Filter media and filters are provided that include at least two layers and a plurality of nanoparticles dispersed in depth within at least one of the layers. A gas filter comprises a first layer of fibers, a second layer of fibers bonded to the first layer and a plurality of nanoparticles incorporated into the first layer. The nanoparticles increase the overall surface area within the filter, which increases its filtration efficiency and allows for the capture of submicron contaminants without significantly compromising other factors, such as pressure drop (i.e., air flow) through the filter. In addition, the filters disclosed herein are capable of withstanding rigorous conditioning, which allows the filter to achieve the same level of filtration performance throughout the lifetime of the filter. Systems, devices and methods are also provided for manufacturing such filters.

A meltblown material formed from bicomponent fibers that can withstand the effects of a gamma irradiation sterilization process without negatively impacting bacterial filtration, particulate filtration, and/or breathability of personal protective equipment products formed from the meltblown material (e.g., facemasks, surgical gowns, surgical caps, etc.) is provided. The bicomponent fibers include a polyolefin-based sheath and a polyester-based core. Further, both the sheath and core include specific antioxidants and charge enhancer packages that allow for the effective electret treatment of the resulting meltblown material prior to sterilization, where the filtration efficiency and pressure differential of the material are still adequate post-sterilization.

A meltblown material formed from bicomponent fibers that can withstand the effects of a gamma irradiation sterilization process without negatively impacting bacterial filtration, particulate filtration, and/or breathability of personal protective equipment products formed from the meltblown material (e.g., facemasks, surgical gowns, surgical caps, etc.) is provided. The bicomponent fibers include a polyester-based sheath and a polyolefin-based core. Further, both the sheath and core include specific antioxidants and charge enhancer packages that allow for the effective electret treatment of the resulting meltblown material prior to sterilization, where the filtration efficiency and pressure differential of the material are still adequate post-sterilization.