evaluated assuming 1:2 salt formation. The values were smaller as the ligand is more hydrophobic and the length of hydrocarbon chain of the surfactant is longer. The $K_{sp}$ values for L = bpy were constant over wide surfactant concentration range. However, those for L = $Me_2bpy$ and also for phen, but to less extent, increased with the surfactant concentration. The resolubilization of 1:2 salts was followed by red-shift of emission band and extensive emission quenching above critical concentration of the surfactants. The critical concentration was lower for more hydrophobic surfactant. For L = $Me_2bpy$, the blue-shifted emission band with enhanced emission intensity was observed in intermediate surfactant concentration region. The high ionic strength of media prevented the precipitate formation, but facilitated the red-shift of the emission bands. The results support that the precipitate is dissolved by accretion of surfactant anions to the salts to form water-soluble surfactant-rich $RuL_3$-surfactant anionic species. These species appeared to aggregate cooperatively to produce large clusters which exhibited the red-shifted emission.

• Korean Membrane Journal
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• v.1 no.1
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• pp.43-49
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• 1999

Separation of soluble oil was investigated during filtration of cutting oil emulsion using various commercial ultrafiltration membranes. The surface properties of membranes used were hydrophilic hydrophobic and modified surfaces by various surfactant pretreatments. Conditions varied include stirring speed transmeembrane pressure membrane type and surfactant type for pretreatment. The results give some indication of mechanisms occurring at the membrane surface. Surfactant pretreatments significantly improved water flux and UF flux of hydrophilic regenerated cellulose(up to 2.4x for YM100) and hydrophobic polysulfone (up to 2.2x for PTHK) membranes depending on surfactant type and operating conditions. The UF flux enhancement was attributed to membrane swelling and reduction of interfacial surface tension between oil droplets and membrane surface. unexpectedly the hydrophilic membranes revealed greater flux enhancement than the hydrophobic membranes. The results also showed a greater improvement in UF flux at lower operating pressure.

• YAKHAK HOEJI
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• v.40 no.3
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• pp.243-250
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• 1996

In order to formulate aqueous multivitamin solutions containing both oil-soluble (A, D, E) and water-soluble vitmains ($B_1,\;B_2,\;B_6,\;B_{12}$, C and niacinamide) in 1ml-dose, the effects of various additives such as cosolvents (propylene glycol, polyethylene glycol, glycerin), a sweetener (sorbitol) and a surfactant (Cremophor$^{\circledR}$ RH40) on the solubility of oil-soluble vitamins in water were evaluated. Cremophor$^{\circledR}$ RH40 showed the excellent capacity on the solubilization of oil-soluble vitamins, and the simultaneous addition of cosolvents and surfactant resulted in synergetic effects on the solubilization of oil-soluble vitamins. The effects of the combination of the cosolvents and sweetener on the stability of multivitamin solutions were also evaluated by determining the amount of vitmain A and $B_1$ remained in the solutions after storing at $40^{\circ}C$ for 9 weeks. The formulation consisting of Cremophor$^{\circledR}$ RH40 15%, PG 20%, and sorbitol 20% resulted in the best stability of vitamin A and $B_1$. The stability of vitamin A and $B_1$ in this formulation was evaluated at 50, 60, and $70^{\circ}C$ up to 40 days. The shelf-lives of vitamin A and $B_1$ in the formulation, calculated using the Arrhenius equation, were 1,521 days and 475 days at $20^{\circ}C$, respectively.

• Journal of the Korean Applied Science and Technology
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• v.25 no.1
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• pp.23-31
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• 2008

In general, anionic and cationic surfactants are incompatible because their mixtures form insoluble complexes. There are, however, some complexes that are soluble and behave like regular surfactants, specifically like nonionic surfactants, thus named pseudo-nonionic surfactant complexes. Pseudo-nonionic complexes are more effective and efficient than their ionic surfactant components as shown by their equilibrium and dynamic surface tensions and interfacial tensions. They pack at the interface more than their ionic components. Since, pseudo-nonionic complexes show their own characteristics, they can be treated as separate classes of surfactants distinct from ionic and nonionic surfactants. Novel cationic surfactant was synthesized, having the polyhydroxyl group at the head group. We found that aqueous mixtures of our cationic surfactant and usual anionic surfactant(SDS) could form homogeneous solutions even at high concentration. The properties of mixed surfactant solutions were measured. Foam stability, CMC(critical micelle concentration), water hardness tolerance and thickening effect were tested. The foam stability of mixed surfactants was very good and various synergy effects were observed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.4
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• pp.271-279
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• 2013

Water-soluble collagen (30 wt%) was entrapped within oil phase of lipstick using reversed micelle method to improve the moisture capacity of the lipstick. Reversed micelles containing collagen were prepared using caprylic/capric triglyceride as external phase and polyoxyethylene (10) octylphenyl ether (Triton X-100) and 1-dodecanol as surfactant and co-surfactant, respectively. The formation of reversed micelle encapsulating collagen was confirmed by measuring electric conductivity and UV-vis spectrum using methylene blue (MB). The stability and moisture capacity of the lipstick containing 20 wt% collagen encapsulated reversed micelles were observed by measuring rheology property, moisture content and amino acid content. The molecular ratio (W, water-pool) of water to surfactant (Triton X-100) in the most stable reversed micelle was ${\leq}$ 10. The hardness of the lipstick had no difference with that of the lipstick without reversed micelle, and the moisture content was increased to 59% and the amino acid content was 92.7%.