Limits...
A patchless dissolving microneedle delivery system enabling rapid and efficient transdermal drug delivery.

Lahiji SF, Dangol M, Jung H - Sci Rep (2015)

Bottom Line: Dissolving microneedles (DMNs) are polymeric, microscopic needles that deliver encapsulated drugs in a minimally invasive manner.However, due to wide variations in skin elasticity and the amount of hair on the skin, the arrays fabricated on the patch are often not completely inserted and large amount of loaded materials are not delivered.Here, we report "Microlancer", a novel micropillar based system by which patients can self-administer DMNs and which would also be capable of achieving 97 ± 2% delivery efficiency of the loaded drugs regardless of skin type or the amount of hair on the skin in less than a second.

View Article: PubMed Central - PubMed

Affiliation: Department of Biotechnology, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-749, Korea.

ABSTRACT
Dissolving microneedles (DMNs) are polymeric, microscopic needles that deliver encapsulated drugs in a minimally invasive manner. Currently, DMN arrays are superimposed onto patches that facilitate their insertion into skin. However, due to wide variations in skin elasticity and the amount of hair on the skin, the arrays fabricated on the patch are often not completely inserted and large amount of loaded materials are not delivered. Here, we report "Microlancer", a novel micropillar based system by which patients can self-administer DMNs and which would also be capable of achieving 97 ± 2% delivery efficiency of the loaded drugs regardless of skin type or the amount of hair on the skin in less than a second.

Show MeSH
Microscopy images and histological examinations of hairy and hairless pig cadaver skin.(a) Hairless pig cadaver skin before DMN insertion. (b) 50-μm insertion of 600-μm-tall DMN. The DMN was inserted 650 μm deep into the skin. (c) The base area of the DMN that was inserted 100 μm deep was less apparent on the skin surface compared with those inserted 50 μm deep. Histological examination showed that the DMNs were inserted 700 μm deep into the skin. (d) Hairy pig cadaver skin before DMN insertion. (e) The appearance of DMNs inserted 50 μm deep into hairy skin was similar to the appearance of DMNs inserted into hairless pig cadaver skin. (f) DMNs inserted 100 μm deep into the hairy pig cadaver skin penetrated 700 μm deep. Scale bars: microscopy images, 2 mm; histological images, 500 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4300505&req=5

f3: Microscopy images and histological examinations of hairy and hairless pig cadaver skin.(a) Hairless pig cadaver skin before DMN insertion. (b) 50-μm insertion of 600-μm-tall DMN. The DMN was inserted 650 μm deep into the skin. (c) The base area of the DMN that was inserted 100 μm deep was less apparent on the skin surface compared with those inserted 50 μm deep. Histological examination showed that the DMNs were inserted 700 μm deep into the skin. (d) Hairy pig cadaver skin before DMN insertion. (e) The appearance of DMNs inserted 50 μm deep into hairy skin was similar to the appearance of DMNs inserted into hairless pig cadaver skin. (f) DMNs inserted 100 μm deep into the hairy pig cadaver skin penetrated 700 μm deep. Scale bars: microscopy images, 2 mm; histological images, 500 μm.

Mentions: Histological examination was performed to verify that the targeted skin insertion depth correlated with the actual skin insertion depth. We chose 50 and 100 μm insertion depths to study the accuracy of the Microlancer. To facilitate the sectioning process, we treated the skin with 10% methylene blue dye solution. In subsequent trials, hairless pig cadaver skin was used as a mimic to human skin (Fig. 3a). DMNs (h = 600 μm) inserted 50 μm deep into hairless skin were clearly visible beneath the skin; these DMNs pierced an average distance of 650 ± 10 μm (Fig. 3b). DMNs that were inserted 100 μm into the skin were less apparent on microscopy. Histological examination indicated that these DMNs had penetrated 700 ± 20 μm into the skin (Fig. 3c). To ensure the reproducibility and accuracy of the Microlancer, regardless of skin type or the amount of hair on the skin, we performed a similar set of experiments using hairy pig cadaver skin (Fig. 3d). The DMNs that were inserted 50 μm deep into the hairy skin yielded insertion spots that were similar to the appearance of the spot array on the hairless skin, with an average insertion depth of 650 ± 10 μm (Fig. 3e). In addition, histological examinations of the DMNs inserted 100 μm deep into the hairy skin also yielded similar result to those inserted into hairless skin (Fig. 3f).


