UV-Irradiation Hypodermic Needle System

Technical Design Specifications

Executive Summary

This document describes a conceptual medical device design for an intravenous ultraviolet light delivery system. The device combines a hypodermic needle with an integrated fiber optic cable to deliver 222 nm far-UVC light directly into the bloodstream for potential antimicrobial/antiviral applications.

Note: This is a conceptual design for research purposes. Any actual implementation would require extensive biomedical engineering validation, FDA approval, and clinical trials.

1. System Overview

1.1 Design Philosophy

• Wavelength Selection: 222 nm far-UVC light (safer spectrum based on current research)

• Delivery Method: Fiber optic transmission through hypodermic needle lumen

• Target Application: Intravenous blood irradiation for potential viral load reduction

• Safety Approach: Multiple redundant safety systems and controlled dosimetry

1.2 Key Components

1. 222 nm Far-UVC LED light source

2. Fiber optic cable assembly

3. Modified hypodermic needle with integrated light diffuser

4. Safety control unit with dosimetry monitoring

5. Sterile connector hub assembly

2. Detailed Component Specifications

2.1 UV Light Source

Type: Far-UVC LED Module

• Peak Wavelength: 222 ±2 nm

• Spectral Bandwidth: <10 nm FWHM

• Output Power: 15 mW (adjustable 5-15 mW range)

• Power Supply: 12V DC, medical-grade isolated power supply

• Cooling: Passive heatsink with thermal monitoring

• Lifespan: >10,000 hours rated operation

• Safety Features:

  • Automatic shutoff if temperature exceeds 45°C

  • Current limiting circuitry

  • Emission indicator LED (visible spectrum)

Alternative Light Sources:

• KrCl excimer lamp (222 nm peak)

• Filtered mercury lamp with 222 nm bandpass filter

• Solid-state UV-C LED array

2.2 Fiber Optic Cable Assembly

Core Material: Fused silica (high UV transmission)

• Core Diameter: 200 μm

• Numerical Aperture: 0.22

• UV Transmission: >70% at 222 nm

• Length: 50-100 cm (clinical flexibility)

• Bend Radius: Minimum 15 mm

Cladding: Fluorinated polymer

• Thickness: 25 μm

• Function: Total internal reflection containment

Protective Buffer Coating: Medical-grade polymer

• Outer Diameter: 500 μm total

• Properties: Flexible, biocompatible, sterilizable

Connectors:

• Proximal End: SMA-905 connector to LED source

• Distal End: Custom sterile medical connector to needle hub

• Coupling Efficiency: >85%

2.3 Hypodermic Needle Assembly

Needle Specifications:

• Gauge: 21G (0.8 mm outer diameter)

• Wall Thickness: 0.15 mm

• Inner Diameter: 0.5 mm (accommodates 500 μm fiber)

• Length Options: 25 mm, 38 mm, 50 mm

• Material: Medical-grade stainless steel 316L

• Surface Finish: Electropolished, siliconized

• Bevel Type: Regular bevel (12° angle)

Fiber Integration:

• Fiber optic cable runs concentrically through needle lumen

• Secured at hub with medical-grade adhesive

• Allows minimal blood flow around fiber (annular space ≈0.025 mm)

2.4 Light Diffuser Tip

Design: Specialized micro-patterned quartz glass tip

• Position: Integrated at needle distal end

• Diameter: 0.45 mm (fits within needle lumen)

• Length: 3 mm

• Material: UV-grade fused quartz

Optical Properties:

• Diffusion Pattern: 360° radial emission

• Scattering Structures: Micro-etched surface patterns (5-10 μm features)

• Uniformity: ±15% intensity variation

• Transmission Efficiency: >80%

Light Distribution:

• Creates cylindrical irradiation zone around needle tip

• Effective irradiation radius: 2-5 mm in blood

• Uniform fluence distribution for consistent dosing

2.5 Connector Hub Assembly

Hub Material: Medical-grade polypropylene

• Design: Luer-lock compatible

• Features:

  • Internal fiber alignment guides

  • Strain relief for fiber optic cable

  • Transparent inspection window

  • Sterile barrier seal

Safety Locking Mechanism:

• Prevents accidental disconnection during treatment

• Audible/tactile click confirmation

• Color-coded for proper orientation

2.6 Protective Housing Unit

Enclosure: Medical-grade ABS plastic

• Dimensions: 120 mm × 60 mm × 40 mm

• Weight: <200 g

• Ingress Protection: IP42 (splash-resistant)

