Lipid-polyelectrolyte nanoparticle delivery system for peptide-based biocides
A novel lipid-polyelectrolyte nanoparticle platform for foliar delivery of antimicrobial peptides into deep plant tissues. Designed to combat citrus greening disease (HLB) caused by Candidatus liberibacter asiaticus, the system uses Tween 80-stabilized lipid nanoparticles coated with polyelectrolytes to enhance leaf permeability and achieve approximately 60% encapsulation efficiency with confirmed peptide delivery at 2, 6, and 24 hours.
Overview
This technology addresses a critical challenge in agricultural biotechnology: the effective delivery of peptide-based antimicrobial agents into deep plant tissues. The platform centers on lipid nanoparticles (LNs) stabilized with Tween 80 and coated with polyelectrolytes, enabling foliar application of antimicrobial peptides that target Candidatus liberibacter asiaticus, the bacterium responsible for citrus greening disease (Huanglongbing, or HLB). By enhancing leaf permeability, the nanoparticle system allows potent bactericidal peptides to reach tissue sites where the pathogen resides, offering a new tool for managing one of the most destructive diseases affecting citrus production worldwide.
Technical specifications
Core technology:
- Lipid nanoparticles synthesized via high-shear homogenization
- Tween 80 surfactant stabilization at 0.5% concentration
- Polyelectrolyte coating at 0.5% concentration
- Approximately 60% peptide encapsulation efficiency under optimized conditions
- Nanoparticle size and zeta potential characterized using a Delsa Nano C Zetasizer
Delivery validation:
- Time-dependent peptide delivery confirmed at 2, 6, and 24 hours after foliar application
- Confocal microscopy with fluorescent lifetime imaging module (FLIM) used for visualization
- Control experiments confirmed polyelectrolyte inclusion is critical for effective delivery
- Antimicrobial peptides developed in-house against Candidatus liberibacter asiaticus
Planned optimization:
- Factorial study evaluating combinations of polyelectrolyte types, surfactant types and quantities, lipid composition, peptide variants, and shear rates
- Assessment of nanoparticle size, zeta potential, and encapsulation efficiency across conditions
- Qualitative delivery evaluation via fluorescent microscopy
- Quantitative delivery measurement via LC-MS or MALDI-TOF-MS analysis
Technology readiness level
The technology is at an early-to-mid stage of development. Proof-of-concept validation has been completed, demonstrating nanoparticle synthesis, approximately 60% encapsulation efficiency, and confirmed peptide delivery to deep plant tissues at multiple time points. The critical role of polyelectrolyte coating in enabling delivery has been established through controlled experiments. Ongoing and planned factorial studies will optimize formulation parameters to improve encapsulation and delivery efficiencies, advancing the platform toward broader agricultural application and potential commercialization.
About Texas A&M University, College Station
Texas A&M University in College Station is a comprehensive public research university and the flagship of The Texas A&M University System, combining broad academic strengths with a strong applied‑research culture. Industry collaborates on the Texas A&M‑RELLIS campus—an integrated education, research and testing environment that supports large‑scale experimentation and proving grounds—and through the Texas A&M Transportation Institute’s facilities in Bryan‑College Station. A statewide extension network connects university expertise to companies and communities across all Texas counties, enabling rapid piloting and deployment. Research is supported by competitive federal funding from agencies such as NSF, NIH, DOE, USDA and DoD, alongside state and industry sponsorship. Texas A&M Innovation provides IP management, licensing and commercialization pathways across the system.
Inquire about this partnering listing
Looking for
Industry applications
delivered to your inbox.