Multi-stage nasal filter
Intra-nasal filter devices and methods for their manufacture and use are disclosed. An intra-nasal filter device includes: a first stage filter proximate the septum; and a second stage filter comprising a flexible material extending upwardly from the first filter stage filter; wherein the flexible material comprises: an impedance in the range of 0.02 to 0.2 cmH 2 O; an effective cross-sectional area in the range of 0.2 to 2 square inches; and a plurality of radially extending geometric structures disposed along an axial length of the second stage.
1. An intra-nasal filter device for use in a nasal cavity having an internal circumference extending from a proximal region proximate the sinus to a distal region proximate the septum, the device comprising:
a first filter stage to be positioned proximate the septum; and
a second stage comprising a filter material extending proximally from the first filter stage;
wherein the filter material as incorporated into the second stage exhibits an impedance in the range of 0.02 to 0.2 cmH 2 O, and aggregate surface area in the range of 0.5 to 2 square inches; and
wherein the second filter stage comprises longitudinal ribs twisted to form a closed tapered helical structure.
2. The device of claim 1 , wherein the second filter stage further comprises micro-features.
3. The device of claim 2 , wherein the micro-features comprise a regular repeating pattern of undulations.
4. The device of claim 1 , wherein the filter material comprises nanofibers.
5. The device of claim 1 wherein the filter material comprises an electrospun material.
6. The device of claim 1 , wherein the filter material as incorporated into the second stage exhibits impedance in the range of 0.05 to 0.1 cmH 2 O, and the aggregate surface area is in the range of 0.5 to 1 square inches.
7. The device of claim 1 , further comprising a resiliently deformable outer component configured to swab the distal region of the nostril interior with a disinfectant during device installation.
8. The device of claim 1 further comprising a spring element configured to urge the distal portion of the second stage outwardly to form a perimeter seal with the inside of the nostril.
9. The device of claim 1 further comprising a third filter stage comprising a flexible sheet loosely enveloping at least a portion of the second stage and forming an air gap therebetween.
10. The device of claim 1 wherein the filter material exhibits electrostatic properties.
11. The device of claim 1 wherein:
the first stage is characterized by a first MPPS1 value; and
the second stage is characterized by a second MPPS2 value.
12. The device of claim 1 wherein the material is characterized by two different values MPPS1 and MPPS1.2.
13. The device of claim 1 wherein the material is characterized by a most penetrating particle size (MPPS1) value of about 0.125 micrometers (urn).
14. An intra-nasal filter device comprising:
a first stage filter proximate the septum; and
a second stage filter comprising a flexible material extending upwardly from the first filter stage filter;
wherein the second stage filter comprises longitudinal ribs twisted to form a closed tapered helical structure and has:
an impedance value, as incorporated into the second stage filter, in the range of 0.02 to 0.2 cmH 2 O;
an aggregate surface area in the range of 0.5 to 2 square inches.
15. The device of claim 14 , wherein the flexible material comprises electrospun nanofibers exhibiting electrostatic and disinfectant properties.