Affordable method for making Silicon Nitride Nanopore with Simple Chemical Etching (ACS Nano, 2022)

We demonstrated DNA translocations through silicon nitride pores formed by simple chemical etching on glass substrates using microscopic amounts of hydrofluoric acid. DNA translocations and transmission electron microscopy (TEM) prove the fabrication of nanopores and allow their characterization. This simple and affordable chemical method for making solid-state nanopores accelerates their adoption for molecule sensing and characterization applications. 

TEM images of chemically-etched Silicon Nitride Nanopores and DNA translocation traces through these single pores

Detection of 1-nm-size small drug molecules with nanopores (ibuprofen and sulfamethoxazole)

We used nanopores for detection of 1-nm-size small drugs, ibuprofen (33 atoms) and sulfamethoxazole (28 atoms), by binding them to a protein (BSA), otherwise they are directly undetectable. Both are used for treating pain and inflammation, and bind to BSA efficiently. One reason why this is relevant and the idea can be extended to other small drugs is that unused pills dumped into toilets, and medications excreted through urine, end up in some amounts in our water supply even after treatments and have consequences on living organisms. Zehui Xia, et al., “Protein-enabled detection of ibuprofen and sulfamethoxazole using solid-state nanopores”, Proteomics, 2022, 2100071.

Zehui Xia’s new NASA STTR water monitoring project covered by Philadelphia

Xia has been working in research and development at Geoppert — a five-person operation based in Logan Square — since 2019, when she received her Ph.D. from University of Massachusetts Amherst. Xia’s research will ultimately lead to a “portable mini-lab that will identify and remove contaminants down to the molecular level, and which can endure the shock and vibration of sub-orbital flight,” per a spokesperson. The technology could potentially be used on future manned missions to the moon and Mars.

Paige Gross for Philadelphia

Research Papers Using Goeppert’s Technology

Invited Article & Cover Art for March 2020 Issue: Detection of single analyte and environmental samples with silicon nitride nanopores: Antarctic dirt particulates and DNA in artificial seawater, David J. NiedzwieckiYung-Chien ChouZehui XiaFederico Thei and Marija Drndić, Review of Scientific Instruments 91, 031301 (2020). 

AIP Scilight:

Accelerated by Goeppert’s nanochannel chips: 60-100 nm diameter SiN, 100-nm-thick: Translocation of soft phytoglycogen nanoparticles through solid-state nanochannels, W. R. Lenart, W. Kong, W. C. Oltjena, M. J. A. Hore, J. of Mat. Chem. B, 41, (2019).!divAbstract

Goeppert’s SiN pores featured by Dekker lab in “Nanopores–a Versatile Tool to Study Protein Dynamics” by Sonja Schmid & Cees Dekker – arXiv preprint arXiv:2010.07399, 2020.

Exciting work from Dekker lab at Delft University of Technology on trapping proteins using a DNA-origami sphere (shown as a big red ball) and a solid-state nanopore. This “NEOtrap” was facilitated also by Goeppert’s 20-nm-thick SiN chips (

Link to paper:

Nuclear pore complexes (NPCs) that regulate selective transport between the nucleus and the cytoplasm. Study facilitated by Goeppert’s products. Published in Nature Communications 2021, by researchers in Netherlands and Sweden. Accelerating science together. Link to paper:

Goeppert cited for its advance in solid state nanopore sensors.