MSc thesis project proposal

A Microneedle Probe for Optical Blood Analysis

Our target application is in the detection of jaundice. Existing methods for non-invasive detection of jaundice use optical reflection spectrometry to the measure the skin discoloration, caused by the bilirubin in the blood [1]. Bilirubin is a yellow pigment formed by the breakdown of dead red blood cells in the liver. An increased level of bilirubin in the blood indicates serious problems with the liver as often occurs with newborns [2]. The epidermis forms an efficient barrier for light and a very large difference in optical properties can be observed e.g. by roughness, wrinkles and skin pigmentation [3]. Existing instruments for the detection of bilirubin by skin surface spectrometry are therefore rather inaccurate [4][5]. The proposed microneedles bypass the superficial skin and give better access to the bilirubin in the blood. Epidermal microneedles can be short and minimally invasive. The microneedles are placed in a bandage on the tip of an optical probe that can be connected by a optical fiber cable to a spectrometer.


Research on the optical and mechanical design of different geometries of the needles using biocompatible polymers such as SU8. Fabrication of probe tips and their integration with an optical fiber cable. Characterization in the lab and by clinical tests by spectral measurements using commercially available USB micro spectrometers. Building a handheld prototype that can be used by our partners for field tests on patients.


The project will concentrate on the design, fabrication and testing of the optically transparent microneedles using biocompatible polymers such as SU8. The design and fabrication of such probe tips is quite a challenge and requires much new work. The probe tip should be robust, low cost and disposable. Globally the work will be divided in the following steps:  Design of optically transparent microneedles..  Fabrication of the microneedles using biocompatible polymers such as SU8.  Testing and characterization using a commercially available USB micro spectrometer and fibers.  Field tests with our partners. Success in this project would lead to a low cost portable system that can avoid blood tests and can be used for early detection of jaundice.

Contact Ger de Graaf

Electronic Instrumentation Group

Department of Microelectronics

Last modified: 2018-12-17