Page 24 - A. Aging

[A. Aging-13]

Development of natural polymer microneedle to improve

skin elasticity

Da Som Kim¹˙#, Hye seon Lee¹˙#, Sung-Min An¹, Min Jae Kim¹, So Young Kim¹, Da Hee Kang¹,

Seung Yun Yang¹˙*, Beum-Soo An¹˙*

¹Biomaterials Science, Pusan National University, Miryang 50463, Republic of Korea

Skin elasticity is an important marker of skin aging and overall condition. A reduction of the extracellular matrix is

correlated with a decrease of skin elasticity and an increase of skin fragility. Microscale needle (MN), physically
penetrate the skin without pain and release the drugs within dermis directly. In this study, we evaluate the ability

to improve skin elasticity after application of MN patches with natural polymer. We used MN patches with hyaluronic
acid (HA), swellable HA, gelatin, gelpin (crosslinked gelatin), and polystyrene (PS) as a positive control. The negative

control group applied flat polymer plate for mechanical press. The MN patches applied to dermal skin of male SD
rats three times a week for a month. Skin elasticity was measured using cutometer. The HA and gelatin groups

show more higher skin elasticity than PS group. Then we examined the expression of Col1A1, COL1A2, COL3A1,
elastin in dermal skin of rats. As a result, Col1A1 and COL1A2 expression increased in all groups although COL3A1

and elastin expression increased in only gelatin group. We also investigated the thickness of dermal skin using
hematoxylin & eosin staining and it is increased in all groups. These findings suggest that HA or gelatin MN patches

can help improve elasticity of skin.