Transformation of eutectic emulsion to nanosuspension fabricating with solvent evaporation and ultrasonication technique

Thawatchai Phaechamud,1 Sarun Tuntarawongsa2 1Department of Pharmaceutical Technology, 2Pharmaceutical Intelligence Unit Prachote Plengwittaya, Faculty of Pharmacy, Silpakorn University, Nakhon Pathom, Thailand Abstract: Eutectic solvent can solubilize high amount of some therapeutic compounds. Volatile eutectic solvent is interesting to be used as solvent in the preparation of nanosuspension with emulsion solvent evaporation technique. The mechanism of transformation from the eutectic emulsion to nanosuspension was investigated in this study. The 30% w/w ibuprofen eutectic solution was used as the internal phase, and the external phase is composed of Tween 80 as emulsifier. Ibuprofen nanosuspension was prepared by eutectic emulsion solvent evaporating method followed with ultrasonication. During evaporation process, the ibuprofen concentration in emulsion droplets was increased leading to a drug supersaturation but did not immediately recrystallize because of low glass transition temperature (Tg) of ibuprofen. The contact angle of the internal phase on ibuprofen was apparently lower than that of the external phase at all times of evaporation, indicating that the ibuprofen crystals were preferentially wetted by the internal phase than the external phase. From calculated dewetting value ibuprofen crystallization occurred in the droplet. Crystallization of the drug was initiated with external mechanical force, and the particle size of the drug was larger due to Ostwald ripening. Cavitation force from ultrasonication minimized the ibuprofen crystals to the nanoscale. Particle size and zeta potential of formulated ibuprofen nanosuspension were 330.87±51.49 nm and -31.1±1.6 mV, respectively, and exhibited a fast dissolution. Therefore, the combination of eutectic emulsion solvent evaporation method with ultrasonication was favorable for fabricating an ibuprofen nanosuspension, and the transformation mechanism was attained successfully. Keywords: eutectic, emulsion solvent evaporation, ibuprofen, nanosuspension, ultrasonicatio

Surface Tension and Viscosity of Herbal Massage Oil

Herbal oils have been used for centuries as a traditional medicine. In this study, herbal massage oil was prepared by using crocodile oil (CO) or virgin coconut oil (VCO) as carrier oil. This experiment was conducted to find out the suitable method for preparation of herbal massage oils from CO or VCO. The satisfactory appearance and viscosity of herbal massage oil was received when using 44.9% by weight of crocodile oil as carrier oil. Searching appropriate for herbal massage oil, that exhibited the good characteristic, viscosity, fragrance and hot, was done with various systems. The carrier oils heated with Zingiber montanum (Plai, ZM) (22.45 % w/w) and Curcuma sp. (Wan ma leung, CS) (22.45 % w/w) and then the mixture was mixed with butylated hydroxyl toluene (BHT), menthol, methyl salicylate and camphor were likely to be the appropriate method. The surface tension of the mixture between different herbal oils and carrier oil in the ratio of 1:1 was no significantly difference. The highest viscosity was obtained from the mixture of carrier oil and Curcuma aromatic (Wan nang kum, CA). Oil extracted from herbal with heat treatment could mask the unpleasant odor of CO and VCO but not significantly affected the surface tension and viscosity of carrier oils.</jats:p

Polymeric Eutectic System

The liquid eutectic system comprising 1:1 menthol:camphor was selected to use as solvent due to it was lowest viscosity. Both menthol and camphor used in this eutectic system have been reported for their many pharmaceutical used. Various polymers were tested for their solubility in this eutectic system. Eudragit® EPO showed the highest solubility. Eudragit® EPO was the one of biocompatible polymer which could dissolve in this eutectic system up to 40% w/w with no chemical interaction of each compound. Viscosity of this system showed the exponential curve as a function of polymer concentration but all concentration showed the newtonian rheology. The pH and surface tension were slightly affected by type and amount of polymers. The obtained polymeric eutectic mixture should control the drug release for pharmaceutical applications.</jats:p

