Domingues Joana M, Teixeira Marta O, Teixeira Marta A, Freitas David, Silva Samira F da, Tohidi Shafagh D, Fernandes Rui D V, Padrão Jorge, Zille Andrea, Silva Carla, Antunes Joana C, Felgueiras Helena P
Centre for Textile Science and Technology (2C2T), Campus de Azurém, University of Minho, 4800-058 Guimaraes, Portugal.
Centre of Biological Engineering (CEB), Campus de Gualtar, University of Minho, 4710-057 Braga, Portugal.
Pharmaceutics. 2022 Jan 27;14(2):303. doi: 10.3390/pharmaceutics14020303.
One of the most important measures implemented to reduce SARS-CoV-2 transmission has been the use of face masks. Yet, most mask options available in the market display a passive action against the virus, not actively compromising its viability. Here, we propose to overcome this limitation by incorporating antiviral essential oils (EOs) within polycaprolactone (PCL) electrospun fibrous mats to be used as intermediate layers in individual protection masks. Twenty EOs selected based on their antimicrobial nature were examined for the first time against the MS2 virus (potential surrogate of SARS-CoV-2). The most effective were the lemongrass (LGO), Niaouli (NO) and eucalyptus (ELO) with a virucidal concentration (VC) of 356.0, 365.2 and 586.0 mg/mL, respectively. PCL was processed via electrospinning, generating uniform, beadless fibrous mats. EOs loading was accomplished via two ways: (1) physisorption on pre-existing mats (PCLaEOs), and (2) EOs blending with the polymer solution prior to fiber electrospinning (PCLbEOs). In both cases, 10% / VC was used as loading concentration, so the mats' stickiness and overwhelming smell could be prevented. The EOs presence and release from the mats were confirmed by UV-visible spectroscopy (≈5257-631 µg) and gas chromatography-mass spectrometry evaluations (average of ≈14.3% EOs release over 4 h), respectively. PCLbEOs mats were considered the more mechanically and thermally resilient, with LGO promoting the strongest bonds with PCL (PCLbLGO). On the other hand, PCLaNO and PCLaELO were deemed the least cohesive combinations. Mats modified with the EOs were all identified as superhydrophobic, capable of preventing droplet penetration. Air and water-vapor permeabilities were affected by the mats' porosity (PCL < PCLaEOs < PCLbEOs), exhibiting a similar tendency of increasing with the increase of porosity. Antimicrobial testing revealed the mats' ability to retain the virus (preventing infiltration) and to inhibit its action (log reduction averaging 1). The most effective combination against the MS2 viral particles was the PCLbLGO. These mats' scent was also regarded as the most pleasant during sensory evaluation. Overall, data demonstrated the potential of these EOs-loaded PCL fibrous mats to work as COVID-19 active barriers for individual protection masks.
为减少新冠病毒传播而采取的最重要措施之一是使用口罩。然而，市场上大多数口罩对病毒的防护作用是被动的，无法有效降低其活性。在此，我们建议通过将抗病毒精油（EOs）掺入聚己内酯（PCL）电纺纤维垫中，用作个人防护口罩的中间层，以克服这一局限性。基于其抗菌特性挑选出的20种精油首次用于检测对MS2病毒（新冠病毒的潜在替代物）的效果。最有效的是柠檬草精油（LGO）、绿花白千层精油（NO）和桉叶油（ELO），其杀病毒浓度（VC）分别为356.0、365.2和586.0毫克/毫升。PCL通过静电纺丝加工，制成均匀、无珠的纤维垫。精油的负载通过两种方式实现：（1）在预先制备的纤维垫上进行物理吸附（PCLaEOs），以及（2）在纤维静电纺丝前将精油与聚合物溶液混合（PCLbEOs）。在这两种情况下，均使用10%/VC作为负载浓度，以防止纤维垫发粘和气味过重。分别通过紫外可见光谱（约5257 - 631微克）和气相色谱 - 质谱评估（4小时内平均约14.3%的精油释放）确认了纤维垫中精油的存在和释放。PCLbEOs纤维垫被认为在机械性能和热稳定性方面更具弹性，其中LGO与PCL形成的键最强（PCLbLGO）。另一方面，PCLaNO和PCLaELO被认为是内聚力最小的组合。用精油改性的纤维垫均被鉴定为超疏水，能够防止液滴渗透。空气和水蒸气渗透率受纤维垫孔隙率的影响（PCL < PCLaEOs < PCLbEOs），呈现出随孔隙率增加而增加的类似趋势。抗菌测试表明，纤维垫具有截留病毒（防止渗透）和抑制其作用（平均对数减少1）的能力。对MS2病毒颗粒最有效的组合是PCLbLGO。在感官评价中，这些纤维垫的气味也被认为是最宜人的。总体而言，数据表明这些负载精油的PCL纤维垫有潜力作为新冠病毒的活性屏障用于个人防护口罩。
