About

Professor Gediminas "Gedi" Mainelis is a faculty member at Rutgers University, serving as a Principal Investigator at the Bioaerosol Laboratory within the Department of Environmental Sciences at the School of Environmental and Biological Sciences. His research focuses on the development of bioaerosol sampling, control, and generation methods, as well as the integration of bioaerosol sampling tools with advanced microbiological analysis techniques. He is engaged in aerosol exposure assessment and studies related to the health effects of nanoparticles, indoor air quality in "green" buildings, and new technologies to control particle emissions. His work aims to improve understanding and management of bioaerosols and airborne particles to enhance air quality and public health.

Research topics

• Environmental science
• Meteorology
• Computer Science
• Physics
• Sociology
• Biology
• Medicine
• Toxicology
• Nanotechnology
• Environmental chemistry
• Environmental health
• Virology
• Materials science
• Geography
• Chemistry
• Internal medicine
• Library science
• Engineering
• Telecommunications
• Environmental engineering
• Civil engineering

Selected publications

• Inactivation of airborne pathogen surrogates by triethylene glycol

  Applied and Environmental Microbiology · 2026-01-23 · 1 citations

  articleOpen accessSenior author

  ABSTRACT The COVID-19 outbreak brought to the fore the importance of airborne transmission in spreading human infectious diseases and highlighted the need for sustainable mitigation strategies. Triethylene glycol (TEG) has been documented as having microbicidal capabilities and has been proposed as one such mitigation strategy. Aerosolized TEG exhibits antimicrobial activity against airborne microorganisms. Grignard Pure Technology was developed to safely aerosolize TEG for decontamination of enclosed spaces. Here, we show that this TEG formulation effectively inactivates airborne microorganisms, resulting in 2 to 4.5 net log reduction in concentration of viable bacteria, viruses, and mycobacteria within 30–60 min at TEG concentration (aerosol + vapor) of ~0.7 mg/m 3 , which is well within the range considered safe for humans. Our data also demonstrate that aerosolizing both the test organisms and the antimicrobial product provides a more accurate and relevant measure of the product’s efficacy for indoor usage than traditional surface—or solution—based disinfection assays. Accurate evaluation of antimicrobial efficacy is a crucial step in adopting novel interventions and tools to control airborne pathogens that pose a public health risk. Our findings argue that testing protocols must match the intended use of any intervention. Given the safety concerns of aerosolizing human pathogens for direct testing of airborne infectious burden, we also advance an approach for selecting suitable surrogate microorganisms based on their phenotypic and biophysical similarity to corresponding pathogenic species. IMPORTANCE During the COVID-19 pandemic, personal protective equipment, social distancing, and even vaccinations proved sub-optimal in controlling the spread of COVID-19. Public health practice and the hierarchy of controls emphasize primary prevention, whereby the pathogen is removed or destroyed before exposure to the public. Triethylene glycol (TEG) has the potential to inactivate airborne pathogens and limit their spread. TEG is designated a “safer chemical” by the US EPA and has been used for decades in aerosol deodorizers and theatrical special effects. This study shows that aerosolized TEG is highly effective at eliminating a wide spectrum of viable airborne pathogen surrogates at concentrations well below the threshold of safety concern. Thus, it may afford significant protection against the transmission of infectious agents with pandemic potential.

  PublisherDOI

• Aerosol Delivery of Polyelectrolyte Surfactant—Antimicrobial Nanoparticles to the Lungs

  Pharmaceutical Research · 2026-01-09

  articleOpen access

  BACKGROUND: Lung infections affect over 80% of adults with cystic fibrosis, with Pseudomonas aeruginosa being a leading pathogen. Although antibiotics are frequently nebulized as standard treatments, the physicochemical environment of the diseased lung often limits their diffusion and overall effectiveness. Our previous studies showed polyelectrolyte surfactants (PS) to be a promising delivery system for cationic antimicrobials in vitro. This study seeks to expand that knowledge by evaluating their potential for nebulized delivery. METHODS: To achieve this, we evaluated their size and antimicrobial activity following nebulization; in vitro toxicity against epithelial cells and erythrocytes; and biodistribution and expression of inflammation markers following administration to healthy mice. RESULTS: The nanoparticle formulation exhibited a mucolytic effect on an artificial mucus model of cystic fibrosis mucus. Following nebulization, nanoparticles retained both their size and biological activity. Additionally, they displayed no observable toxicity in vitro against either human lung epithelial cells or erythrocytes; instead, epithelial cells treated with PS-based nanoparticles showed increased cell viability. Following administration of these formulations to mice via inhalation, over 70% of the recovered nanoparticles were retained in the lungs 24 h after treatment, with a small fraction being uniformly distributed to other tissues. A screen of key inflammatory cytokines revealed that inhalation treatment led to a slight increase of IL-6 in the liver and IL-18 in the spleen. These increases seem to be consistent with a minor inflammatory response. CONCLUSION: Overall, the results suggest that PS are a promising nanotechnology for the pulmonary delivery of cationic drugs.

