2Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
3Central Scientific Research Institute of Tuberculosis, Russian Academy of Medical Sciences, Yauzskaya Alley 2, 107564 Moscow, Russia
4Nikitsky Botanical Garden, National Scientific Center, Ukrainian Academy of Agrarian Sciences, 98648 Yalta, Ukraine
* To whom correspondence should be addressed.
Received June 23, 2010; Revision received July 16, 2010
Two monoclonal antibodies (mABs) raised against plum pox virus (PPV) were shown to recognize its D, M, and C strains. Conjugates of the antibodies with colloidal gold (CG) nanoparticles averaging 26 nm in diameter were synthesized. The binding constants of PPV with both the native and conjugated mABs were determined using a Biacore X device. The complexes between the CG–mAB conjugates and plum pox virions were examined by means of transmission electron and atomic force microscopy. Using the conjugates with optimal component ratio, an express immunochromatographic assay of PPV was developed with a detection limit of 3 ng/ml and duration of 10 min. The assay was tested for PPV detection in samples of stone fruit tree leaves and demonstrated a good compatibility with the data obtained by “sandwich”-ELISA. The developed assay can be used in the field and applied for monitoring viral infection and for quarantine purposes.
KEY WORDS: plum pox virus, monoclonal antibodies, colloidal gold, transmission electron microscopy, atomic force microscopy, immunochromatographic assay