Integrated Controls:

• Power on/off with key switch

• Treatment timer (0-60 minutes, 1-minute increments)

• Intensity adjustment dial (5-15 mW)

• Emergency stop button (red, illuminated)

Display Panel: LCD screen showing:

• Current UV output power (mW)

• Total fluence delivered (J/cm²)

• Treatment time elapsed/remaining

• System status indicators

• Battery level (if portable model)

3. Operating Specifications

3.1 Dosimetry Parameters

Irradiance at Needle Tip: 5-20 mW/cm²

• Adjustable based on treatment protocol

• Real-time monitoring via photodiode sensor

Fluence (Dose) Range: 10-100 mJ/cm²

• Calculated from: Fluence = Irradiance × Time

• Automatic shutoff at preset dose limit

Treatment Duration: 5-30 minutes typical

• Programmable via control unit

• Maximum safety limit: 60 minutes

Irradiation Volume:

• Primary zone: 0.5-2 cm³ (immediate vicinity of needle tip)

• Secondary zone: 2-5 cm³ (reduced intensity, peripheral effects)

3.2 Safety Thresholds

Maximum Single Dose: 100 mJ/cm² (based on far-UVC safety data) Maximum Daily Dose: 300 mJ/cm² cumulative Automatic Shutoff Conditions:

• Preset dose reached

• Fiber disconnection detected

• Temperature exceeds safe limits

• Power supply fault

• User emergency stop activated

3.3 Blood Flow Considerations

Minimal Flow Obstruction:

• Annular space around fiber: 0.025 mm

• Estimated flow restriction: <5%

• Blood contact time with UV: 0.1-1.0 seconds (depending on flow rate)

Vein Selection Criteria:

• Recommended: Median cubital vein or cephalic vein

• Minimum vein diameter: 3 mm

• Adequate blood flow: >50 mL/min

4. Materials and Biocompatibility

4.1 Blood-Contacting Materials

All materials in contact with blood must meet:

• ISO 10993 biocompatibility standards

• USP Class VI certification

• Sterilization compatibility (EtO or gamma radiation)

Specific Materials:

• Needle: Stainless steel 316L (proven biocompatible)

• Fiber tip: UV-grade fused quartz (biologically inert)

• Hub: Medical-grade polypropylene (USP Class VI)

• Adhesives: Medical-grade cyanoacrylate or epoxy

4.2 Sterilization Protocol

Pre-Use Sterilization:

• Method: Ethylene oxide (EtO) gas sterilization

• Alternative: Gamma irradiation (25-35 kGy)

• Validation: Sterility Assurance Level (SAL) 10⁻⁶

Packaging: Double-peel sterile pouch with sterility indicators

Shelf Life: 3 years from sterilization date

5. Safety Features and Risk Mitigation

5.1 Multi-Layer Safety System

Layer 1 - Dosimetry Control:

• Real-time UV output monitoring

• Automatic dose limiting

• Fail-safe shutoff mechanisms

Layer 2 - Physical Safety:

• Key-switch activation (prevents unauthorized use)

• Safety interlock on connector (no emission if disconnected)

• UV emission indicator (visible LED shows when UV is active)

Layer 3 - Thermal Protection:

• Temperature sensors on LED and fiber

• Automatic shutdown if overheating detected

• Passive cooling design prevents burns

Layer 4 - Electrical Safety:

• Medical-grade isolated power supply

• Leakage current <100 μA

• Class II electrical safety rating

5.2 User Protection

No External UV Exposure:

• All UV light contained within fiber optic system

• No ambient UV emission during operation

• Fiber cladding prevents light leakage

Clinical Safeguards:

• Operator training certification required

• Treatment protocol documentation

• Patient monitoring during procedure

• Adverse event reporting system

5.3 Device Failure Modes

6. Clinical Use Protocol

6.1 Pre-Treatment Preparation

1. Patient Assessment:

   • Verify indication for UV blood irradiation

   • Check for contraindications (photosensitivity disorders, porphyria)

   • Obtain informed consent

   • Document baseline vital signs

2. Device Preparation:

   • Verify sterile packaging integrity

   • Connect UV source to fiber optic cable

   • Perform system self-test (automatic)

   • Set treatment parameters (dose, duration)

3. Site Preparation:

   • Standard IV insertion site preparation

   • Select appropriate vein (antecubital fossa preferred)

   • Apply tourniquet as needed

6.2 Treatment Procedure

Step 1 - Insertion:

