Boron Doped NanoCrystalline Diamond Sensor Integrated Lab on a Chip Device for Blood Gas Sensing Using Electrochemical Approach

Abstract

Hydrogen sulfide (H2S) bioavailability and exogenous hydrogen sulfide therapy regulate numerous disease states including inflammation, cancer, cardiovascular, neurological and gastrointestinal diseases. This proposed work investigates and demonstrates new H2S detection techniques well suited to disease detection through a Lab on a Chip (LOC) approach. Currently, a novel chip has been designed to detect the level of H2S present in the blood. A unique LOC device has various parts which serve specific purposes. Three layers, liberation layer, silicone membrane and the trapping layer were bonded and integrated with electrodes at trapping layer. The micro-fabricated liberation layer was coated with the sulfide liberation buffer. The liberated gas was then passed via a highly selective polymer membrane and then collected at the final chamber for its quantification. The electrochemical detection was made possible at this chamber using boron doped nanocrystalline diamond electrode (BDUNCD) electrode. Detection using bare electrode has been investigated. This research specifically highlights the optimization of the sensor integrated lab on the chip device to detect sulfide in biological range in a water based sample. The limit of detection was shown to be 0.1 μM. In general, results showed that detection of H2S using this method was less labor intensive, fast and achievable with low cost.