Nanoneedles in Biomedicine: Precision-Engineered Platforms for Theranostic Applications

Cell engineering holds immense potential for treating complex diseases but is limited by immunogenic responses, low targeting potential, and high costs. Vertical nanoneedles, precisely engineered with a high aspect ratio, have emerged as a promising delivery vehicle to overcome these problems for minimally invasive drug delivery and cellular stimulation. This review critically examines recent advances in the design, fabrication, and application of nanoneedles for various purposes, with a primary focus on gene and drug delivery, biosensing, and cellular differentiation. Key findings highlight how the nanoneedles help in the transport of cell-impermeable biological molecules in a minimally invasive way for their efficient function in therapeutics or biosensing applications and their limitations. These applications extend to improving gene therapy and cellular-based treatments, making them a versatile tool in regenerative medicine.