Sensory Evaluation
The skin feeling of SilkyGel and Hyaluronic acid (HA) in different concentration of water solution was test by 20 volunteers. The score range was from 0 to 4: 0 means no smooth feeling, 4 means strong smooth feeling. The result showed that the water solution of 0.1% SilkyGel has sensible smoothing feeling, but HA doesn’t. The degree of smoothing feeling keep pace with concentration, and the score of SilkyGel is better than HA (Figure 1). In high concentration (0.4%), SilkyGel keep its smooth feeling but HA has a conglutinative feeling.
Figure 1. Smooth feeling of SilkyGel and HA
In-vitro studies of moisturizing ability
We compared the moisturizing ability of SilkyGel, γ-PGA (from market), and HA in different relative humidity. In 81% relative humidity, γ-PGA showed the best hygroscopicity and moisture retention, the performance of SilkyGel is worse than γ-PGA but better than HA. In 32% relative humidity, SilkyGel performs the best (Figure 2).
Figure 2. Hygroscopicity and moisture retention in different relative humidity
In-vivo studies
Short-term Test
The study on hydration degree of skin was tested for 15 volunteers in a room with 25℃, RH 45% environment. The concentration of SilkyGel, γ-PGA, and HA were 0.4% in cream. Blank cream was free of active ingredient. Four creams were spread on different areas of volunteer’s arm, and untreated area was as control. The change of degree of hydration of different skin areas in 8 hours was measured by MPA-580 system.
The result was shown in Figure 3.
Figure 3. Percentage change of degree of skin hydration in 8 hours
Long-term Test
The concentration of SilkyGel, γ-PGA, and HA were 0.2% in cream, blank cream was free of active ingredient. Every cream was applied for 10 volunteers for 2 weeks, used twice daily. The degree of hydration, TEWL, and elasticity of face skin were measured using MPA-580 system at 0, 1 and 2 weeks.
The result was shown in Figure 4 to Figure 6.
Figure 4. Percentage improvement in degree of hydration
Figure 5. Percentage reduction in TEWL
Figure 6. Percentage improvement in skin elasticity
Conclusion
SilkyGel performs the best although it doesn’t make a significant difference with HA and γ-PGA in some test items.
Criteria
| Appearance | Off-white solid powser | |
| pH (1% water solution) | 6.0 ~ 8.0 | |
| Total nitrogen content (%) | 3.8 ~ 5.0 (Kjeldahl method) | |
| Loss on drying (%) | ≤ 10 % | |
| Total of bacterium (CFU/g) | ≤ 500 | |
| Hg (ppm) | ≤ 1 | |
| As (as As2O3, ppm) | ≤ 10 | |
| Pb (ppm) | ≤ 40 | |
Storage
Sealed, Guard against damp, room temperature.
Suggested usage
0.2% ~ 2.0%
Recommendation of use
• SilkyGel‘s viscosity is sensitive to high temperature, it should be mixed in recipe below 60℃.
• SilkyGel is sensitive to acid, and it shouldn’t be used in pH below 5.5.
Contact us
www.onlystar.com
Email:
market@onlystar.com
huangzhengmei@onlystar.com
liuyuan_sale@onlystar.com
