title: Hydrating effects of moisturizer active compounds incorporated into hydrogels: in vivo assessment and comparison between devices.
abstract: BACKGROUND
  Water is an important factor on the appearance and function of the skin and, when dehydrated, it becomes rough and flaky. The measurement of stratum corneum hydration is widely employed to verify the moisture effect of topical products.
  
  
  OBJECTIVE
  This study has evaluated in vivo the stratum corneum hydration, by the electrical measurements of skin, after treatment with different moisturizers presented in gel base. MoistureMeter and Corneometer were used as bio-instruments. Urea, the herbal extract (Imperata cylindrical), the NMF components and the carbohydrate derivate compound (xylityglucoside, anhydroxylitol, and xylitol) were used as the active substances.
  
  
  METHODS
  The study protocol was carried out according to the three-factor factorial design. The gels were applied on both forearms of eight female volunteers. However, each volunteer had one untreated skin area as the skin moisture control. The electrical capacitance of the skin was measured by both instruments in different times: after application (0 time), 30, 60, 120, 240 and 360 min.
  
  
  RESULTS
  Gel base, gel containing herbal extract, and gel containing NMF components statistically have equal moisture effect measurements, according to both bio-instruments. However, the values obtained for urea, carbohydrate derivate compound, and untreated skin (control) have statically different results in both devices.
  
  
  CONCLUSIONS
  The gel containing urea and the carbohydrate derivate compound gel have promoted the most intense moisture effect compared with the other formulations. The measurements of hydration between the devices generated different absolute values; however, the statistical analysis has shown similar precision among the measurements.
authors.affiliation: Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Vânia Rodrigues
authors.initials: VR
authors.lastname: Leite e Silva
authors.forename: Marcelo Ariel
authors.initials: MA
authors.lastname: Schulman
authors.forename: Cibeli
authors.initials: C
authors.lastname: Ferelli
authors.forename: Janine Mailho
authors.initials: JM
authors.lastname: Gimenis
authors.forename: Gabriele Wander
authors.initials: GW
authors.lastname: Ruas
authors.forename: André Rolim
authors.initials: AR
authors.lastname: Baby
authors.forename: Maria Valéria Robles
authors.initials: MV
authors.lastname: Velasco
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Taqueda
authors.forename: Telma Mary
authors.initials: TM
authors.lastname: Kaneko
mesh_terms: D000279:Administration, Cutaneous; D000328:Adult; D000704:Analysis of Variance; D001834:Body Water / Q000187:drug effects; D002626:Chemistry, Pharmaceutical; D016001:Confidence Intervals; D025802:Electric Capacitance; D055664:Electrochemical Techniques / Q000379:methods*; D004817:Epidermis / Q000187:drug effects* / Q000378:metabolism; D005260:Female; D005542:Forearm; D005712:Galvanic Skin Response; D006801:Humans; D020100:Hydrogels / Q000378:metabolism / Q000494:pharmacology*; D011336:Probability; D012016:Reference Values; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D012867:Skin / Q000187:drug effects / Q000378:metabolism; D012869:Skin Absorption / Q000187:drug effects* / Q000502:physiology; D055815:Young Adult
chemical_list: D020100:Hydrogels