Fluorescence detection is a preferred method for many quantitative protein microarray assays in research and diagnostic applications due to its excellent sensitivity and potential for multiplexing. Use of multiplexed fluorescence-based assays on porous nitrocellulose though has been hampered by high backgrounds at shorter excitation wavelengths (such as the 532 nm fluorescence channel).
We have developed ONCYTE® SuperNOVA microporous nitrocellulose film slides to increase protein microarray assay sensitivity and dynamic range using fluorescent endpoints at multiple wavelengths. Use of SuperNOVA slides can lower your limit of detection with fluorescent endpoints by 3 – 4 orders of magnitude over competing film slides.
Figure 1. Improved Fluorescence Background and Signal-to-Noise
Figure 1. (A) Compared to other porous film slides, SuperNOVA slides have 10- to 60-fold lower backgrounds in both the 532 nm and 635 nm fluorescence channels. Shown are the average backgrounds obtained for 532 nm (green, 500 PMT/33% LP) and 635nm (red, 650 PMT/100% LP). (B) Due to their superior quality, SuperNOVA have approximately 25-fold higher Signal-to-Noise compared with other porous film slides (data obtained and imaged using identical scanner settings).
Figure 2. Improved Dynamic Range
Figure 2. The dynamic range of a typical fluorescent immunoassay on SuperNOVA is 7 orders of magnitude compared to 3 to 4 for competing slides. Shown is the fluorescence measurement at 532 nm for IgG detected from a serial dilution of rabbit serum. Similar results were obtained in the 635 nm channel (data not shown).