Centrifugally Spun Natural Fibers with Zinc Oxide Nanoparticles—A Novel Therapeutic Strategy for Acne Vulgaris

Acne vulgaris is a serious dermatological disease affecting a significant part of the population. Currently, available therapeutics are effective only at high concentrations, which has a negative environmental and economic impact. In particular, ZnO nanoparticles (NPs) have a great potential in various biomedical applications due to their specific properties and antibacterial/antiviral aktivity [1,2].

Electrospinning is a well-known technique for the nanofiber synthesis from a solution using high electrostatic field. However, this technique still has some shortcomings, such as a low production rate and requires a high voltage. Centrifugal spinning works only on centrifugal force, which is robust in terms of yield, and thus eliminates the above-mentioned shortcomings [3,4]. The fibers based on gums blended with other polymers can be shaped and modified according to the targeted application. Recently, new approaches to the use of polymeric fibers have also shown potential for cosmetic and dermatological applications. In general, different types of creams, hydrogels and films are often being limited by their application, e.g. due to easy contamination over time and prevention of skin ventilation [5]. In contrast, fibrous materials possess unique characteristics, including high porosity, a large specific surface area, and good breathability, making them ideal carriers for cosmetic and dermatologic application. Combining fibers with ZnO NPs creates a synergistic effect that holds great promise for the effective treatment of Acne vulgaris [6].

In this study, biomedically approved ZnO NPs with distinct diameter were used as the active therapeutic modality to treat acne-causing pathogens. For the first time, we show the utilization of ZnO NPs that were evenly distributed within centrifugally spun fiber carriers. Upon application on the skin, ZnO NPs can sustainably release and have profound antibacterial activity at lower therapeutic concentrations. Fibers were made using innovative centrifugal spinning procedure from natural polymers - gum arabic and pullulan - that are known for their biocompatibility. Different amount of ZnO NPs (from 0.03 to 4.5 wt.% related to the dry mass) was added into the spinning polymer solution, either in a form of a dry powder or as a dispersion containing NPs and isopropyl myristate. The resulting fibers were subsequently characterized for morphology and presence of ZnO NPs by Scanning Electron Microscopy and Energy-Dispersive X-ray fluorescence spectrometry. The materials were thoroughly assessed for their antibacterial activity against Cutibacterium acnes and Staphylococcus epidermidis, which are major opportunistic pathogens causing acne. The combination of two types of nanomaterials, namely active nanoparticles and fiber carriers, proved to be very promising and bear a great potential for the treatment of these diseases [6].

[1] R. Balkrishnan et al., Predictors of healthcare outcomes and costs related to medication use in patients with acne in the United States, Clin. Ther. 77(2006), 251–255.
[2] A. Sirelkhatim et al., Review on zinc oxide nanoparticles: Antibacterial activity and toxicity mechanism, Nano-Micro Lett. 7(2015), 219–242.
[3] M. Rihova et al., Water-born 3D nanofiber mats using cost-effective centrifugal spinning: comparison with electrospinning process: A complex study, J. Appl Polym Sci. 168 2021), e49975.
[4] S. Padron et al., Experimental study of nanofiber production through forcespinning, J. Appl. Phys., 113(2013), 024318.
[5] M. Rihova et al., The centrifugal spinning of vitamin doped natural gum fibers for skin regeneration, Carbohydr. Polym. 294(2022), 119792.
[6] M. Rihova et al., Biopolymeric fibers prepared by centrifugal spinning blended with ZnO nanoparticles for the treatment of Acne vulgaris, Appl. Mater. 37(2024), 102151.