Membrane Dynamics: Fluorescence Spectroscopy

Abstract

Membranes are dynamic lipophilic structures that constitute a selective barrier essential for the smooth functioning of cellular machinery. Their complex and highly heterogeneous composition, as well as the intricate diffusion patterns that they display, have been intensely studied in the past decades. Several innovative microscopy techniques have recently been developed to gain insight into the basis of membrane dynamics, interactions, and molecular organization. In this article, we introduce four pioneer fluorescence‐based approaches that have substantially broadened our overall understanding of membranes: fluorescence correlation spectroscopy (FCS), single particle tracking (SPT), fluorescence recovery after photobleaching (FRAP), and 6‐lauroyl‐2‐(dimethylamino)‐naphtalene (LAURDAN) microscopy. We discuss each technique in detail, explaining their principles, methodology, and applications in the research of the dynamic processes controlled by membranes.

Transparent Nanopore Cavity Arrays Enable Highly Parallelized Optical Studies of Single Membrane Proteins on Chip

“…The normalized fluorescence intensity ( I t ) was calculated according eq in which I o is the initial fluorescence, I inf is the fluorescence intensity after recovery, and τ 1/2 is the time at half-maximal fluorescence intensity. The lateral lipid diffusion coefficient ( D ) was determined regarding eq − with r o as the radius of the excitation spot and γ as the bleaching parameter …”

“…with r o as the radius of the excitation spot and γ as the bleaching parameter. 47 Single-Transporter Recordings. Ten micromolar of ATTO655 (0.6 kDa) and 5 μM of OG dextran (10 kDa) were encapsulated via liposome spreading.…”