Open Access. Powered by Scholars. Published by Universities.®

Biomedical Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 4 of 4

Full-Text Articles in Biomedical

A Note From The Editor, Daphne Fauber Nov 2020

A Note From The Editor, Daphne Fauber

Ideas: Exhibit Catalog for the Honors College Visiting Scholars Series

This piece is a letter from Daphne Fauber, the editor of this issue of Ideas. In the letter, the editor introduces the work of Dr. Paschalis Gkoupidenis as well as the moment in time in which his Visiting Scholars talk occurs.


Numerical And Analytical Modeling To Determine Performance Trade-Offs In Hydrogel-Based Ph Sensors, Piyush Dak, Muhammad Ashraful Alam May 2016

Numerical And Analytical Modeling To Determine Performance Trade-Offs In Hydrogel-Based Ph Sensors, Piyush Dak, Muhammad Ashraful Alam

Birck and NCN Publications

Hydrogel based pH sensors are promising candidates for implantable sensors due to their low-cost and biocompatibility. Despite their commercial potential and numerous theoretical/experimental reports, the trade-offs between different performance parameters are not well understood, and explicitly stated. In this work, we develop a numerical and analytical framework to show that there is a fundamental trade-off between the performance parameters i.e. sensitivity/dynamic range vs. response-time/response-asymmetry in hydrogel sensors under constrained swelling conditions. Specifically, we consider the effect of the gel parameters, such as the ionizable group density ( Nf) and its dissociation constant ( Ka), on the …


Electronic Desalting For Controlling The Ionic Environment In Droplet-Based Biosensing Platforms, Vikhram Vilasur Swaminathan, Piyush Dak, Bobby Reddy Jr, Eric Salm, Carlos Duarte-Guevara, Yu Zhong, Andrew Fischer, Yi-Shao Liu, Rashid Bashir Feb 2015

Electronic Desalting For Controlling The Ionic Environment In Droplet-Based Biosensing Platforms, Vikhram Vilasur Swaminathan, Piyush Dak, Bobby Reddy Jr, Eric Salm, Carlos Duarte-Guevara, Yu Zhong, Andrew Fischer, Yi-Shao Liu, Rashid Bashir

Birck and NCN Publications

The ability to control the ionic environment in saline waters and aqueous electrolytes is useful for desalination as well as electronic biosensing. We demonstrate a method of electronic desalting at micro-scale through on-chip micro electrodes. We show that, while desalting is limited in bulk solutions with unlimited availability of salts, significant desalting of ≥1 mM solutions can be achieved in sub-nanoliter volume droplets with diameters of ∼250 μm. Within these droplets, by using platinum-black microelectrodes and electrochemical surface treatments, we can enhance the electrode surface area to achieve >99% and 41% salt removal in 1 mM and 10 mM salt …


Theory Of ‘Selectivity’ Of Label-Free Nanobiosensors – A Geometro-Physical Perspective, Pradeep R. Nair, Muhammad A. Alam Jan 2010

Theory Of ‘Selectivity’ Of Label-Free Nanobiosensors – A Geometro-Physical Perspective, Pradeep R. Nair, Muhammad A. Alam

Birck and NCN Publications

Modern label-free biosensors are generally far more sensitive and require orders of magnitude less incubation time compared to their classical counterparts. However, a more important characteristic regarding the viability of this technology for applications in Genomics/Proteomics is defined by the ‘Selectivity’, i.e., the ability to concurrently and uniquely detect multiple target biomolecules in the presence of interfering species. Currently, there is no theory of Selectivity that allows optimization of competing factors and there are few experiments to probe this problem systematically. In this article, we use the elementary considerations of surface exclusion, diffusion limited transport, and void distribution function to …