Development of Soaps Containing Betel Nut Extract

Areca catechu L. or betel nut tree is one of popular traditional herbal medicines used in Thailand. The betel nut, seed of Areca catachu contains polyphenols, flavonoids and alkaloids that have a potent muscarinic action, which the potential application in Alzheimers disease and antioxidative effect have been mentioned. The anti-aging effects of Areca catechu L. extract on skin has been investigated previously which it could improve the skin hydration, skin elasticity, and wrinkle reduction. The methanolic extract of Areca catechu L. seed gave high antioxidant activity than the other parts of this plant. This study aimed to investigate the factors affecting the physical properties of soap formula containing methanolic Areca catechu L. seed extract. Hardness of opaque soap was not affected by an addition of Areca catechu L. seed extracts but it affected on that of transparent soap. 0.1, 5 %w/w Areca catechu L. seed extracts affected the foaming capacity of opaque soap. In contrast, addition of Areca catechu L. extracts on transparent soap did not affect the foaming capacity. The opaque soap containing 5 %w/w methanolic Areca catechu L. seed extract with 3%, 5%, and 10 %w/v dilution solution exhibited the activity against S. aureus which were not significantly different from that of the soap base.</jats:p

Menthol, Borneol, Camphor and WS-3 Eutectic Mixture

Eutectic system is a mixture or solution which the ingredients solidify or liquefy simultaneously. A eutectic mixture is therefore that unique composition of two (or more) components that has the lower crystallization temperature or melting point. This aim of this study was to prepare and characterize the eutectic systems containing menthol, borneol, camphor and N-Ethyl-5-methyl-2-(1-methylethyl) cyclohexanecarboxamide (WS-3). Menthol is able to form liquid eutectic at room temperature with camphor in the ratio of 8:2, 7:3, 6:4 and 5:5 whereas menthol and borneol in the ratio of 8:2 and 7:3, menthol and WS-3 in the ratio of 6:4 and 1:1. The rheology behavior of all liquid eutectic systems was Newtonian flow which the surface tension was in the range of 28-29 mN/m. From contact angle measurement, all liquid eutectic systems were categorized as high wettability to the glass plate. The suitable liquid eutectic system for further application as liquid carrier for injectable active compounds was 1:1 menthol:camphor because of its lowest viscosity. IR spectra indicated that there was no chemical interaction of these two materials in the selected liquid eutectic mixture.</jats:p

Thermal Analysis of Chitosan-Lactate and Chitosan-Aluminum Monostearate Composite System

Chitosan possess many attractive properties for applying as biomaterials. For some application, biomaterial devices have to be sterilized using high temperature, e.g. stream sterilizing process. However, thermal degradation behavior of chitosan has been reported previously. Many researchers have attempted to improve thermal degradation behavior of chitosan by synthesize chitosan derivatives or blending chitosan with other polymers or additives. However, chitosan derivatives found to be less thermal stability than chitosan itself. On the contrary, adding some lipid additive could improve thermal stability of chitosan. In this study, protecting effect of aluminum monostearate (Alst) on thermal stability of chitosan was investigated employing thermal analysis techniques, e.g. thermogravimetry (TG), differential scanning calorimetry (DSC) and hot-stage microscope. Lactic acid solution (2% w/v) was used as solvent for dissolving chitosan. Chitosan solution, named as chtiosan-lactate (CL) and chitosan solution contained 2.5% w/w Alst (CLAlst) were prepared and fabricated into sponges using freeze drying technique. Degradation temperature of CLAlst system investigated from TG was shifted to the higher temperature comparing that of CL which indicated that Alst could improve thermal stability of chitosan after processed as biomaterial. From DSC result, small endothermic peak was observed around 60-70°C for CLAlst whereas that of CL did not exhibit any peak. Melting behavior of the sponges observed under hot-stage microscope was demonstrated that chitosan was decomposed whereas Alst dispersed in chitosan backbone was gradually melted.</jats:p

