破膜乳酸酯是一类重要的表面活性剂分子,是脂肪酸和乳酸的酯化加合物,具有工业上有吸引力的特性。如高抗菌效力和亲水性。与游离脂肪酸和甘油单酯等抗菌脂质相比,从生物物理的角度来看,几乎没有研究乳酸酯的膜破坏特性,解决这一差距对于建立对乳酸酯工作原理的分子水平理解非常重要。在这里,使用石英晶体微天平耗散(QCM-D)和电化学阻抗谱(EIS)技术,我们实时调查,月桂酰乳酸钠(SLL)之间的膜破坏性相互作用-一种有希望的12碳长的乳酸,饱和烃链和支持的脂双层(SLB)和束缚双层脂质膜(tBLM)平台。为了比较,可能在生物环境中产生的SLL的水解产物,即,月桂酸(LA)和乳酸(LacA),还单独和作为混合物进行了测试,以及结构相关的表面活性剂(十二烷基硫酸钠,SDS).而SLL,洛杉矶,和SDS都具有相同的链性质和临界胶束浓度(CMC)值,我们的研究结果表明,SLL表现出明显的膜破坏特性,SDS的完全溶解活性和LA的更适度的破坏特性。有趣的是,SLL的水解产物,即,LA+LacA混合物,诱发了更大程度的瞬态,可逆的膜形态变化,但最终比SLL更少的永久性膜破坏。这些分子水平的见解支持,仔细调整抗菌脂质头基特性可以调节膜破坏性相互作用的光谱,提供了一种设计具有定制生物降解特性的表面活性剂的途径,并增强了SLL作为破坏膜的抗微生物药物候选物具有有吸引力的生物物理优点。
Membrane-disrupting lactylates are an important class of surfactant molecules that are esterified adducts of fatty acid and lactic acid and possess industrially attractive properties, such as high antimicrobial potency and hydrophilicity. Compared with antimicrobial lipids such as free fatty acids and monoglycerides, the membrane-disruptive properties of lactylates have been scarcely investigated from a biophysical perspective, and addressing this gap is important to build a molecular-level understanding of how lactylates work. Herein, using the quartz crystal microbalance-dissipation (QCM-D) and electrochemical impedance spectroscopy (EIS) techniques, we investigated the real-time, membrane-disruptive interactions between sodium lauroyl lactylate (SLL)-a promising lactylate with a 12-carbon-long, saturated hydrocarbon chain-and supported lipid bilayer (SLB) and tethered bilayer lipid membrane (tBLM) platforms. For comparison, hydrolytic products of SLL that may be generated in biological environments, i.e., lauric acid (LA) and lactic acid (LacA), were also tested individually and as a mixture, along with a structurally related surfactant (sodium dodecyl sulfate, SDS). While SLL, LA, and SDS all had equivalent chain properties and critical micelle concentration (CMC) values, our findings reveal that SLL exhibits distinct membrane-disruptive properties that lie in between the rapid, complete solubilizing activity of SDS and the more modest disruptive properties of LA. Interestingly, the hydrolytic products of SLL, i.e., the LA + LacA mixture, induced a greater degree of transient, reversible membrane morphological changes but ultimately less permanent membrane disruption than SLL. These molecular-level insights support that careful tuning of antimicrobial lipid headgroup properties can modulate the spectrum of membrane-disruptive interactions, offering a pathway to design surfactants with tailored biodegradation profiles and reinforcing that SLL has attractive biophysical merits as a membrane-disrupting antimicrobial drug candidate.