The influence of NBD fluorescent probe on model membranes containing POPC and DPPC

Figures & data

Figure 1. Structure of fluorescent probe (A) NBD-DOPE; (B) C₆-NBD-PC.

Figure 2. Fluorescence images as a function of temperature for GUVs of (A) 30:70 POPC/DPPC; (B) 50:50 POPC/DPPC; (C) 70:30 POPC/DPPC. Each sample contains 1 mol% NBD-DOPE.

Figure 3. ²H NMR spectra of 50:50 POPC/DPPC-d31 and 50:50 POPC-d31/DPPC at (A) 17 °C; (B) 33 °C.

Figure 4. Fluorescence image as a function of temperature for GUVs of (A) 30:70 POPC/DPPC; (B) 50:50 POPC/DPPC; (C) 70:30 POPC/DPPC. Each sample contains 1 mol% C₆-NBD-PC.

Table 1. A comparison for T_mis,1 of NBD-DOPE-containing GUVs, T_mis,2 of NBD-DOPE-containing GUVs, and T_end measured without the fluorescent probe. Considering that the transition temperature was reduced by 2 °C due to the lipid chain deuteration, the transition temperature for non-deuteraturated lipid bilayers should be shifted by +2 °C.

	with NBD-DOPE	with C6-NBD-PC	without fluorescent probe
POPC/DPPC	Tmis,1 (°C)	Tmis,2 (°C)	Tend + 2 (°C)
30:70	34 ± 1	30 ± 1
50:50	30 ± 1	28 ± 1	35
70:30	27 ± 1	27 ± 1