Rapidly Dried Antimicrobial Spray for Foot Deodorant

This paper aimed to develop a physiologically activated dried antimicrobial spray for foot deodorant and select the suitable components such as film forming agent, solvent, antimicrobial agent and flavoring agents. The evaporation rates, antimicrobial activity, spray pattern, viscosity and cooling effect were evaluated. The developed formulation exhibited the high evaporating rate, high antimicrobial activity, appropriate spray pattern, slightly viscous solution with cooling effect after spraying onto skin. The developed formulation exhibited the potential application as the rapidly dried antimicrobial spray for foot deodorant.</jats:p

Theophylline extended-release monolithic matrix comprising natural rubber latex as binder

Abstract A major component of polymer in natural rubber latex (NRL) obtained from Hevea brasiliensis consists of poly-cis-1,4-isoprene. Poly-cis-1,4-isoprene exhibited interesting physical properties suitable for possible use as a binder in pharmaceutical solid dosage forms such as monolithic matrix tablet. The aim of this study was to study the feasibility of using NRL as the binder in theophylline anhydrous (THE)-incorporated monolithic matrix tablet in comparison with polyvinyl pyrrolidone K-30 (PVP-30). Physical properties of granules and tablets fabricated with wet granulation and tableting process, in vitro drug release test and release kinetic model were investigated and compared with those prepared using PVP-K30 as a binder. THE-incorporated monolithic matrix tablet was successfully fabricated with wet granulation and tableting process using NRL or PVP-K30 as binder. Granules and tablets of monolithic matrix tablet using NRL as a binder exhibited similar physical properties to those of tablet prepared using PVP-K30 as a binder. In addition, the controlled THE release with diffusion mechanism were presented in both formulations. Surprisingly, the addition of sodium bicarbonate in THE monolithic matrix tablets employing NRL as a binder could also prolong the drug release.</jats:p

Bactericidal activity of methanol extracts of crabapple mangrove tree (Sonneratia caseolaris Linn.) against multi-drug resistant pathogens

The crabapple mangrove tree, Sonneratia caseolaris Linn. (Family: Sonneratiaceae), is one of the foreshore plants found in estuarine and tidal creek areas and mangrove forests. Bark and fruit extracts from this plant have previously been shown to have an anti-oxidative or cytotoxic effect, whereas flower extracts of this plant exhibited an antimicrobial activity against some bacteria. According to the traditional folklore, it is medicinally used as an astringent and antiseptic. Hence, this investigation was carried out on the extract of the leaves, pneumatophore and different parts of the flower or fruit (stamen, calyx, meat of fruit, persistent calyx of fruit and seeds) for antibacterial activity using the broth microdilution method. The antibacterial activity was evaluated against five antibiotic-sensitive species (three Gram-positive and two Gram-negative bacteria) and six drug-resistant species (Gram-positive i.e. Methicillin-resistant Staphylococcus aureus, Enterococcus faecalis, Enterococcus faecium and Gram-negative i.e. Extended-spectrum beta-lactamase-Escherichia coli, multidrug-resistant-Pseudomonas aeruginosa and Acenetobacter baumannii). The methanol extracts from all tested parts of the crabapple mangrove tree exhibited antibacterial activity against both Gram-positive and Gram-negative bacteria, but was mainly a bactericidal against the Gram-negative bacteria, including the multidrug-resistant strains, when compared with only bacteriostatic on the Gram-positive bacteria. Using Soxhlet apparatus, the extracts obtained by sequential extraction with hexane, dichloromethane and ethyl acetate revealed no discernable antibacterial activity and only slightly, if at all, reduced the antibacterial activity of the subsequently obtained methanol extract. Therefore, the active antibacterial compounds of the crabapple mangrove tree should have a rather polar structure