Nanopillar Based Enhanced-Fluorescence Detection of Surface-Immobilized Beryllium

Abstract

The unique properties associated with beryllium metal ensures the continued use in many industries despite the documented health and environmental risks. While engineered safeguards and personal protective equipment can reduce risks associated with working with the metal, it has been mandated by the Environmental Protection Agency (EPA) and Occupational Safety and Health Administration (OSHA) that the workplace air and surfaces must be monitored for toxic levels. While many methods have been developed to monitor levels down to the low μg/m(3), the complexity and expense of these methods have driven the investigation into alternate methodologies. Herein, we use a combination of the previously developed fluorescence Be(II) ion detection reagent, 10-hydroxybenzo[h]quinoline (HBQ), with an optical field enhanced silicon nanopillar array, creating a new surface immobilized (si-HBQ) platform. The si-HBQ platform allows the positive control of the reagent for demonstrated reusability and a pillar diameter based tunable enhancement. Furthermore, native silicon nanopillars are overcoated with thin layers of porous silicon oxide to develop an analytical platform capable of a 0.0006 μg/L limit of detection (LOD) using sub-μL sample volumes. Additionally, we demonstrate a method to multiplex the introduction of the sample to the platform, with minimal 5.2% relative standard deviation (RSD) at 0.1 μg/L, to accommodate the potentially large number of samples needed to maintain industrial compliance. The minimal sample and reagent volumes and lack of complex and highly specific instrumentation, as well as positive control and reusability of traditionally consumable reagents, create a platform that is accessible and economically advantageous.

Surface Modification of Silicon Pillar Arrays To Enhance Fluorescence Detection of Uranium and DNA

“…To meet these high demands, we decided to use a platform that may compromise some of the optimized enhancement for quickly fabricated vast pillar array substrates, namely, stochastic platinum DW pillar arrays, whose usefulness has been previously expounded upon. 6 , 24 , 25 To create these arrays, we first needed to determine the optimum pillar diameter range.…”

Biomimetic Nanopillar-Based Biosensor for Label-Free Detection of Influenza A Virus

“…Based on the excellent properties of nanopillar structures, Charlton et al . developed optical field-enhanced silicon nanopillars for the detection of DNA [ 27 ]. Lee et al .…”

“…In addition, nanopillar structures can be fabricated by nanoimprint lithography, a two-dimensional nanostructure manufacturing technique that enables simple, low-cost, and high-throughput production [22][23][24][25][26]. Based on the excellent properties of nanopillar structures, Charlton et al developed optical field-enhanced silicon nanopillars for the detection of DNA [27]. Lee et al reported a localized surface plasmon resonance nanopillar biosensor prepared by nanoimprint lithography [28].…”

A New Ion Pair-based Surfactant-assisted Dispersive Liquid-Liquid Microextraction of Ultratrace Levels of Beryllium From Natural and Effluent Samples Followed by ETAAS Determination

“…throneas as chelating agents and extraction by using micelle and mixed micelles-based cloud point extraction (7,(10)(11)(12)(13). Recently, hydroxybenzoquinoline fluorescent chelating agents immobilized in a silica nanopiller platform and silica gel-loaded column have been used for extraction of beryllium (14,15). Nevertheless, these are time-consuming methods, and routine analysis is not possible.…”