Research

A Minimally-Invasive 3D-Printed Microneedle Array Applicator System (μNAAS) for Delivery of Therapeutics to Citrus Leaf Tissue

A Minimally-Invasive 3D-Printed Microneedle Array Applicator System (μNAAS) for Delivery of Therapeutics to Citrus Leaf Tissue

Huanglongbing (HLB) is the most severe citrus disease in the world, caused by the phloem-restricted bacteria Candidatus Liberibacter asiaticus. It has decimated the previously $9 billion citrus industry in Florida, reducing turnover to $3.28 billion as of 2018. Treatment must reach phloem to be effective, which is extremely challenging. This work reports the design, fabrication, and testing of an innovative, minimally invasive mechanical delivery system that can transport therapeutics to HLB-affected trees. We demonstrate direct delivery to phloem using a 3D-printed microneedle array affixed onto a mechanical applicator to realize the microneedle array applicator system (µNAAS)