Fabrication and characterization of gold-coated solid silicon microneedles with improved biocompatibility

  • S. Pradeep NarayananEmail author
  • S. Raghavan


In this paper, we discussed biocompatibility improvement and mechanical strength of the solid silicon (Si) microneedles for transdermal drug delivery systems. The pyramidal shape and sharp tip of microneedles are fabricated using an optimized Tetramethylammonium Hydroxide (TMAH) etching factors. The mechanical strength and biocompatibility of the microneedle array are enhanced after coating gold (Au) layer through metal sputtering technique. The needles thus fabricated are suitable for sustained transdermal drug delivery applications with a height of 250 μm and a base width of 52.8 μm, the aspect ratio of 4.73, and tip angle and diameter of 24.5° and 45 μm. The Vickers hardness value of 3800 Hv is obtained for the fabricated Au-coated solid Si microneedles. The attained Vickers hardness value is substantially higher than the skin resistive force. It shows that the capability of drug delivery by piercing these microneedles into the skin becomes readily feasible.


Biocompatibility Hardness Metal sputtering Microneedles Transdermal drug delivery 


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The authors gratefully acknowledge the support provided by the Indian Nanoelectronics Users Programme (INUP)—IIT Bombay (IITB), India, to carry out this work and also to CEN (Centre of Excellence in Nano Technology), IITB, for their permission to use the available facilities.


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© Springer-Verlag London Ltd., part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Electronics and Communication EngineeringKalasalingam Academy of Research and EducationKrishnan KovilIndia
  2. 2.Department of Electronics and Communication EngineeringNational Institute of TechnologyTiruchirappalliIndia

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