A patchless dissolving microneedle delivery system enabling rapid and efficient transdermal drug delivery.

Lahiji SF, Dangol M, Jung H - Sci Rep (2015)

Microscopy images and histological examinations of hairy and hairless pig cadaver skin.(a) Hairless pig cadaver skin before DMN insertion. (b) 50-μm insertion of 600-μm-tall DMN. The DMN was inserted 650 μm deep into the skin. (c) The base area of the DMN that was inserted 100 μm deep was less apparent on the skin surface compared with those inserted 50 μm deep. Histological examination showed that the DMNs were inserted 700 μm deep into the skin. (d) Hairy pig cadaver skin before DMN insertion. (e) The appearance of DMNs inserted 50 μm deep into hairy skin was similar to the appearance of DMNs inserted into hairless pig cadaver skin. (f) DMNs inserted 100 μm deep into the hairy pig cadaver skin penetrated 700 μm deep. Scale bars: microscopy images, 2 mm; histological images, 500 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4300505&req=5

f3: Microscopy images and histological examinations of hairy and hairless pig cadaver skin.(a) Hairless pig cadaver skin before DMN insertion. (b) 50-μm insertion of 600-μm-tall DMN. The DMN was inserted 650 μm deep into the skin. (c) The base area of the DMN that was inserted 100 μm deep was less apparent on the skin surface compared with those inserted 50 μm deep. Histological examination showed that the DMNs were inserted 700 μm deep into the skin. (d) Hairy pig cadaver skin before DMN insertion. (e) The appearance of DMNs inserted 50 μm deep into hairy skin was similar to the appearance of DMNs inserted into hairless pig cadaver skin. (f) DMNs inserted 100 μm deep into the hairy pig cadaver skin penetrated 700 μm deep. Scale bars: microscopy images, 2 mm; histological images, 500 μm.
Mentions: Histological examination was performed to verify that the targeted skin insertion depth correlated with the actual skin insertion depth. We chose 50 and 100 μm insertion depths to study the accuracy of the Microlancer. To facilitate the sectioning process, we treated the skin with 10% methylene blue dye solution. In subsequent trials, hairless pig cadaver skin was used as a mimic to human skin (Fig. 3a). DMNs (h = 600 μm) inserted 50 μm deep into hairless skin were clearly visible beneath the skin; these DMNs pierced an average distance of 650 ± 10 μm (Fig. 3b). DMNs that were inserted 100 μm into the skin were less apparent on microscopy. Histological examination indicated that these DMNs had penetrated 700 ± 20 μm into the skin (Fig. 3c). To ensure the reproducibility and accuracy of the Microlancer, regardless of skin type or the amount of hair on the skin, we performed a similar set of experiments using hairy pig cadaver skin (Fig. 3d). The DMNs that were inserted 50 μm deep into the hairy skin yielded insertion spots that were similar to the appearance of the spot array on the hairless skin, with an average insertion depth of 650 ± 10 μm (Fig. 3e). In addition, histological examinations of the DMNs inserted 100 μm deep into the hairy skin also yielded similar result to those inserted into hairless skin (Fig. 3f).

Bottom Line: Dissolving microneedles (DMNs) are polymeric, microscopic needles that deliver encapsulated drugs in a minimally invasive manner.However, due to wide variations in skin elasticity and the amount of hair on the skin, the arrays fabricated on the patch are often not completely inserted and large amount of loaded materials are not delivered.Here, we report "Microlancer", a novel micropillar based system by which patients can self-administer DMNs and which would also be capable of achieving 97 ± 2% delivery efficiency of the loaded drugs regardless of skin type or the amount of hair on the skin in less than a second.

View Article: PubMed Central - PubMed

Affiliation: Department of Biotechnology, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-749, Korea.

ABSTRACT
Dissolving microneedles (DMNs) are polymeric, microscopic needles that deliver encapsulated drugs in a minimally invasive manner. Currently, DMN arrays are superimposed onto patches that facilitate their insertion into skin. However, due to wide variations in skin elasticity and the amount of hair on the skin, the arrays fabricated on the patch are often not completely inserted and large amount of loaded materials are not delivered. Here, we report "Microlancer", a novel micropillar based system by which patients can self-administer DMNs and which would also be capable of achieving 97 ± 2% delivery efficiency of the loaded drugs regardless of skin type or the amount of hair on the skin in less than a second.

Show MeSH