The moisture content measurement of human skin is a significant way to assess skin conditions and diagnose diseases that influence skin function.The necessity of evaluating the efficacy of a cosmetic product makes it ...The moisture content measurement of human skin is a significant way to assess skin conditions and diagnose diseases that influence skin function.The necessity of evaluating the efficacy of a cosmetic product makes it important to improve the accuracy and reproducibility of the measurement.A pair of interdigitated gold electrodes was fabricated on the printed circuit board (PCB) substrate and utilized directly in contact with the measured skin.A square-wave voltage at a single frequency was applied to the electrodes and the corresponding response current was measured to get the equivalent impedance of human skin.Since it's easy to generate and control a square-wave signal by digital electric circuits,this method is suitable to be used in the portable application.The experimental results indicate that good repeatability and satisfied accuracy can be obtained by this method.展开更多
[Objectives] The research aimed to optimize extraction process of fucoidan from Sargassum fusiforme( FSF) and study its moisturizing performance. [Methods]Extracting condition of FSF by cellulase hydrolysis-ultrasonic...[Objectives] The research aimed to optimize extraction process of fucoidan from Sargassum fusiforme( FSF) and study its moisturizing performance. [Methods]Extracting condition of FSF by cellulase hydrolysis-ultrasonic assisted extraction method was optimized. The influences of solvent p H,enzyme dosage,extraction temperature,cellulose hydrolysis time,ultrasonication time,and the ratio of material to liquid on FSF were investigated by single factor and orthogonal experiments. [Results] The optimum extraction conditions were as followings:p H,4. 5; enzyme dosage,1%; extraction temperature,40℃; cellulose hydrolysis time,2 h; ultrasonic time,15 min; and the ratio of material to liquid,1∶ 10( g∶ m L). Under the optimal condition,the extraction yield of FSF was 8. 50%,RSD = 2. 74%. The short-time hygroscopicity( within 8 h) of crude extract of fucoidan from S. fusiforme( CEFSF) was better than glycerin,butanediol,and sodium alginate,and the moisture retention capacity of 1% CEFSF aqueous solution was better than 1% butanediol or 1% sodium alginate,and was equal to 5% glycerin under relative humidity of 43% and 81%. The determination results of skin moisture content and transepidermal water loss rate( TEWL)showed that: 5% CEFSF solution had good moisturizing effect. [Conclusions]The research could provide certain reference for deep development of S. fusiforme.展开更多
文摘The moisture content measurement of human skin is a significant way to assess skin conditions and diagnose diseases that influence skin function.The necessity of evaluating the efficacy of a cosmetic product makes it important to improve the accuracy and reproducibility of the measurement.A pair of interdigitated gold electrodes was fabricated on the printed circuit board (PCB) substrate and utilized directly in contact with the measured skin.A square-wave voltage at a single frequency was applied to the electrodes and the corresponding response current was measured to get the equivalent impedance of human skin.Since it's easy to generate and control a square-wave signal by digital electric circuits,this method is suitable to be used in the portable application.The experimental results indicate that good repeatability and satisfied accuracy can be obtained by this method.
文摘[Objectives] The research aimed to optimize extraction process of fucoidan from Sargassum fusiforme( FSF) and study its moisturizing performance. [Methods]Extracting condition of FSF by cellulase hydrolysis-ultrasonic assisted extraction method was optimized. The influences of solvent p H,enzyme dosage,extraction temperature,cellulose hydrolysis time,ultrasonication time,and the ratio of material to liquid on FSF were investigated by single factor and orthogonal experiments. [Results] The optimum extraction conditions were as followings:p H,4. 5; enzyme dosage,1%; extraction temperature,40℃; cellulose hydrolysis time,2 h; ultrasonic time,15 min; and the ratio of material to liquid,1∶ 10( g∶ m L). Under the optimal condition,the extraction yield of FSF was 8. 50%,RSD = 2. 74%. The short-time hygroscopicity( within 8 h) of crude extract of fucoidan from S. fusiforme( CEFSF) was better than glycerin,butanediol,and sodium alginate,and the moisture retention capacity of 1% CEFSF aqueous solution was better than 1% butanediol or 1% sodium alginate,and was equal to 5% glycerin under relative humidity of 43% and 81%. The determination results of skin moisture content and transepidermal water loss rate( TEWL)showed that: 5% CEFSF solution had good moisturizing effect. [Conclusions]The research could provide certain reference for deep development of S. fusiforme.
