What Are Nanofibers?

Nanofibers are fibers with diameters typically under 1,000 nanometers, roughly 50 to 2,000 times thinner than a human hair, produced from natural or synthetic polymers, or blends of both.^[1] At that scale, fibers pick up properties bulk materials simply don't have: an extremely high surface-area-to-volume ratio, tunable porosity, and, depending on the material, the ability to mimic biological structures like the extracellular matrix that human tissue grows on. That combination is why nanofibers show up in products as different as water filters, wound dressings, and N95-style respirator masks.

What Are Electrospun Nanofibers, Exactly?

A human hair is roughly 80,000–100,000 nanometers in diameter. Nanofibers, by most technical definitions, are fibers with at least one dimension below 1,000 nanometers, and in the highest-performance applications, diameters often run from the tens of nanometers up to a few hundred.^[1][2] That's small enough that a single gram of nanofiber material can carry an enormous amount of surface area, which is the property manufacturers are usually paying for: more surface area means more contact points for filtration, drug release, cell attachment, or chemical reaction, depending on the application.

Nanofibers can be solid, porous, or hollow, and can be spun as single-component fibers or as composite fibers that combine a base polymer with functional additives, like the boron nitride and silica used in TruSpin's polyceramic water filtration membranes, to add capabilities the base polymer doesn't have on its own.

It's worth being precise about terminology here, because it comes up in supplier conversations: "nanofiber" refers specifically to the fiber's diameter, not its length, composition, or manufacturing method. A nanofiber can be a few millimeters long or effectively continuous, made from dozens of different base materials, and produced by several different methods, electrospinning included. What makes it a nanofiber, rather than a microfiber or conventional fiber, is that sub-1,000-nanometer cross-section.

Nanofiber Size, in Context

What Are Nanofibers Made Of?

Nanofibers are generally grouped into two material families, which are frequently blended together:

Natural Polymers

Natural polymers, valued for biocompatibility and biodegradability:

• Collagen and gelatin
• Chitosan (from chitin, found in shellfish exoskeletons)
• Silk fibroin
• Cellulose

Synthetic Polymers

Synthetic polymers, valued for mechanical strength and processing consistency:

• Poly(lactic acid), PLA
• Polycaprolactone, PCL
• Polyurethane, PU
• Poly(lactic-co-glycolic acid), PLGA

Natural polymers like collagen and chitosan are common in biomedical nanofibers because they closely mimic the body's own tissue structures, but pure natural-polymer fibers are often mechanically weak, so they're frequently cross-linked or blended with synthetic polymers or with each other to balance biological performance with physical durability.^[3] Beyond these two families, some nanofibers incorporate inorganic or ceramic components, ranging from carbon nanofibers used in energy and electronics applications to the functional ceramic additives used in advanced filtration membranes.

Natural vs. Synthetic Nanofiber Materials

How Are Nanofibers Made?

The dominant commercial method for producing nanofibers is electrospinning, a process that uses an electric field, rather than heat or mechanical force, to draw a polymer solution into fiber. We cover the full mechanics of how that process works, and the meaningful differences between conventional (DC) and TruSpin's proprietary (AC) electrospinning methods, in a dedicated guide: What Is Electrospinning?

Electrospinning isn't the only nanofiber production method, but it's the one that dominates commercial and research use because it works across the widest range of polymers and gives the most control over final fiber diameter.^[1] Other methods exist for specific cases: melt blowing (used for larger-scale, lower-precision nonwoven fibers, common in standard air filter media), phase separation (used mostly at lab scale for certain biomedical scaffolds), and template synthesis or self-assembly (used for specialty applications requiring very specific fiber architecture). None of these alternative methods matches electrospinning's combination of fiber-diameter control, material versatility, and commercial scalability, which is why it remains the primary method behind most nanofiber products on the market today, including TruSpin's.

In short: the method used to produce a nanofiber has a direct effect on its consistency, defect rate, and the maximum volume a supplier can realistically produce, which matters as much to a purchasing decision as the fiber material itself.

What Can Electrospun Nanofiber Be Used For?

Because nanofiber properties can be tuned by material, diameter, and additive, the same underlying technology serves a wide range of industries:

• Water and air filtration — high surface area captures fine particulates and contaminants, including PFAS, that conventional filter media miss
• Biomedical and pharmaceutical — scaffolds that mimic the extracellular matrix for tissue engineering, wound healing, and controlled drug delivery
• Performance textiles — breathable, lightweight coatings for waterproofing, thermal regulation, and antimicrobial surfaces
• EMI shielding — lightweight, thin-profile conductive composites for electronics and aerospace
• Cosmetics and skincare — sheet masks and controlled-release delivery formats
• Thermal insulation — high thermal resistance in an ultra-thin profile
• Energy storage — battery separators and emerging solar cell components

See our full breakdown by industry, with examples of each, on the nanofiber applications page.

Are Nanofibers Safe?

This depends heavily on the form of the nanofiber and how it's encountered, and it's an area where the research is still developing. Engineered nanofiber products, filtration membranes, wound dressings, structural textiles, are bonded into a nonwoven mat or membrane, not loose airborne particles, and that physical form matters for safety. Nanotoxicology research to date has generally focused on inhalation exposure to loose, unbound nanoscale fibers rather than fibers that are fixed within a finished product. One 2026 inhalation study on cellulose nanofibers found measurable lung effects at higher airborne concentrations in animal testing, with a no-observed-adverse-effect level identified below 1.5 mg/m³, while a separate 28-day oral exposure study found no significant toxic effects.^[4][5] Separately, researchers evaluating nanofiber-based respiratory mask filters have noted that safety testing standards specific to nanofiber materials are still catching up to how quickly the technology is being adopted commercially.^[6]

The practical takeaway: nanofiber safety is form- and application-specific, not a single yes-or-no answer, and it's a reasonable question to ask any nanofiber supplier, along with what testing or certifications back their specific product. For buyers evaluating nanofiber materials for filtration, biomedical, or consumer-facing products, the more useful question usually isn't "are nanofibers safe" in the abstract, it's "what safety and biocompatibility testing has been done on this specific fiber, in this specific form, for this specific application." A credible supplier should be able to answer that directly.