Rofams - rapeseed oil fatty acid methyl esters oxyethylation products [ROFAME] - a new nonionic class of surfactants
Marian M. Zgoda 1/, Michał J. Nachajski 2/, Michał K. Kołodziejczyk 2/, Jacek Kosno 3/, Marek Lukosek 3/, Sławomira Nowak 4/, Zbigniew Marczyński 5/, Magdalena Piechota-Urbańska 5/, Andrzej Stańczak 5/
1/ Wyższa Szkoła Kosmetyki i Nauk o Zdrowiu w Łodzi
2/ Zakład Technologii Postaci Leku, Katedra Farmacji Stosowanej, Uniwersytet Medyczny w Łodzi
3/ Zakład Procesów Ciśnieniowych, Sieć Badawcza Łukasiewicz - Instytut Ciężkiej Syntezy Organicznej "Blachownia", Kędzierzyn-Koźle
4/ Katedra i Zakład Farmakognozji, Uniwersytet Medyczny w Łodzi
5/ Zakład Farmacji Aptecznej, Katedra Farmacji Stosowanej, Uniwersytet Medyczny w Łodzi
Introduction. Using biodegradable rapeseed oil fatty acid methyl esters [ROFAME], research was undertaken on the production of a new class of nonionic surfactants - Rofams of a low content of polyethylene glycols (PEG) in the product, with the (Al2O3 MgO)n catalyst. Physicochemical properties, and above all, the level of hydrophilic-lipophilic balance (HLB) of their structure can be the basis for the production of drug forms and cosmetics applied to the skin.
Aim. The aim of the research was to produce a homologous series of a new class of surfactants - Rofams with the content of oxyethylene segments nTE=10÷70 and to investigate their structure, surface activity and to estimate viscosity and hydrodynamic values.
Material and methods. A homologous series of Rofams with the content of nTE=10÷70 was studied. The surface tension and viscosity were measured using pharmacopoeial methods and those recommended by Polish Standards, whereas the dispersion of molecular mass in the product was determined using HPLC and GPC chromatography. The content of oxyethylene segments nTE and polyethylene glycols (PEG) in the product was determined by the 1HNMR spectroscopy. The established structure of a new class of surfactants - Rofams enabled the calculation of the solubility parameter δ1/2.
Results. In the homologous series of Rofams with nTE=10÷70, the dispersion of molecular mass was determined as well as the level of hydrophilic-lipophilic balance (HLB) and solubility parameters δ1/2 using independent methods. The surface activity of aqueous solutions of Rofams was measured using the stalagmometric method and the determined cmc (critical micellar concentration) enabled the calculation of the thermodynamic potential of micelle formation. Basic viscosity and hydrodynamic values were also determined and, above all, the degree of hydration of the micelle structure was estimated.
Conclusions. The physicochemical properties of the homologous series of Rofams - biodegradable nonionic surfactants enable their safe use as emulsifiers, solubilizers and transdermal transition promoters in the production of medicinal and cosmetic forms of preparations applied to the skin (creams, micellar liquids, syndets).
Key words: Rofams, viscosity, surface tension, solubility parameter, hydrophilic-lipophilic balance, molecular mass dispersion