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Single-wall carbon nanotubes (SWNT) have a strong and stable near-infrared (nIR) signal and can interact with target analytes selectively, even at the single molecule level, to alter fluorescence intensity and/or emission peak wavelength. SWNT have been employed as nIR optical sensors for detecting a variety of analytes. However, high cost, long fabrication time, and poor fluorescence yield limit the current methods for immobilizing SWNT sensors on solid substrates. Recently, our group reported a protocol for SWNT immobilization resulting in high fluorescence yield, signal longevity, fluorescence distribution, and quick sensing response time. However, it takes 5 days to fabricate these sensor arrays. We have improved our previously reported protocol to immobilize SWNT sensors with a method that takes only 2 days, results in a platform with similar surface morphology, and has a higher fluorescence intensity than the previous platforms without sacrificing the sensing capabilities.
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Development of sterile platform for quantification of extracellular analytes via single walled carbon nanotubes
Progress has been made studying cell-cell signaling communication processes. However, due to limitations of current sensors on time and spatial resolution, the role of many extracellular analytes is still unknown. A single walled carbon nanotube (SWNT) platform was previously developed based on the avidin-biotin immobilization of SWNT to a glass substrate. The SWNT platform provides real time feedback about analyte concentration and has a high concentration of evenly distributed sensors, both of which are essential for the study of extracellular analytes. Unfortunately, this initial SWNT platform is synthesized through unsterile conditions and cannot be sterilized post-production due to the delicate nature of the sensors, making it unsuitable for in vitro work. Herein the multiple-step process for SWNT immobilization is modified and the platform’s biocompatibility is assessed in terms of sterility, cytotoxicity, cell proliferation, and cell morphology through comparison with non-sensors controls. The results demonstrate the SWNT platform’s sterility and lack of toxicity over 72 h. The proliferation rate and morphology profiles for cells growing on the SWNT platform are similar to those grown on tissue culture substrates. This novel nano-sensor platform preserves cell health and cell functionality over time, offering opportunities to study extracellular analytes gradients in cellular communication.
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- PAR ID:
- 10516918
- Publisher / Repository:
- Analytical Biochemistry
- Date Published:
- Journal Name:
- Analytical Biochemistry
- Volume:
- 693
- Issue:
- C
- ISSN:
- 0003-2697
- Page Range / eLocation ID:
- 115582
- Subject(s) / Keyword(s):
- Single walled carbon nanotubes Immobilization method Extracellular analytes Biosensors Nanoarrays Biocompatibility
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.ab.2024.115582
