This study ascertained the stability of phycobiliprotein (PBP), a bioactive protein from Dulse (Palmaria palmata) loaded within liposomes and stabilized with polyethylene glycol (2000 and 4000 g/mol) and desulfated CNCs (DCs) containing adsorbed polyethylene glycol (DCs-2000 and DCs-4000). The effect of pH, temperature and illumination on the stability of PBP was investigated. Results showed that the temperature had the most significant (p < 0.05) effect on the fluorescence intensity of the PBP, accounting for up to 70% loss of the fluorescence intensity for PBP loaded liposome (PL), PL stabilized with PEG-2000 (PLP-2000) and PEG 4000 (PLP-4000) and PL stabilized with desulfated CNCs (DCs), however, 60% for the PL stabilized with PEG 2000 and PEG 4000 adsorbed CNCs (PLDCs-2000 and PLDCs-4000) at 60 °C compared to those stabilized at 4 °C. A further increase in temperature to 80 °C led to a complete loss of fluorescence. Operating at the extreme pH's of 1.0 and 11.0 resulted in a loss of 90% and 30% fluorescence intensity, respectively for PBP in solution, whereas, 20% and 2% loss was observed for PBP incorporated inside the liposomes. Regarding the effect of illumination, PLDCs-2000 and PLDCs-4000 were the most stable, retaining the fluorescence intensity of PBP up to 70% after 72 h of exposure. This is compared to 85% loss of fluorescence for PBP in solution. Furthermore, at pH of 1.0, there was an increase in average particle size for the PLDCs-2000 and PLDCs-4000 from 189 ± 3 & 206 ± 2 nm to 6464 ± 211 & 6698 ± 317 nm and a charge reversal in the zeta potential from −36 ± 1 & −34 ± 2 to +16 ± 3 & +14 ± 1. Confocal and optical microscopic images confirmed the coalescence of PBP loaded liposome and agglomeration PLDCs-2000 and PLDCs-4000 under acidic pH (<3.0). In contrast, changes in temperature from 4 °C to 100 °C and illumination as a function of time up to 72 h resulted in no change in liposome size and zeta potential.

这项研究确定了藻胆蛋白（PBP）的稳定性，藻胆蛋白（Dulse（Palaria palmata））装入脂质体中，并用聚乙二醇（2000和4000 g / mol）和含有吸附的聚乙二醇的脱硫CNCs（DCs）（DCs-2000和DCs-4000）稳定。研究了pH，温度和光照对PBP稳定性的影响。结果表明，温度对PBP的荧光强度影响最大（p <0.05），占装载PBP的脂质体（PL）的荧光强度损失高达70％，用PEG-2000（PLP）稳定的PL -2000）和PEG 4000（PLP-4000）和PL用脱硫的CNCs（DCs）稳定，但是，在60°C下用PEG 2000和PEG 4000吸附的CNCs（PLDCs-2000和PLDCs-4000）稳定的PL的60％与稳定在4°C的相比。温度进一步升高至80°C导致荧光完全消失。在极限pH下运行 1.0和11.0的s分别导致溶液中PBP的荧光强度损失90％和30％，而掺入脂质体内部的PBP观察到20％和2％的荧光强度损失。关于照明的效果，PLDCs-2000和PLDCs-4000是最稳定的，在暴露72 h后，PBP的荧光强度保持高达70％。相比之下，溶液中PBP的荧光损失为85％。此外，在pH值为1.0时，PLDCs-2000和PLDCs-4000的平均粒径从189±3＆206±2 nm增加到6464±211＆6698±317 nm，并且zeta电位反转从-36±1和-34±2到+16±3和+14±1。共聚焦和光学显微图像证实了在酸性pH值（<3.0）下装载PBP的脂质体和聚结PLDCs-2000和PLDCs-4000的聚结。