Sarah Tonello

Shape memory electrospun nonwovens based on crosslinked poly(ε-caprolactone) for multifunctional biological applications

In this work we have explored the capabilities of an electrospun mat, realized in crosslinked poly(e-caprolactone), to be employed as a scaffold for specific biological applications. Its shape memory behavior was here exploited to easily control fiber orientation and to guide cellular alignment. Randomly oriented mats were transformed in a stable shape with various degrees of fiber alignment by simply varying the maximum strain applied throughout proper thermo-mechanical cycles. The effect of fiber alignment was investigated both on mechanical properties and on cell culture, through biological characterization done by using Neural Stem Cells derived from human iPSCs (induced Pluripotent Stem Cells). Further, thanks to the thermal stability of the microfibrous structure, it was possible to transfer, through inkjet printing on the electrospun, a biocompatible sensing element, which successfully allowed to monitor cell adhesion (L6 Myoblast) in an innovative way under dynamic conditions.In this work we have explored the capabilities of an electrospun mat, realized in crosslinked poly(e-caprolactone), to be employed as a scaffold for specific biological applications. Its shape memory behavior was here exploited to easily control fiber orientation and to guide cellular alignment. Randomly oriented mats were transformed in a stable shape with various degrees of fiber alignment by simply varying the maximum strain applied throughout proper thermo-mechanical cycles. The effect of fiber alignment was investigated both on mechanical properties and on cell culture, through biological characterization done by using Neural Stem Cells derived from human iPSCs (induced Pluripotent Stem Cells). Further, thanks to the thermal stability of the microfibrous structure, it was possible to transfer, through inkjet printing on the electrospun, a biocompatible sensing element, which successfully allowed to monitor cell adhesion (L6 Myoblast) in an innovative way under dynamic conditions.

Enhanced Sensing of Interleukin 8 by Stripping Voltammetry: Carbon Nanotubes versus Fullerene

The ability to detect protein biomarkers at a sub-nanomolar level represents a pervasive challenge in order to bring a significant improvement in early diagnosis or progression of pato-physiological processes. To this aim, Screen Printed Electrochemical Sensors have been acquiring a predominant importance. The possibility to use them with different measurement techniques, and to customize their surface to improve the performance represent really attractive features. In this work, performances of two different carbon nanostructures in combination with Stripping Voltammetry were evaluated as tools to improve the detection of Interleukin 8, a cytokine that has pivotal roles in various inflammatory processes and considered as a universal biomarker. Commercially-available Carbon sensors were modified using Carbon Nanotubes and Spherical Fullerene through drop casting technique. Interleukin 8 was quantified using an indirect techniques based on silver stripping catalyzed using Alkaline Phosphatase. The nanostructured sensors showed better sensitivity with sub-nanomolar limit of detection: 0.39 ng/ml for carbon nanotubes and 0.61 ng/ml for fullerene compared to bare carbon electrodes. These modification method is promising for sensitive detection of protein biomarkers in several applications, including the monitoring of inflammatory processes.

Carbon on poly(ε-caprolactone) (PCL) Ink-jet Printed Sensor for Monitoring Cell Cultures of Myoblasts

Nowadays techniques for sensitive non-invasive, real-time monitoring of cell differentiation and maturation are highly demanded. In light of this, the development of electrochemical printed sensors impedance-based could represent a promising tool. In the present work, we developed 2D ink-jet printed sensors for myoblasts adhesion monitoring, using carbon-based ink on a substrate consisting in non-woven electrospun mats made in crosslinked poly(e-caprolactone) (PCL). First of all, sensors printability was optimized and the biocompatibility tested. In order to determine the possibility to employ the prepared systems as scaffolds for dynamic cellular cultures, the mechanical response of the PCL scaffold was evaluated through the application of cyclic deformation tests. After that, electrical characterization of ink and substrate was performed, followed by electrochemical impedance-based measurements to evaluate myoblasts adhesion. Biocompatibility assessment showed good results for both carbon and PCL. Mechanical tests findings suggested that a training of 50 cycles and a proper value of strain should be applied before the cell seeding, in order to ensure a subsequent controlled strain amplitude. The sensorized scaffold allowed us to correlate cell adhesion with an increase of impedance module, in agreement with biocompatibility testing. Thus, this first preliminary testing suggested that this non-invasive impedance spectroscopy-based measurement system can be used for sensitive monitoring of cells adhesion, in static and moreover, as suggested from mechanical characterization, in dynamic conditions.

Wireless Point-of-Care Platform With Screen-Printed Sensors for Biomarkers Detection

Measurement systems for early and reliable detection of degenerative diseases, such as Alzheimer’s disease (AD), are extremely important in clinical diagnosis. Among these, biochemical assays represent a commonly used method to distinguish patients from healthy population thanks to the sensitive recognition of specific biomarkers in biological fluids. In order to overcome actual limitations of these techniques in term of cost, standardization, and sensitivity, this study aimed to realize a low-cost highly sensitive portable point-of-care (PoC) testing system based on screen-printed electrochemical sensors. The development of the platform specifically included both the design of the sensing probe and the electronic circuit devoted to condition and acquires the transduced electric signal. The designed circuit was implemented in a printed circuit board and interfaced to a wireless system based on bluetooth data transmission in order to improve the portability of the proposed solution. Preliminary results were obtained by using controlled concentrations of electrolytic solutions and calibrating the sensors for antibodies and for a well-known protein (i.e., interleukin 8) quantified by anodic stripping voltammetry (ASV). Findings from ASV measurements showed a sensitivity of

Preliminary study of a low-cost point-of-care testing system using screen-printed biosensors: For early biomarkers detection related to Alzheimer Disease

38~\mu \text{A}

Preliminary Study of Inkjet Printed Sensors for Monitoring Cell Cultures

/(ng/ml) with a tested range from 1.25 to 20 ng/ml, with a limit of detection of 2 ng/ml. Further investigation will include the validation of this PoC device by testing the concentration of a specific p53 protein isoform, which was recently identified to early correlate to AD development.