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pHEMA Encapsulated PEDOT-PSS-CNT Microsphere Microelectrodes for Recording Single Unit Activity in the Brain.

Castagnola E, Maggiolini E, Ceseracciu L, Ciarpella F, Zucchini E, De Faveri S, Fadiga L, Ricci D - Front Neurosci (2016)

Bottom Line: This enhancement significantly reduces the size of the implantable device though preserving excellent electrical performances.Moreover, the spherical shape of the electrode together with the surface area increase provided by the nanocomposite deposited on it, maximize the electrical contact and may improve recording stability over time.These results have a good potential to contribute to fulfill the grand challenge of obtaining stable neural interfaces for long-term applications.

View Article: PubMed Central - PubMed

Affiliation: Center for Translational Neurophysiology of Speech and Communication, Istituto Italiano di Tecnologia Ferrara, Italy.

ABSTRACT
The long-term reliability of neural interfaces and stability of high-quality recordings are still unsolved issues in neuroscience research. High surface area PEDOT-PSS-CNT composites are able to greatly improve the performance of recording and stimulation for traditional intracortical metal microelectrodes by decreasing their impedance and increasing their charge transfer capability. This enhancement significantly reduces the size of the implantable device though preserving excellent electrical performances. On the other hand, the presence of nanomaterials often rises concerns regarding possible health hazards, especially when considering a clinical application of the devices. For this reason, we decided to explore the problem from a new perspective by designing and testing an innovative device based on nanostructured microspheres grown on a thin tether, integrating PEDOT-PSS-CNT nanocomposites with a soft synthetic permanent biocompatible hydrogel. The pHEMA hydrogel preserves the electrochemical performance and high quality recording ability of PEDOT-PSS-CNT coated devices, reduces the mechanical mismatch between soft brain tissue and stiff devices and also avoids direct contact between the neural tissue and the nanocomposite, by acting as a biocompatible protective barrier against potential nanomaterial detachment. Moreover, the spherical shape of the electrode together with the surface area increase provided by the nanocomposite deposited on it, maximize the electrical contact and may improve recording stability over time. These results have a good potential to contribute to fulfill the grand challenge of obtaining stable neural interfaces for long-term applications.

No MeSH data available.


Related in: MedlinePlus

Fluorescence microscopy images of tracks for non-encapsulated (left panels) and pHEMA-encapsulated (right panels) microspheres, 2 and 4 weeks after the implant. (A,B) show the ED1-positive cells (red) at 20 × at 2 weeks; (C,D) show the ED1-positive cells (red) at 20 × at 4 weeks.
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Figure 11: Fluorescence microscopy images of tracks for non-encapsulated (left panels) and pHEMA-encapsulated (right panels) microspheres, 2 and 4 weeks after the implant. (A,B) show the ED1-positive cells (red) at 20 × at 2 weeks; (C,D) show the ED1-positive cells (red) at 20 × at 4 weeks.

Mentions: As shown in Figures 9, 10, at both 2 and 4 post-implant weeks and for both types of microelectrode, the number of GFAP stained cell nuclei surrounding the tracks was increased (Figures 9C,D, 10C,D), but without any detectable neuronal loss (Figures 9E,F, 10E,F). Few ED1-positive cells were observed at 2 post-implant weeks in proximity of tracks for both type of microelectrodes (Figures 11A,B), while no evidence of ED1-positive cells was identified at 4 weeks (Figures 11C,D).


pHEMA Encapsulated PEDOT-PSS-CNT Microsphere Microelectrodes for Recording Single Unit Activity in the Brain.

Castagnola E, Maggiolini E, Ceseracciu L, Ciarpella F, Zucchini E, De Faveri S, Fadiga L, Ricci D - Front Neurosci (2016)

Fluorescence microscopy images of tracks for non-encapsulated (left panels) and pHEMA-encapsulated (right panels) microspheres, 2 and 4 weeks after the implant. (A,B) show the ED1-positive cells (red) at 20 × at 2 weeks; (C,D) show the ED1-positive cells (red) at 20 × at 4 weeks.
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4834343&req=5

Figure 11: Fluorescence microscopy images of tracks for non-encapsulated (left panels) and pHEMA-encapsulated (right panels) microspheres, 2 and 4 weeks after the implant. (A,B) show the ED1-positive cells (red) at 20 × at 2 weeks; (C,D) show the ED1-positive cells (red) at 20 × at 4 weeks.
Mentions: As shown in Figures 9, 10, at both 2 and 4 post-implant weeks and for both types of microelectrode, the number of GFAP stained cell nuclei surrounding the tracks was increased (Figures 9C,D, 10C,D), but without any detectable neuronal loss (Figures 9E,F, 10E,F). Few ED1-positive cells were observed at 2 post-implant weeks in proximity of tracks for both type of microelectrodes (Figures 11A,B), while no evidence of ED1-positive cells was identified at 4 weeks (Figures 11C,D).

Bottom Line: This enhancement significantly reduces the size of the implantable device though preserving excellent electrical performances.Moreover, the spherical shape of the electrode together with the surface area increase provided by the nanocomposite deposited on it, maximize the electrical contact and may improve recording stability over time.These results have a good potential to contribute to fulfill the grand challenge of obtaining stable neural interfaces for long-term applications.

View Article: PubMed Central - PubMed

Affiliation: Center for Translational Neurophysiology of Speech and Communication, Istituto Italiano di Tecnologia Ferrara, Italy.

ABSTRACT
The long-term reliability of neural interfaces and stability of high-quality recordings are still unsolved issues in neuroscience research. High surface area PEDOT-PSS-CNT composites are able to greatly improve the performance of recording and stimulation for traditional intracortical metal microelectrodes by decreasing their impedance and increasing their charge transfer capability. This enhancement significantly reduces the size of the implantable device though preserving excellent electrical performances. On the other hand, the presence of nanomaterials often rises concerns regarding possible health hazards, especially when considering a clinical application of the devices. For this reason, we decided to explore the problem from a new perspective by designing and testing an innovative device based on nanostructured microspheres grown on a thin tether, integrating PEDOT-PSS-CNT nanocomposites with a soft synthetic permanent biocompatible hydrogel. The pHEMA hydrogel preserves the electrochemical performance and high quality recording ability of PEDOT-PSS-CNT coated devices, reduces the mechanical mismatch between soft brain tissue and stiff devices and also avoids direct contact between the neural tissue and the nanocomposite, by acting as a biocompatible protective barrier against potential nanomaterial detachment. Moreover, the spherical shape of the electrode together with the surface area increase provided by the nanocomposite deposited on it, maximize the electrical contact and may improve recording stability over time. These results have a good potential to contribute to fulfill the grand challenge of obtaining stable neural interfaces for long-term applications.

No MeSH data available.


Related in: MedlinePlus