Determination of area (α) form and volume (β) factors of α-lactose cristal using optic microscopy

Determinación de los Factores de Forma de Área (α) y Volumen (β), de Cristales de α-Lactosa Utilizando Microscopia Óptica

α-lactose crystall were obtained from a 60% (p/p) saturated solution at 90 °C. The solution was air cooled (no seeds) up to 30 °C in a 600 ml solution capacity lab crystallyzer. Measures were taken from separated - washed crystall inmersed in analytic grade ethanol. Four lineal dimension measures of ten crystall images were photographed using an electronic microscope attached to an image analysis system. Data were used to calculate supeficial area (Sa) and crystall volume (Cv) referred to characteristic longitude (Cl) and esphericity (f). α-lactose crystall area form (α) and volume (β) factors were calculated using a non-lineal general model. A regression procedure with Statistic 6.0 specific function was performed. Area form and volume factor values obtained through optic microscopy are in agreement with previous reports, indicating accuracy to determine α-lactose area form and volume factors.

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