• Insert needle using standard IV technique

• Confirm venous access (blood flashback)

• Secure needle with transparent dressing

• Remove tourniquet

Step 2 - UV Treatment:

• Initiate UV emission via control unit

• Monitor display for real-time parameters

• Observe patient for adverse reactions

• Maintain sterile field throughout treatment

Step 3 - Monitoring:

• Check vital signs every 5 minutes

• Observe insertion site for complications

• Document treatment parameters

• Patient communication and comfort

Step 4 - Completion:

• Automatic shutoff when preset dose reached

• Alternatively, manual stop if needed

• Turn off UV source before needle removal

• Remove needle using standard technique

• Apply pressure and dressing to site

6.3 Post-Treatment Care

• Monitor insertion site for 15 minutes

• Document any immediate adverse effects

• Provide patient discharge instructions

• Schedule follow-up assessment

• Record treatment data in medical records

6.4 Treatment Parameters by Indication

Experimental Protocol Example:

• Wavelength: 222 nm

• Irradiance: 10 mW/cm²

• Duration: 10 minutes

• Total Fluence: 60 mJ/cm²

• Frequency: Once daily for 3-5 days

Note: These are conceptual parameters and would require clinical trial validation.

7. Engineering Considerations

7.1 Optical Design Calculations

Light Transmission Efficiency:

Total System Efficiency = LED Output × Coupling Efficiency × Fiber Transmission × Diffuser Efficiency

Example:
= 15 mW × 0.85 × 0.70 × 0.80
= 7.14 mW delivered to blood

Fluence Calculation:

Fluence (mJ/cm²) = (Power × Time) / Area

For cylindrical irradiation zone:
Area = 2πrL (where r = radius, L = length of irradiated zone)

Example for 3 mm irradiation length, 2 mm radius:
Area = 2π × 0.2 cm × 0.3 cm = 0.377 cm²

Fluence for 10-minute treatment at 7 mW:
= (7 mW × 600 s) / 0.377 cm²
= 4200 mJ / 0.377 cm²
= 11.1 J/cm²

Note: Actual fluence will be lower due to blood absorption and scattering.

7.2 Thermal Management

Heat Generation:

• LED: ~85% of input power becomes heat

• 15 mW optical output requires ~100 mW electrical input

• Heat dissipation: ~85 mW

Cooling Strategy:

• Aluminum heatsink: 20°C/W thermal resistance

• Forced air cooling (optional): Miniature fan, 0.5 CFM

• Temperature rise: <10°C above ambient

Fiber Heating:

• Minimal absorption in fused silica at 222 nm

• Expected temperature rise in fiber: <2°C

• Blood cooling effect prevents tissue heating

7.3 Mechanical Design

Needle Strength:

• Stainless steel 316L tensile strength: 515 MPa

• Safety factor: >5 for insertion forces

• Buckling resistance: Adequate for 21G × 50 mm

Fiber Protection:

• Strain relief at all connection points

• Minimum bend radius enforcement (15 mm)

• Protective sheath along flexible section

Connector Durability:

• Rated for >50 connection cycles

• Locking mechanism: 2 N retention force

• Sterile barrier integrity maintained

7.4 Electrical Design

Power Requirements:

• Input: 100-240 VAC, 50/60 Hz (medical-grade adapter)

• Output: 12 VDC, 2A maximum

• Battery backup option: Li-ion, 3-hour runtime

Control System:

• Microcontroller: Medical-grade ARM Cortex-M4

• UV photodiode sensor: Si-based with 222 nm filter

• Display: Low-power LCD, 128×64 pixels

• User interface: 4-button control, rotary encoder

Data Logging:

• Internal memory: 1000 treatment records

• Data fields: Date, time, dose, duration, user ID

• Export: USB interface for data download

8. Testing and Validation Requirements

8.1 Optical Performance Testing

UV Output Verification:

• Spectral measurement (190-300 nm range)

• Peak wavelength confirmation (222 ±2 nm)

• Power output calibration (±5% accuracy)

• Spatial uniformity mapping (diffuser tip)

Fiber Transmission Testing:

• Transmission efficiency at 222 nm

• Attenuation per meter

• Bend loss characterization

• Long-term degradation study (1000 hours)

8.2 Biocompatibility Testing

Required per ISO 10993:

• Cytotoxicity (in vitro)

• Sensitization (guinea pig)

• Irritation (rabbit)

• Acute systemic toxicity

• Hemocompatibility (hemolysis, thrombosis)

