Referenceless pH Sensor using Organic Electrochemical Transistors

pH is an extremely important parameter in all biological and most chemical reactions. pH sensing has been specifically shown to be of paramount importance in many fields such as environmental science, sport, or healthcare as the acidosis or alkalinity of a solution is a marker of a physiological state. Indeed, pH variation can be indicative of lactate production during infection.[1] Besides, during intensive training, the con-centration of lactic acid in sweat increases,[2] decreasing by this way the pH of the sweat. The normal body pH value is different for each subject, which is why, in most cases, we want to detect variations of pH rather than its absolute value

Referenceless pH Sensor using Organic Electrochemical Transistors

International audienceUsing printing techniques, organic electrochemical transistors are integrated in a differential bridge. This circuit allows biochemical sensing without the use of a reference electrode. Electrodeposited iridium oxide gate electrodes enable pH measurements with increased sensitivity, also demonstrated in complex biological media such as human sweat

Fully printed metabolite sensor using organic electrochemical transistor

As conducting polymer based devices, organic electrochemical transistors (OECTs) are suited for printing process. The convenience of the screen-printing techniques allowed us to design and fabricate OECTs with a selected design and using different gate material. Depending on the material used, we were able to tune the transistor for different biological application. Ag/AgCl gate provided transistor with good transconductance, and electrochemical sensitivity to pH was provided by polyaniline ink. Finally, we validate the enzymatic sensing of glucose and lactate with a Poly(3,4-ethylene dioxythiophene) doped with poly(styrene sulfonate) (PEDOT:PSS) gate often used due to its biocompatible properties. The screen-printing process allowed us to fabricate a large amount of devices in a short period of time, using only commercially available grades of ink, showing by this way the possible transfer to industrial purpose

On the Influence of Fin Corner Rounding in 3D Nanocrystal Flash Memories.

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Screen-printed organic electrochemical transistors for metabolite sensing

Screen-printed organic electrochemical transistors (OECTs) were tested as glucose and lactate sensors. The intrinsic amplification of the device allowed it to detect metabolites in low molecular range and validation tests were made on real human sweat. The development of an organically modified sol-gel solid electrolyte paves the way for all printed OECT-based biosensors

On the Influence of Fin Corner Rounding in 3D Nanocrystal Flash Memories.

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Loss of Sip1 leads to migration defects and retention of ectodermal markers during lens development

SIP1 encodes a DNA-binding transcription factor that regulates multiple developmental processes, as highlighted by the pleiotropic defects observed in Mowat-Wilson syndrome, which results from mutations in this gene. Further, in adults, dysregulated SIP1 expression has been implicated in both cancer and fibrotic diseases, where it functionally links TGFβ signaling to the loss of epithelial cell characteristics and gene expression. In the ocular lens, an epithelial tissue important for vision, Sip1 is co-expressed with epithelial markers, such as E-cadherin, and is required for the complete separation of the lens vesicle from the head ectoderm during early ocular morphogenesis. However, the function of Sip1 after early lens morphogenesis is still unknown. Here, we conditionally deleted Sip1 from the developing mouse lens shortly after lens vesicle closure, leading to defects in coordinated fiber cell tip migration, defective suture formation, and cataract. Interestingly, RNA-Sequencing analysis on Sip1 knockout lenses identified 190 differentially expressed genes, all of which are distinct from previously described Sip1 target genes. Furthermore, 34% of the genes with increased expression in the Sip1 knockout lenses are normally downregulated as the lens transitions from the lens vesicle to early lens, while 49% of the genes with decreased expression in the Sip1 knockout lenses are normally upregulated during early lens development. Overall, these data imply that Sip1 plays a major role in reprogramming the lens vesicle away from a surface ectoderm cell fate towards that necessary for the development of a transparent lens and demonstrate that Sip1 regulates distinctly different sets of genes in different cellular contexts

Novel low temperature 3D wafer stacking technology for high density device integration

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