Bactericidal Effect of Lauric Acid-Loaded PCL-PEG-PCL Nano-Sized Micelles on Skin Commensal Propionibacterium acnes

Abstract

Abstract:Acne is the over growth of the commensal bacteria Propionibacterium acnes (P. acnes) on human skin. Lauric acid (LA) has been investigated as an effective candidate to suppress the activity of P. acnes. Although LA is nearly insoluble in water, dimethyl sulfoxide (DMSO) has been reported to effectively solubilize LA. However, the toxicity of DMSO can limit the use of LA on the skin. In this study, LA-loaded poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) micelles (PCL-PEG-PCL) were developed to improve the bactericidal effect of free LA on P. acnes. The block copolymers mPEG-PCL and PCL-PEG-PCL with different molecular weights were synthesized and characterized using 1 H Nuclear Magnetic Resonance spectroscopy ( 1 H NMR), Fourier-transform infrared spectroscopy (FT-IR), Gel Permeation Chromatography (GPC), and Differential Scanning Calorimetry (DSC). In the presence of LA, mPEG-PCL diblock copolymers did not self-assemble into nano-sized micelles. On the contrary, the average particle sizes of the PCL-PEG-PCL micelles ranged from 50-198 nm for blank micelles and 27-89 nm for LA-loaded micelles. The drug loading content increased as the molecular weight of PCL-PEG-PCL polymer increased. Additionally, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of free LA were 20 and 80 µg/mL, respectively. The MICs and MBCs of the micelles decreased to 10 and 40 µg/mL, respectively. This study demonstrated that the LA-loaded micelles are a potential treatment for acne.

Amphiphilic Block Copolymer PCL-PEG-PCL as Stationary Phase for Capillary Gas Chromatographic Separations

“…FT-IR and 1 H-NMR were used to confirm the structure of PCL-PEG-PCL which was in good agreement with the literature [26,29,30]. The FT-IR spectrum of PCL-PEG-PCL is displayed in Figure S1.…”

Antibacterial Free Fatty Acids and Monoglycerides: Biological Activities, Experimental Testing, and Therapeutic Applications

“…In an alternative strategy, LA was loaded into nano-sized micelles to evaluate its antibacterial efficacy and loading capacity [ 152 ]. Poly(caprolactone) poly (ethylene glycol)-poly(caprolactone) (PCL-PEG-PCL) micelles were developed as one promising option.…”

Lipid Nanoparticle Technology for Delivering Biologically Active Fatty Acids and Monoglycerides

“…Aside from membranous liposomal and bicellar nanostructures, there has been exploration of other types of nanostructure for encapsulating fatty acids and monoglycerides. Tran et al also reported the development of polymeric micelles composed of poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL) micelles and LA in a 5:1 mass ratio [ 51 ]. Depending on the PCL-PEG-PCL molecular weight, the LA-loaded polymeric micelles had ~30–90 nm diameters and exhibited approximately two-fold more potent antibacterial activity against P. acnes than free LA alone.…”