• Implantation (short-term, if applicable)

8.3 Sterilization Validation

• Bioburden testing (pre-sterilization)

• Sterilization efficacy (SAL 10⁻⁶ verification)

• Package integrity testing

• Accelerated aging studies (shelf life)

8.4 Electrical Safety Testing

Per IEC 60601-1 (Medical Electrical Equipment):

• Leakage current measurement

• Dielectric strength testing

• Ground continuity verification

• EMC testing (emissions and immunity)

8.5 Functional Testing

• Dosimetry accuracy (±10% tolerance)

• Safety shutoff verification (all modes)

• User interface functionality

• Environmental testing (-10°C to +50°C)

• Vibration and shock resistance

• Humidity resistance (95% RH)

8.6 Clinical Validation

Pre-Clinical Studies:

• In vitro blood irradiation studies

• Ex vivo viral inactivation testing

• Animal studies (safety and efficacy)

• Pharmacokinetic modeling

Clinical Trials (if pursued):

• Phase I: Safety and tolerability (20-30 subjects)

• Phase II: Dose-finding and preliminary efficacy (50-100 subjects)

• Phase III: Efficacy confirmation (200+ subjects)

• Long-term follow-up studies

9. Regulatory Pathway

9.1 FDA Classification

Expected Classification: Class III Medical Device

• Reason: Novel technology, direct blood contact, therapeutic intent

• Regulatory Route: Premarket Approval (PMA) required

Alternative: Class II with Special Controls

• If substantial equivalence to predicate device can be demonstrated

• Would require 510(k) submission

9.2 Required Documentation

1. Device Master File (DMF):

   • Complete design specifications

   • Materials and manufacturing processes

   • Quality control procedures

   • Risk analysis (ISO 14971)

2. Biocompatibility Data:

   • ISO 10993 test reports

   • Material safety data sheets

   • Extractables and leachables studies

3. Clinical Data:

   • Pre-clinical study reports

   • Clinical trial protocols and results

   • Statistical analysis of efficacy and safety

   • Literature review of UV blood irradiation

4. Manufacturing Documentation:

   • Quality Management System (ISO 13485)

   • Manufacturing process validation

   • Sterilization validation

   • Traceability procedures

5. Labeling and Instructions:

   • User manual (clinician-focused)

   • Patient information leaflet

   • Warning labels and contraindications

   • Training materials

9.3 International Regulations

European Union: Medical Device Regulation (MDR 2017/745)

• CE marking required

• Notified Body assessment

• Clinical evaluation report

Other Markets: Country-specific requirements (Health Canada, TGA, PMDA, etc.)

10. Manufacturing Considerations

10.1 Component Sourcing

Critical Components:

• 222 nm UV LEDs: Specialized suppliers (e.g., Crystal IS, Seoul Viosys)

• UV fiber optics: CeramOptec, Polymicro Technologies

• Medical-grade needles: BD, Terumo, B. Braun

• Control electronics: Custom PCB design and assembly

Supply Chain Management:

• Qualified supplier program

• Incoming material inspection

• Component traceability (lot numbers)

• Backup suppliers for critical components

10.2 Assembly Process

Clean Room Requirements: ISO Class 7 (Class 10,000)

• HEPA filtration

• Positive pressure environment

• Personnel gowning protocols

• Environmental monitoring

Assembly Steps:

1. Fiber optic preparation and cleaving

2. Diffuser tip attachment (precision alignment)

3. Fiber insertion into needle shaft

4. Hub assembly and fiber fixation

5. Connector attachment

6. Functional testing (pre-sterilization)

7. Packaging

8. Sterilization

9. Final inspection and labeling

10.3 Quality Control

In-Process Inspections:

• Dimensional verification (needle, fiber)

• Optical alignment check

• Leak testing (hub assembly)

• Visual inspection (defects, contamination)

Final Device Testing:

• UV output power measurement

• Electrical safety testing

• Functional verification (all features)

• Sterility verification (sample testing)

• Package integrity inspection

Statistical Process Control:

• Control charts for critical parameters

• Capability analysis (Cpk >1.33)

• Trend monitoring

• Corrective action procedures

10.4 Cost Estimation (Preliminary)

Per-Unit Manufacturing Cost (at 10,000 units/year volume):

• UV LED module: $50

• Fiber optic assembly: $30

• Hypodermic needle: $2

• Hub and connectors: $5

• Packaging and sterilization: $8

• Labor and overhead: $15

• Total COGS: ~$110 per unit

Development Costs (one-time):

