Opto-electronic feedback control of membrane potential for real-time control of action potentials.

To unlock new research possibilities by acquiring control of action potential (AP) morphologies in excitable cells, we developed an opto-electronic feedback loop-based system integrating cellular electrophysiology, real-time computing, and optogenetic approaches and applied it to monolayers of heart muscle cells. This allowed accurate restoration and preservation of cardiac AP morphologies in the presence of electrical perturbations of different origin in an unsupervised, self-regulatory manner, without any prior knowledge of the disturbance. Moreover, arbitrary AP waveforms could be enforced onto these cells.

Optoelectronic control of cardiac rhythm: Toward shock-free ambulatory cardioversion of atrial fibrillation.

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia, progressive in nature, and known to have a negative impact on mortality, morbidity, and quality of life. Patients requiring acute termination of AF to restore sinus rhythm are subjected to electrical cardioversion, which requires sedation and therefore hospitalization due to pain resulting from the electrical shocks. However, considering the progressive nature of AF and its detrimental effects, there is a clear need for acute out-of-hospital (i.

Light transmittance in human atrial tissue and transthoracic illumination in rats support translatability of optogenetic cardioversion of atrial fibrillation.

Background: Optogenetics could offer a solution to the current lack of an ambulatory method for the rapid automated cardioversion of atrial fibrillation (AF), but key translational aspects remain to be studied.

Objective: To investigate whether optogenetic cardioversion of AF is effective in the aged heart and whether sufficient light penetrates the human atrial wall.

Methods: Atria of adult and aged rats were optogenetically modified to express light-gated ion channels (i.

PDMS Curing Inhibition on 3D-Printed Molds: Why? Also, How to Avoid It?

Three-dimensional (3D)-printing techniques such as stereolithography (SLA) are currently gaining momentum for the production of miniaturized analytical devices and molds for soft lithography. However, most commercially available SLA resins inhibit polydimethylsiloxane (PDMS) curing, impeding reliable replication of the 3D-printed structures in this elastomeric material. Here, we report a systematic study, using 16 commercial resins, to identify a fast and straightforward treatment of 3D-printed structures and to support accurate PDMS replication using UV and/or thermal post-curing.