BEGIN:VCALENDAR VERSION:2.0 PRODID:-//wp-events-plugin.com//6.6.4.4//EN TZID:Asia/Jerusalem X-WR-TIMEZONE:Asia/Jerusalem BEGIN:VEVENT UID:1143@biotech.technion.ac.il DTSTART;TZID=Asia/Jerusalem:20260204T140000 DTEND;TZID=Asia/Jerusalem:20260204T150000 DTSTAMP:20260203T115759Z URL:https://biotech.technion.ac.il/events/special-guest-seminar-dr-ran-tiv ony-department-of-chemical-engineering-ben-gurion-university-of-the-negev/ SUMMARY:Special Guest Seminar: Dr. Ran Tivony\, Department of Chemical Engi neering\, Ben-Gurion University of the Negev DESCRIPTION:Quantifying Ion Transport and Electrochemical Gradients in Synt hetic Cell Membranes\nDepartment of Chemical Engineering\nBen-Gurion Unive rsity of the Negev\, Israel\n **Lecture will be given in English**\n  \;\nAbstract:\nLiving cells rely on the controlled movement of ions across their membranes to produce and store energy. In cellular membranes\, ion fluxes generate electrochemical potential gradients that power essential p rocesses such as ATP synthesis\, nutrient uptake\, and membrane potential maintenance. Reproducing these fundamental functions in synthetic membrane systems such as giant unilamellar vesicles (GUVs)\, micron-sized liposome s\, is an important goal toward achieving artificial cells with life-like functionalities. However\, achieving this objective remains challenging du e to the lack of quantitative\, single-compartment methods to measure ion fluxes and electrochemical gradient formation in such synthetic cell-like systems. Here\, we present a fluorescence-based approach for quantifying i on fluxes and the resulting changes in electrochemical potential gradients across the membranes of individual GUVs. To achieve precise control over vesicle size and membrane composition\, we developed an integrated microfl uidic platform enabling high-throughput production and purification of mon odisperse GUVs. By combining this platform with quantitative fluorescence analysis\, we determined the permeation rates of two biologically importan t ions – protons (H⁺) and potassium (K⁺) – and directly correlated their fluxes with electrochemical gradient accumulation across the lipid bilayer of single vesicles. Using the same analytical framework\, we quant ified the ion selectivity of two archetypal ion channels\, gramicidin A an d outer membrane porin F (OmpF)\, by measuring the permeation rates of H ⁺ and K⁺. We found that proton translocation through gramicidin A is f our orders of magnitude faster than potassium transport\, whereas OmpF exh ibits comparable permeation rates for both ions. We expect that this quant itative approach can inform the design of GUV-based synthetic cells with m ore complex transport features and provide a versatile platform for explor ing ion transport processes relevant to living cells.\n ATTACH;FMTTYPE=image/jpeg:https://biotech.technion.ac.il/wp-content/upload s/2026/02/דר-רן-טבעוני-scaled.jpg CATEGORIES:סמינרים END:VEVENT BEGIN:VTIMEZONE TZID:Asia/Jerusalem X-LIC-LOCATION:Asia/Jerusalem BEGIN:STANDARD DTSTART:20251026T010000 TZOFFSETFROM:+0300 TZOFFSETTO:+0200 TZNAME:IST END:STANDARD END:VTIMEZONE END:VCALENDAR