• Design and engineering: $500,000

• Tooling and fixtures: $200,000

• Testing and validation: $300,000

• Regulatory submission: $500,000

• Clinical trials: $2-5 million

• Total Development: ~$3.5-6 million

Pricing Strategy (estimated):

• Manufacturing cost: $110

• Target gross margin: 70%

• Estimated wholesale price: $350-400 per unit

• Hospital/clinic price: $500-600 per unit

11. Risk Analysis (ISO 14971)

11.1 Identified Hazards

11.2 Risk Mitigation Summary

Design Controls:

• Dosimetry with automatic limits

• Multiple safety shutoff mechanisms

• Biocompatible, tested materials

• Electrical isolation and safety compliance

Manufacturing Controls:

• Sterile processing and validation

• Quality control testing (100% critical parameters)

• Traceability and lot control

• Validated sterilization process

User Controls:

• Comprehensive training program

• Clear instructions for use

• Warning labels and contraindications

• Adverse event reporting system

Post-Market Surveillance:

• Complaint handling system

• Periodic safety update reports

• Field corrective actions if needed

• Continuous risk-benefit monitoring

11.3 Residual Risks

After mitigation, residual risks are considered acceptable if:

• Severity × Probability = Low or Medium risk level

• Benefits outweigh risks for intended use

• Risks are disclosed in labeling

• No further risk reduction is practicable

12. Clinical Considerations and Contraindications

12.1 Indications for Use (Proposed)

Primary Indication:

• Investigational adjunct therapy for viral infections with significant viremia

Potential Applications (requires clinical validation):

• Systemic viral infections (influenza, COVID-19, etc.)

• Bloodborne viral infections (HIV, hepatitis - investigational only)

• Septicemia with viral component

• Immunocompromised patients with viral reactivation

Note: All indications are theoretical and require extensive clinical trials.

12.2 Contraindications

Absolute Contraindications:

• Known photosensitivity disorders (porphyria, xeroderma pigmentosum)

• Severe coagulopathy (bleeding risk from needle insertion)

• Inadequate venous access

• Patient refusal or inability to consent

Relative Contraindications:

• Pregnancy (insufficient safety data)

• Pediatric use (dosing not established)

• Severe immunosuppression (theoretical risk)

• Recent photosensitizing medication use

12.3 Potential Adverse Events

Expected (Common):

• Insertion site pain/discomfort

• Minor bruising or hematoma

• Temporary vein irritation

Possible (Uncommon):

• Phlebitis or thrombophlebitis

• Localized infection

• Vasovagal response

Rare but Serious:

• Hemolysis (if UV dose excessive)

• Allergic reaction to materials

• Air embolism (technique-related)

• Nerve damage (insertion-related)

12.4 Monitoring Requirements

During Treatment:

• Vital signs every 5 minutes

• Insertion site observation

• Patient symptom monitoring

• Device parameter monitoring (display)

Post-Treatment:

• Complete blood count (CBC) within 24 hours

• Liver function tests (if indicated)

• Viral load measurement (efficacy assessment)

• Follow-up at 24 hours, 1 week, 1 month

Long-Term Surveillance:

• Cumulative exposure tracking

• Late adverse event monitoring

• Efficacy outcome assessment

13. Future Enhancements and Research Directions

13.1 Technology Improvements

Next-Generation Light Sources:

• Higher power 222 nm LEDs (>50 mW)

• Tunable wavelength LEDs (210-230 nm)

• Improved electrical efficiency (>20%)

Advanced Fiber Optics:

• Hollow-core photonic crystal fibers (>90% transmission)

• Smaller diameter fibers (100 μm core)

• Multiple-fiber bundles for larger irradiation volume

Smart Dosimetry:

• Real-time blood flow sensing

• Adaptive dose control based on blood chemistry

• AI-powered treatment optimization

13.2 Alternative Delivery Methods

Catheter-Based System:

• Central venous catheter with UV delivery

• Longer treatment duration (hours)

• Larger blood volume irradiation

Extracorporeal Circuit:

• UV irradiation chamber outside body

• Similar to dialysis or apheresis

• Controlled blood flow and exposure time

• Potentially safer and more effective

Implantable Device:

• Long-term UV delivery for chronic conditions

• Rechargeable battery or wireless power

• Biocompatible encapsulation

13.3 Research Questions

Biological Mechanisms:

• Optimal wavelength for viral inactivation vs. cell safety

• Dose-response relationships in human blood

• Long-term effects of repeated UV exposure

• Immune system modulation by UV blood irradiation

Clinical Efficacy:

• Which viral infections respond best?

