Additive manufacturing or 3D printing is rapidly growing in popularity. This growth brings increased interest in studying the byproducts released during 3D printing. In this work, we present a new method to collect and analyze the metal composition of individual particles released during the operation of fused deposition modeling (FDM) 3D printers using single-particle inductively coupled plasma time-of-flight mass spectrometry (spICP-TOFMS).
View Article and Find Full Text PDFIn this communication, we demonstrate the electrical detection of SARS-CoV-2 RNA at low femtomolar concentrations without labels or amplification reactions. Following its extraction from virus particles, the viral RNA was electrokinetically preconcentrated (100-fold) within a packed bed of probe-modified microbeads. This preconcentration was accomplished by counter-flow focusing of the RNA along an electric field gradient generated by faradaic ion concentration polarization (fICP).
View Article and Find Full Text PDFCholinergic signaling, i.e., neurotransmission mediated by acetylcholine, is involved in a host of physiological processes, including learning and memory.
View Article and Find Full Text PDFIn this paper, we report a method to integrate the electrokinetic pre-enrichment of nucleic acids within a bed of probe-modified microbeads with their label-free electrochemical detection. In this detection scheme, hybridization of locally enriched target nucleic acids to the beads modulates the conduction of ions along the bead surfaces. This is a fundamental advancement in that this mechanism is similar to that observed in nanopore sensors, yet occurs in a bed of microbeads with microscale interstices.
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