Polymeric micro needles have been explored for transdermal drug delivery, neural stimulation, and electrochemical biosensors. Thepolymeric microneedles as electrochemical biosensors can offer a wide array of advantages like easy miniaturization and functionalization, minimal invasiveness for painless applications and applicability in wide range of analytes testing through biofluids. However, design and fabrication of polymeric microneedles suffer from their inherent poor mechanical properties and scalable fabrication. This affects their successful deployment as electrochemical biosensor. Hence, in the current work, we have investigated the mechanical properties of several polymeric microneedle design throughfinite element method (FEM) and then used 3D printing to fabricate microneedle array. A 3D conical shapes of 2 mm length of microneedle having 10 µm tip and 300 µm base diameter made up of different polymers have been modeled in ANSYS. Thereafter, these models were evaluated for stress distribution, skin puncture and critical buckling load analysis. Further, a comparative analysis of different shapes of microneedle with these polymerswere performed to understand role of shape in penetration of skin and failure of microneedle. Polylactic acid (PLA) and polycarbonate (PC) showed the promising result in a conical design. Thereafter, we fabricated the PLA microneedle array with 3D printer and characterized it though Scanning Electron microscopy (SEM), mechanical testing, functionalization and skin penetration test.The 3D printed microneedle array showed promising result to be deployed as electrochemical sensor.

Material design and characterization of an array of polymeric microneedles for developing wearable electrochemical biosensors

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.