  PublisherOA PDFDOI

• Development of an Advanced Personal Nasal Sampler (Pns) to Assess Exposure to Bioaerosols

  SSRN Electronic Journal · 2025-01-01

  preprintOpen accessSenior author
  PublisherDOI

• An Air Quality Digital Twin for Real-Time Outdoor Air Quality Monitoring and Prediction

  SSRN Electronic Journal · 2025-01-01

  preprintOpen access
  PublisherDOI

• Unveiling Microbial Diversity in Greek Urban Air and Recreational Seawater Using DNA Barcoding

  Atmosphere · 2025-09-14

  articleOpen accessSenior author

  Air and seawater samples were collected in 2022–2023 and analyzed through a common DNA extraction, purification, and Next-Generation Sequencing protocol. The study targeted bacteria, archaea, fungi, and plant-associated taxa to compare community structure across both milieus. Given the scarcity of data on environmental microbiomes in Greece, we aimed to investigate further the diversity and variability of these microbiomes for the first time, using barcoding to provide data on microbial signatures in the air and seawater. Sequencing data revealed significant spatial and seasonal variability and a high diversity and richness of microbiome communities in both habitats. After quality filtering, we detected 21 phyla and 345 genera of bacteria and archaea, 3 phyla and 149 genera of fungi, and 17 Viridiplantae orders in the urban air. At the same time, in the recreational waters, we isolated 20 phyla and 420 genera of bacteria and archaea, 2 phyla, and 53 genera of fungi and 19 orders of Viridiplantae. Many of the fungal and bacterial taxa detected in this study can be potentially pathogenic. These findings highlight the potential of DNA barcoding as a reliable tool for integrative environmental monitoring, offering insights into the composition of environmental microbiomes. Microbiome monitoring is valuable for the environment and health, and it will be more efficient by integrating DNA analysis with the development of open databases and artificial intelligence.

  PublisherOA PDFDOI

• Performance characteristics of respirable parallel particle impactors (PPI)

  Journal of Occupational and Environmental Hygiene · 2025-07-18 · 1 citations

  article1st authorCorresponding

  of ∼4 µm, with a BPC of 100%. Overall, the respirable PPI samplers, particularly their disposable models, show excellent adherence to the respirable aerosol sampling convention and contribute to the arsenal of tools for estimating exposures to respirable particles. The availability of PPI samplers operating at different flow rates offers flexibility in selecting a suitable sampler model based on available personal sampling pumps, anticipated concentrations of the respirable aerosol fraction, and desired sampling times.

  PublisherDOI

• A Central Role for Counter-Mapping with Marginalized Populations to Promote Resilience through Community-Driven Urban Design 

  Research Square · 2025-11-17

  preprintOpen accessSenior author
  PublisherDOI

• Using Personal Exposure Measurement to Manage Environmental Stressors

  2025-05-30

  article
  PublisherDOI

• Inactivation of Airborne Pathogen Surrogates by Triethylene Glycol

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-08-08

  preprintOpen accessSenior authorCorresponding

  Abstract The COVID-19 outbreak brought to the fore the importance of airborne transmission in spreading human infectious diseases and highlighted the need for sustainable mitigation strategies. Triethylene glycol (TEG) has been documented as having microbicidal capabilities and has been proposed as one such mitigation strategy. Aerosolized TEG exhibits antimicrobial activity against airborne microorganisms; Grignard Pure™ Technology was developed to safely aerosolize TEG for decontamination of enclosed spaces. Here we show that this TEG formulation effectively inactivates airborne microorganisms, resulting in 2 to 4.5 net log reduction in concentration of viable bacteria, viruses, and mycobacteria within 30-60 minutes at TEG concentration (aerosol + vapor) of ∼0.7 mg/m 3 , which is well within the range considered safe for humans. Our data also demonstrate that aerosolizing both the test organisms and the antimicrobial product provides a more accurate and relevant measure of the product’s efficacy for indoor usage than traditional surface - or solution - based disinfection assays. Accurate evaluation of antimicrobial efficacy is a crucial step in adopting novel interventions and tools to control airborne pathogens that pose a public health risk. Our findings argue that testing protocols must match the intended use of any intervention. Given the safety concerns of aerosolizing human pathogens for direct testing of airborne infectious burden, we also advance an approach for selecting suitable surrogate microorganisms based on their phenotypic and biophysical similarity to corresponding pathogenic species. Importance During the COVID-19 pandemic, personal protective equipment, social distancing, and even vaccinations proved sub-optimal in controlling the spread of COVID-19. Public health practice and the hierarchy of controls emphasize primary prevention, whereby the pathogen is removed or destroyed before exposure to the public. Triethylene glycol (TEG) has the potential to inactivate airborne pathogens and limit their spread. TEG is designated a “safer chemical” by the US EPA and has been used for decades in aerosol deodorizers and theatrical special effects. This study shows that aerosolized TEG is highly effective at eliminating a wide spectrum of viable airborne pathogen surrogates at concentrations well below the threshold of safety concern. Thus, it may afford significant protection against the transmission of infectious agents with pandemic potential.

  PublisherOA PDFDOI

• An air quality digital twin for real-time outdoor air quality monitoring and prediction

  Building and Environment · 2025-12-12

  articleOpen access
  PublisherDOI

Recent grants

• Consumer Exposure to Airborne Nanoparticles Released from Nanotechnology-Enabled Clothing

  NSF · $300k · 2012–2017

• Training Grant for the Joint Graduate Program in Exposure Science

  NIH · $2.6M · 2011–2022

• NIH Grant K01OH008029

  NIH · $235k · 2008

• Advanced Sampler for Measuring Exposure to Biological Aerosols

  NIH · $1.9M · 2016–2019

Frequent coauthors

• Paul J. Lioy

  56 shared

• Taewon Han

  48 shared

• Klaus Willeke

  University of Cincinnati

  32 shared

• Sergey A. Grinshpun

  University of Cincinnati

  32 shared

• Yevgen Nazarenko

  University of Cincinnati

  31 shared

• L. Calderon

  Environmental and Occupational Health Sciences Institute

  30 shared

• Tiina Reponen

  29 shared

• Kathleen Black

  Rutgers, The State University of New Jersey

  28 shared

Education

• Ph.D., Environmental Sciences

  Rutgers, The State University of New Jersey