Metal-based Membranes with Reduced Autofluorescence to Improve Detection and Imaging of Surface Analytes

Increasing the concentration of cells and microorganisms by filtration for solid phase imaging and counting is a rapid, sensitive tool. In addition, filtration is used for purification of genomic DNA from biological samples, which is a requisite initial step in the conducting many molecular diagnostic assays. Fluorescent analysis of these small particles directly on the filtration membrane without a transfer step would increase efficiency and reduce cost. However, this is typically limited by membrane autofluorescence.

The aluminum oxide-based membrane (AOM), Anopore� (Whatman Inc., New Jersey) has been proposed as a superior filter for solid phase imaging and counting due to its low surface adsorption, solvent resistance, high surface flatness, and high porosity. Although unaltered AOM has excellent properties as a solid support for biological filtration and solid phase imaging, an optically black treatment would notably improve optical performance for fluorescent imaging by reducing autofluorescence as well as non-specific binding (NSB) signal from below the filter surface. Ideally, such an optically black surface would not detrimentally alter the AOM surface or restrict filtration flow. This technology introduces a process for electroless deposition of nickel�boron (Ni�B) nanoparticles in the filter channels. The resulting optical improvement to AOM makes minimal alteration to the filter surface or pore area but increases optical absorption by orders of magnitude. This technology also describes a method for analysis of the deposited analytes.

Benefits
Analyte detection is a multibillion-dollar industry and is expected to continue to grow. It applicable to in vitro diagnostics, point of care markets, biological and chemical defense, and environmental detection.

Stage of Development
PCT application WO 04/048936 A2 has been published. This technology is available for developmental research support and licensing under either exclusive or non-exclusive terms

Additional Info
*Durtschi JD, Erali M, Bromley LK, Herrmann MG, Petti CA, Smith RE, Voelkerding KV (2005). Increased sensitivity of bacterial detection in cerebrospinal fluid by fluorescent staining on low-fluorescence membrane filters. J Med Microbiol.54:843-50.
*Durtschi JD, Erali M, Herrmann MG., Elgort MG., Voelkerding KV and Smith RE (2005). Optically improved aluminum oxide membrane through electroless Ni modification. J Membr Sci 248, 81�87

Inventor(s): Mark Herrmann, Roger Smith, Karl Voelkerding, Marc Elgort, Jacob Durtschi, Maria Erali

Type of Offer: Licensing



« More Medical Patents

---