Mechanical Characterization of Individual Needles in Microneedle Arrays: Factors Affecting Compression Test Results

<b>Background:</b> This study aims to investigate the impact of test conditions on the results of the compression testing of microneedle arrays (MNAs). <b>Methods:</b> Uniaxial compression tests were conducted on polyglycolic acid-fabricated biodegradable MNAs. Load–displacem...

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Main Authors: Yusuke Tsuboko, Hideyuki Sakoda, Yoshihiro Okamoto, Yusuke Nomura, Eiichi Yamamoto
Format: Article
Language:English
Published: MDPI AG 2024-11-01
Series:Pharmaceutics
Subjects:
Online Access:https://www.mdpi.com/1999-4923/16/11/1480
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author Yusuke Tsuboko
Hideyuki Sakoda
Yoshihiro Okamoto
Yusuke Nomura
Eiichi Yamamoto
author_facet Yusuke Tsuboko
Hideyuki Sakoda
Yoshihiro Okamoto
Yusuke Nomura
Eiichi Yamamoto
author_sort Yusuke Tsuboko
collection DOAJ
description <b>Background:</b> This study aims to investigate the impact of test conditions on the results of the compression testing of microneedle arrays (MNAs). <b>Methods:</b> Uniaxial compression tests were conducted on polyglycolic acid-fabricated biodegradable MNAs. Load–displacement curves were obtained for varying conditions, including the number of microneedles (MNs) compressed simultaneously, compression speeds, and compression angles. Subsequently, the buckling load and stiffness were calculated, and the MN deformation during compression was observed. <b>Results:</b> The buckling load and stiffness per MN decreased significantly with a simultaneous increase in compressed MNs. The mean buckling load and stiffness of 52 MNs in single-needle compression tests were 0.211 ± 0.008 N and 13.9 ± 1.3 N/mm, respectively, with no variation among the three MNAs. However, a significant difference in buckling load and stiffness was observed among the MNs within the MNAs. Additionally, buckling loads and stiffnesses were significantly lower in certain MNs at the same location in different MNAs. Buckling load and stiffness decreased significantly during inclined compression compared to during vertical compression. While the tests evaluate the mechanical properties of MNAs, test results may vary depending on test conditions. <b>Conclusions:</b> Compression testing of the individual MNs comprising an MNA helps evaluate the mechanical properties of MNs and ensure the quality of MNAs.
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spelling doaj-art-a04fff7cbd8749ac8ab0f677c4b9bd402025-08-20T01:53:57ZengMDPI AGPharmaceutics1999-49232024-11-011611148010.3390/pharmaceutics16111480Mechanical Characterization of Individual Needles in Microneedle Arrays: Factors Affecting Compression Test ResultsYusuke Tsuboko0Hideyuki Sakoda1Yoshihiro Okamoto2Yusuke Nomura3Eiichi Yamamoto4Division of Medical Devices, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, JapanDivision of Medical Devices, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, JapanDivision of Medical Devices, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, JapanDivision of Medical Devices, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, JapanDivision of Medical Devices, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, Japan<b>Background:</b> This study aims to investigate the impact of test conditions on the results of the compression testing of microneedle arrays (MNAs). <b>Methods:</b> Uniaxial compression tests were conducted on polyglycolic acid-fabricated biodegradable MNAs. Load–displacement curves were obtained for varying conditions, including the number of microneedles (MNs) compressed simultaneously, compression speeds, and compression angles. Subsequently, the buckling load and stiffness were calculated, and the MN deformation during compression was observed. <b>Results:</b> The buckling load and stiffness per MN decreased significantly with a simultaneous increase in compressed MNs. The mean buckling load and stiffness of 52 MNs in single-needle compression tests were 0.211 ± 0.008 N and 13.9 ± 1.3 N/mm, respectively, with no variation among the three MNAs. However, a significant difference in buckling load and stiffness was observed among the MNs within the MNAs. Additionally, buckling loads and stiffnesses were significantly lower in certain MNs at the same location in different MNAs. Buckling load and stiffness decreased significantly during inclined compression compared to during vertical compression. While the tests evaluate the mechanical properties of MNAs, test results may vary depending on test conditions. <b>Conclusions:</b> Compression testing of the individual MNs comprising an MNA helps evaluate the mechanical properties of MNs and ensure the quality of MNAs.https://www.mdpi.com/1999-4923/16/11/1480buckling loadmechanical propertiessingle-needle compressiontest conditionquality control
spellingShingle Yusuke Tsuboko
Hideyuki Sakoda
Yoshihiro Okamoto
Yusuke Nomura
Eiichi Yamamoto
Mechanical Characterization of Individual Needles in Microneedle Arrays: Factors Affecting Compression Test Results
Pharmaceutics
buckling load
mechanical properties
single-needle compression
test condition
quality control
title Mechanical Characterization of Individual Needles in Microneedle Arrays: Factors Affecting Compression Test Results
title_full Mechanical Characterization of Individual Needles in Microneedle Arrays: Factors Affecting Compression Test Results
title_fullStr Mechanical Characterization of Individual Needles in Microneedle Arrays: Factors Affecting Compression Test Results
title_full_unstemmed Mechanical Characterization of Individual Needles in Microneedle Arrays: Factors Affecting Compression Test Results
title_short Mechanical Characterization of Individual Needles in Microneedle Arrays: Factors Affecting Compression Test Results
title_sort mechanical characterization of individual needles in microneedle arrays factors affecting compression test results
topic buckling load
mechanical properties
single-needle compression
test condition
quality control
url https://www.mdpi.com/1999-4923/16/11/1480
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AT yusukenomura mechanicalcharacterizationofindividualneedlesinmicroneedlearraysfactorsaffectingcompressiontestresults
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