• Optimal treatment timing and duration

• Combination with antiviral medications

• Patient selection criteria

Safety Studies:

• Long-term hematologic effects

• Cumulative dose limits

• Potential for carcinogenesis (theoretical)

• Effects on blood coagulation factors

13.4 Combination Therapies

UV + Photosensitizers:

• Targeted viral inactivation with photodynamic agents

• Lower UV dose requirements

• Enhanced specificity

UV + Antiviral Drugs:

• Synergistic effects

• Reduced drug resistance

• Lower medication doses

UV + Immune Modulation:

• Combination with immunotherapy

• Enhanced immune response to viral antigens

• Potential vaccine adjuvant effects

14. Conclusion

This technical design presents a conceptual intravenous UV light delivery system using 222 nm far-UVC light, which current research suggests may have a safer profile than traditional UV wavelengths. The design incorporates:

Key Innovations:

1. Integration of fiber optic technology with standard hypodermic needle

2. Specialized light diffuser for uniform blood irradiation

3. Comprehensive dosimetry and safety controls

4. Medical-grade materials and biocompatible design

Critical Success Factors:

• Selection of 222 nm wavelength (safer far-UVC spectrum)

• Precise dosimetry to avoid cell damage

• Multiple redundant safety systems

• Rigorous testing and validation

• Regulatory approval pathway

Path Forward:

1. Extensive in vitro testing with human blood

2. Ex vivo viral inactivation studies

3. Animal safety and efficacy studies

4. Clinical trial design and execution

5. Regulatory submission and approval

6. Manufacturing scale-up and commercialization

Important Disclaimers:

• This is a conceptual design for research and educational purposes

• Extensive validation required before any human use

• Clinical efficacy is unproven and requires rigorous trials

• Regulatory approval (FDA, CE, etc.) is mandatory

• Potential risks must be fully characterized and mitigated

• Benefits must clearly outweigh risks in clinical studies

15. References

Based on the literature search conducted, key references include:

1. Buonanno M, et al. (2013). "207-nm UV Light—A Promising Tool for Safe Low-Cost Reduction of Surgical Site Infections. II: In-Vivo Safety Studies." PLOS ONE. DOI: 10.1371/journal.pone.0138418

2. Buonanno M, et al. (2013). "207-Nm UV Light - a Promising Tool for Safe Low-Cost Reduction of Surgical Site Infections. I: in Vitro Studies." PLOS ONE. DOI: 10.1371/journal.pone.0076968

3. Levashenko GI. (1999). "Ultraviolet irradiation of blood." Biomedical Engineering. DOI: 10.1007/BF02386162

4. "The potential of 222-nm wavelength ultraviolet light for medical applications: a review." Journal of Korean Society for Laboratory Medicine. DOI: 10.25289/ml.24.009

5. "222 nm UV-C Light Irradiation for Treatment of Infections." Springer. Available: https://link.springer.com/content/pdf/10.1007/978-3-031-55858-0_126-1.pdf

6. Kowalewski A, Forde NR. (2023). "Fluence-dependent degradation of fibrillar type I collagen by 222 nm far-UVC radiation." bioRxiv. DOI: 10.1101/2023.09.19.558392

7. Meinke MC, et al. (2021). "Wavelength, dose, skin type and skin model related radical formation in skin." Biophysical Reviews. DOI: 10.1007/S12551-021-00863-0

8. Hilge F, et al. (2025). "Label-free visualization and quantitative analysis of Far UV-C skin safety with dynamic optical coherence tomography with subcellular resolution." Biomedical Optics Express. DOI: 10.1364/boe.569995

Glossary of Terms

Far-UVC: Ultraviolet-C light in the 207-222 nm wavelength range, which research suggests may be safer for human cells than traditional UV-C (254 nm).

Fluence: The total energy delivered per unit area, measured in J/cm² or mJ/cm². Calculated as irradiance × time.

Irradiance: The power of UV light per unit area, measured in mW/cm² or W/cm².

Numerical Aperture (NA): A measure of the light-gathering ability of an optical fiber, related to the acceptance angle.

More on the harmfulness of UV frequencies: here
Skin irradiation for multiresistant pathogens: here
Different biological effects of near and far UVC: here
More on the use of UV light for viral infections: here




Summary: UV light has been used with medical success for decades. All I am proposing is a cheap and simple delivery mechanism.