Integrating sphere-based spectroscopic system for point-of-care DNA detection in plant tissues

Overview

This technology offers a fast, cost-effective, and nondestructive approach for point-of-care DNA detection in plant tissues using an enhanced visible and near-infrared (VNIR) spectroscopy method. By employing a single integrating sphere system coupled with the inverse adding-doubling (IAD) method, the platform separately measures the optical absorption and scattering properties of plant tissue. Absorption spectra reflect chemical composition, including DNA and RNA content, while scattering spectra reveal structural attributes such as cell density and particle distribution. This dual-parameter approach enables more objective and accurate assessment of genetic content compared to conventional diffuse-reflectance VNIR techniques, making it well suited for screening genome-edited crops, detecting single-nucleotide polymorphisms, and identifying larger genetic inserts directly in the field, greenhouse, or warehouse.

Technical specifications

• Integrating sphere-based VNIR system: Captures both absorbed and scattered light from plant tissue samples, enabling separation of absorption and scattering contributions using the inverse adding-doubling method
• Dual-parameter measurement: Absorption spectra correlate with chemical composition (DNA, RNA, and other biomolecules); scattering spectra correlate with tissue structure, density, and particle characteristics
• Nondestructive and rapid analysis: Eliminates the need for time-consuming sample preparation, lab-based real-time quantitative PCR, or Sanger sequencing for initial screening
• Field-deployable design: Can be operated in field, greenhouse, or warehouse-like environments without specialized laboratory infrastructure
• Validated methodology: Previously demonstrated for quality assessment of fruits and vegetables, including analysis of apple skin and flesh tissue
• Predictive modeling: Combines spectral data with qPCR and sequencing reference data to build and validate DNA prediction models

Technology readiness level

The integrating sphere-based spectroscopic system has been validated in prior studies for measuring optical absorption and scattering properties of plant tissues, including quality assessment of apple skin and flesh. The current project aims to extend this capability specifically to DNA detection in plant tissues over a 12-month period. Planned validation activities include establishing qPCR and Sanger sequencing reference procedures, collecting paired spectral and molecular data from plant tissue samples, and building and verifying predictive models for DNA content. Upon completion, the technology is expected to reach a readiness level suitable for pilot deployment in agricultural breeding programs, regulatory screening workflows, and field-based crop monitoring applications.