Integrating Carbon Nanomaterials with Metals for Bio-sensing Applications

Abstract

Age structure in most developed countries is changing fast as the average lifespan is increasing significantly, calling for solutions to provide improved treatments for age-related neurological diseases and disorders. In order to address these problems, a reliable way of recording information about neurotransmitters from in vitro and in vivo applications is needed to better understand neurological diseases and disorders as well as currently used treatments. Likewise, recent developments in medicine, especially with the opioid crisis, are demanding a swift move to personalized medicine to administer patient needs rather than population-wide averages. In order to enable the so-called personalized medicine, it is necessary to be able to do measurements in vivo and in real time. These actions require sensitive and selective detection of different analytes from very demanding environments. Current state-of-the-art materials are unable to provide sensitive and selective detection of neurotransmitters as well as the required time resolution needed for drug molecules at a reasonable cost. To meet these challenges, we have utilized different metals to grow carbon nanomaterials and applied them for sensing applications showing that there are clear differences in their electrochemical properties based on the selected catalyst metal. Additionally, we have combined atomistic simulations to support optimizing materials for experiments and to gain further understanding of the atomistic level reactions between different analytes and the sensor surface. With carbon nanostructures grown from Ni and Al + Co + Fe hybrid, we can detect dopamine, ascorbic acid, and uric acid simultaneously. On the other hand, nanostructures grown from platinum provide a feasible platform for detection of H2O2 making them suitable candidates for enzymatic biosensors for detection of glutamate, for example. Tetrahedral amorphous carbon electrodes have an ability to detect morphine, paracetamol, tramadol, and O-desmethyltramadol. With carbon nanomaterial-based sensors, it is possible to reach metal-like properties in sensing applications using only a fraction of the metal as seed for the material growth. We have also seen that by using nanodiamonds as growth catalyst for carbon nanofibers, it is not possible to detect dopamine and ascorbic acid simultaneously, although the morphology of the resulting nanofibers is similar to the ones grown using Ni. This further indicates the importance of the metal selection for specific applications. However, Ni as a continuous layer or as separate islands does not provide adequate performance. Thus, it appears that metal nanoparticles combined with fiber-like morphology are needed for optimized sensor performance for neurotransmitter detection. This opens up a new research approach of application-specific nanomaterials, where carefully selected metals are integrated with carbon nanomaterials to match the needs of the sensing application in question.

Effect of Electrochemical Oxidation on Physicochemical Properties of Fe‐Containing Single‐Walled Carbon Nanotubes

“…We have previously shown that the metal catalysts in carbon nanomaterials have an essential role in the sensitivity and selectivity towards a different biomolecules, which cannot be achieved only with pure carbon. [15,16] Furthermore, we have extensively studied the suitability of pristine iron containing single-walled carbon nanotubes (SWCNTs) for the detection of various analgesics. [7][8][9] Despite these studies, at this stage, there are no clear indications regarding the required amount of iron that enhances electrocatalysis towards opioids, and whether the electrocatalytic properties of Fe-SWCNTs be improved with simple oxidative pretreatment.…”

“…It is well known that metals can catalyze various electrochemical reactions. We have previously shown that the metal catalysts in carbon nanomaterials have an essential role in the sensitivity and selectivity towards a different biomolecules, which cannot be achieved only with pure carbon . Furthermore, we have extensively studied the suitability of pristine iron containing single‐walled carbon nanotubes (SWCNTs) for the detection of various analgesics .…”

Smart Hydrogels Meet Carbon Nanomaterials for New Frontiers in Medicine

“…They are also very promising for tissue engineering [ 54 ], especially for bone [ 55 ], and for conductive cells, such as the cardiac [ 56 , 57 ] and nerve tissues [ 58 , 59 ]. Their potential uses in clinical applications [ 60 ] and sensing [ 61 ] have been recently reviewed. Therefore, this article will focus solely on the very latest developments regarding innovative biomedical uses of carbon nanomaterials in the form of smart hydrogels.…”

Self-Assembling Peptides and Carbon Nanomaterials Join Forces for Innovative Biomedical Applications

“…As a result, they have attracted great interest for their innovative potential in areas of unmet clinical need [ 74 , 76 ], such as oncology [ 77 ], infections [ 78 ], and tissue engineering [ 79 ], especially for conductive nerve [ 80 , 81 ] and cardiac [ 82 , 83 ] tissues, but also bone [ 84 ]. Their potential applications in sensing [ 85 ] and, generally, in clinical applications [ 86 ] are also widely studied.…”