Abstract

Optical poration, or drilling, of the human nail has the potential to drastically improve transungual drug delivery. However, this approach is accompanied by thermal damage to the nail tissue surrounding the laser radiation-created pore. In this paper, fluorescence microscopy has been employed to quantitatively evaluate thermal damage to the nail induced by laser ablation with 80 MHz, nano-Joule, femtosecond pulses delivered via a hollow-core fiber. An empirical relation has been established between the intensity of the resulting fluorescence signal and temperature to which the nail was exposed. Using this relationship, detailed temperature maps have been created of the areas surrounding the pores, enabling the mechanism of poration to be better understood. It was deduced that plasma-mediated ablation is primarily responsible for nail tissue ablation at the centre of the pore, while cumulative photothermal processes dominate at the pore edges. It is concluded, furthermore, that temperature mapping represents a useful new tool with which to optimize the process of nail poration. The method is potentially generic and may be applicable to other biological materials.
LanguageEnglish
Number of pages12
JournalDrug Delivery and Translational Research
DOIs
StatusPublished - 23 Apr 2019

Keywords

  • human nail
  • femtosecond pulsed laser ablation
  • nail poration
  • fluorescence microscopy
  • thermal mapping
  • drug delivery

Cite this

@article{e54e3750bd3a4c07b7edc97938169ed5,
title = "Mechanism of human nail poration by high-repetition-rate, femtosecond laser ablation",
abstract = "Optical poration, or drilling, of the human nail has the potential to drastically improve transungual drug delivery. However, this approach is accompanied by thermal damage to the nail tissue surrounding the laser radiation-created pore. In this paper, fluorescence microscopy has been employed to quantitatively evaluate thermal damage to the nail induced by laser ablation with 80 MHz, nano-Joule, femtosecond pulses delivered via a hollow-core fiber. An empirical relation has been established between the intensity of the resulting fluorescence signal and temperature to which the nail was exposed. Using this relationship, detailed temperature maps have been created of the areas surrounding the pores, enabling the mechanism of poration to be better understood. It was deduced that plasma-mediated ablation is primarily responsible for nail tissue ablation at the centre of the pore, while cumulative photothermal processes dominate at the pore edges. It is concluded, furthermore, that temperature mapping represents a useful new tool with which to optimize the process of nail poration. The method is potentially generic and may be applicable to other biological materials.",
keywords = "human nail, femtosecond pulsed laser ablation, nail poration, fluorescence microscopy, thermal mapping, drug delivery",
author = "Simon Vanstone and Jim Stone and Sergey Gordeev and Richard Guy",
year = "2019",
month = "4",
day = "23",
doi = "10.1007/s13346-019-00638-x",
language = "English",
journal = "Drug Delivery and Translational Research",
issn = "2190-393X",
publisher = "Springer Publishing Company",

}

TY - JOUR

T1 - Mechanism of human nail poration by high-repetition-rate, femtosecond laser ablation

AU - Vanstone, Simon

AU - Stone, Jim

AU - Gordeev, Sergey

AU - Guy, Richard

PY - 2019/4/23

Y1 - 2019/4/23

N2 - Optical poration, or drilling, of the human nail has the potential to drastically improve transungual drug delivery. However, this approach is accompanied by thermal damage to the nail tissue surrounding the laser radiation-created pore. In this paper, fluorescence microscopy has been employed to quantitatively evaluate thermal damage to the nail induced by laser ablation with 80 MHz, nano-Joule, femtosecond pulses delivered via a hollow-core fiber. An empirical relation has been established between the intensity of the resulting fluorescence signal and temperature to which the nail was exposed. Using this relationship, detailed temperature maps have been created of the areas surrounding the pores, enabling the mechanism of poration to be better understood. It was deduced that plasma-mediated ablation is primarily responsible for nail tissue ablation at the centre of the pore, while cumulative photothermal processes dominate at the pore edges. It is concluded, furthermore, that temperature mapping represents a useful new tool with which to optimize the process of nail poration. The method is potentially generic and may be applicable to other biological materials.

AB - Optical poration, or drilling, of the human nail has the potential to drastically improve transungual drug delivery. However, this approach is accompanied by thermal damage to the nail tissue surrounding the laser radiation-created pore. In this paper, fluorescence microscopy has been employed to quantitatively evaluate thermal damage to the nail induced by laser ablation with 80 MHz, nano-Joule, femtosecond pulses delivered via a hollow-core fiber. An empirical relation has been established between the intensity of the resulting fluorescence signal and temperature to which the nail was exposed. Using this relationship, detailed temperature maps have been created of the areas surrounding the pores, enabling the mechanism of poration to be better understood. It was deduced that plasma-mediated ablation is primarily responsible for nail tissue ablation at the centre of the pore, while cumulative photothermal processes dominate at the pore edges. It is concluded, furthermore, that temperature mapping represents a useful new tool with which to optimize the process of nail poration. The method is potentially generic and may be applicable to other biological materials.

KW - human nail

KW - femtosecond pulsed laser ablation

KW - nail poration

KW - fluorescence microscopy

KW - thermal mapping

KW - drug delivery

U2 - 10.1007/s13346-019-00638-x

DO - 10.1007/s13346-019-00638-x

M3 - Article

JO - Drug Delivery and Translational Research

T2 - Drug Delivery and Translational Research

JF - Drug Delivery and Translational Research

SN - 2190-393X

ER -