Rieth Monica D, Lozano Andrew
Department of Chemistry, Southern Illinois University Edwardsville, 44 South Circle Drive, Box 1652, Science West, Edwardsville, IL, 62026, USA.
Biochem Biophys Rep. 2020 Apr 20;22:100764. doi: 10.1016/j.bbrep.2020.100764. eCollection 2020 Jul.
Liposomes are an important tool and have gained much attention for their promise as an effective means of delivering small therapeutic compounds to targeted sites. In an effort to establish an effective method to produce liposomes from the lipid, dipalmitoyl-phosphatidylcholine or DPPC, we have found important aspects that must be taken into consideration. Here, we used probe-tip sonication to prepare liposomes on a batch scale. During this process we uncovered interesting steps in their preparation that altered the thermodynamic properties and phase transitions of the resulting liposome mixtures. Using differential scanning calorimetry to assess this we found that increasing the sonication time had the most dramatic effect on our sample, producing almost an entirely separate phase transition relative to the main phase transition. This result is consistent with reports from the current literature. We also highlight a smaller transition, which we attribute to traces of unincorporated lipid that seems to gradually disappear as the total lipid concentration decreases. Overall, sonication is an effective means of producing liposomes, but we cannot assert this method is optimal in producing them with precise physical properties. Here we highlight the physical effects at play during this process.
脂质体是一种重要的工具，因其有望成为将小治疗性化合物递送至靶向部位的有效手段而备受关注。为了建立一种从脂质二棕榈酰磷脂酰胆碱（DPPC）制备脂质体的有效方法，我们发现了一些必须考虑的重要方面。在此，我们使用探头超声在批量规模上制备脂质体。在此过程中，我们发现了其制备过程中有趣的步骤，这些步骤改变了所得脂质体混合物的热力学性质和相变。使用差示扫描量热法对此进行评估，我们发现增加超声处理时间对我们的样品影响最为显著，相对于主要相变产生了几乎完全独立的相变。这一结果与当前文献报道一致。我们还突出了一个较小的转变，我们将其归因于未掺入脂质的痕迹，随着总脂质浓度降低，这些痕迹似乎逐渐消失。总体而言，超声处理是制备脂质体的有效手段，但我们不能断言这种方法在制备具有精确物理性质的脂质体方面是最优的。在此我们突出了此过程中起作用的物理效应。
