Methods for measuring the skin-cleansing effect of surfactants in comparison with skin roughness and compatibility

Standardization of skin cleansing in vivo: part II. Validation of a newly developed Automated Cleansing Device (ACiD)

“…Regarding contact pressures, Schrader described good detergency by using his skin washing machine which worked with minimal pressures ranging from 6.8 g/cm² to 16 g/cm² . In our model, when using ACiD with the approximately comparable low pressure setting (design B: contact pressure 75 g/3.81 cm² = 19.6 g/cm²), these results could not be reproduced; detergency was inhomogeneous and thus insufficient.…”

“…The in vivo‐ validation of ACiD represents a novelty. So far, none of the published skin cleansing machines was evaluated regarding comparability and reproducibility of the devices, neither intra‐device specific nor inter‐device‐specific . However, this seems pivotal if a standardization and wide implementation is intended.…”

“…Briefly, ACiD produces standardized mechanical influences on three areas on the volar forearm and meets the quality standard DIN EN ISO 13485 for medical devices; contact pressure (g), rotation per minute (rpm), and duration of the exposure can be adjusted. The contact pressure of the washing modules is modifiable between 5 g and 150 g (accuracy ±1.5 g), the rotation speed per minute between 10 and 100 rpm (accuracy ±2 rpm) and the washing time between 1 and 999 s. Furthermore, the apparatus combines rotation with wiping (12 wipes per minute) for creating a homogenous washing result and therefore combines the techniques of Schrader/Rohr , Schrader and Tronnier . It consists of three independent rotating and wiping washing modules and is designed for use on the volar forearm on human subjects.…”

Standardization of skin cleansing in vivo: part I. Development of an Automated Cleansing Device (ACiD)

“…According to Schrader/Rohr Tronnier's hand‐held ‘washing stirring rod’ was characterized by an inherent variation of washing frequencies and contact pressure and thus resulted in non‐reproducible detergency. Therefore, Schrader developed a skin washing machine that wiped (48–80 times per min) with a constant contact pressure of 6.8 g , 14 g , or 16 g .…”

“…In theory, there are already various models and detection methods for assessing cleansing effectiveness of industrial cleaners, but without simultaneously evaluating the skin compatibility: the hand washing test , different devices with ‘stirring rods’ , standardized washing procedures using the skin washing machine by Schrader , machineries without causing mechanical pressure on the skin, like the ‘rotating soap solution’ by Wolf/Friedman and Wolf et al. or the skin cleansing apparatus by Jacobi and procedures that induce pressure without friction, like the manual cleansing by using a paint roller . …”