Influence of processing conditions in the manufacture of O/W creams: I. Effect on dispersion grade and rheological characteristics.
Two series of O/W creams having the same general formulation were prepared in three different mechanical conditions (F with an hand blender; S with a turbomixer; T with a vacuum turbo emulsor) using two types of surfactants, polyoxyethylene-cetostearyl alcohols and polyglyceryl-3-methylglucose-distearate. By means of microscopic image analysis it was possible to point out the dispersion grade of the oil internal phase increasing with the energy applied under the conditions of manufacture (F < S < T). The level of dispersion influenced significantly on the rheological characteristics of the creams. With polyoxyethylene-cetostearyl alcohols, the viscosity of creams increased as the energy applied in manufacturing increased, with polyglyceryl-3-methylglucose-distearate on the contrary decreased. Moreover, indifferently to the manufacturing conditions, even in the same concentration of surfactant, the creams obtained with the last produced a much greater viscosity. At a parity of manufacturing conditions the differences between the batches of productions were not significant.
Realdon
Nicola
N
Department of Pharmaceutical Sciences, Faculty of Pharmacy, University of Padova, Italy. nicola.realdon@unipd.it
Perin
Francesco
F
Morpurgo
Margherita
M
Ragazzi
Enrico
E
D002498:Centrifugation; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D004345:Drug Industry; D004355:Drug Stability; D004655:Emulsions / Q000737:chemistry*; D005233:Fatty Alcohols / Q000737:chemistry*; D005989:Glycerides / Q000737:chemistry*; D008853:Microscopy; D009821:Oils / Q000032:analysis / Q000737:chemistry; D012212:Rheology / Q000379:methods; D013228:Stearates / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry; D013997:Time Factors; D014783:Viscosity; D014867:Water / Q000737:chemistry
D004655:Emulsions; D005233:Fatty Alcohols; D005989:Glycerides; D009821:Oils; D013228:Stearates; D013501:Surface-Active Agents; C469186:polyglyceryl-3-methylglucose-distearate; D014867:Water