Nanochemistry and biotechnology
Development of bioconjugates of luminescent quantum dots with antibodies for immunofluorescence microscopy
Borova M1., Kapush O2., Horiunova I1., Plokhovska S1., Pushkareva N1., Yemets A1.
1Institute of Food Biotechnology and Genomics, NAS of Ukraine,
Osipovskogo Str 2a., Kyiv 04123, Ukraine, marie0589@gmail.com

2V.E. Lashkaryov Institute of Semiconductor Physics NAS of Ukraine, Pr. Nauki 45, Kyiv 02000

Quantum dots (QDs) are kind of fluorescent semiconductors, which can be used as novel fluorescent probes, in addition they can be coated with hydrophilic materials and functionalized with antibodies, peptides, nucleic acids etc. Because of these unique photophysical properties, QDs are investigated as biosensors and labels in biological imaging [1]. 
The purpose of the present work is to functionalize Ag2S nanocrystals with monoclonal antibodies against cytoskeletal protein tubulin for microtubule visualization. Biosynthesis of Ag2S is described in [2]. In our research we modified existing protocol for covalent conjugation of gold nanoparticles with antibodies, which is reported in [3]. The critical reagents for the covalent coupling process are EDC and Sulfo-NHS they increase conjugation efficiency and create a more stable amine-reactive intermediate for binding with antibodies. We have revealed that bioconjugates had a symmetric luminescence spectrum with a maximum at 350 nm. We performed scanning electron microscopy (SEM) of produced Ag2S-antibody bioconjugates and developed a procedure for imaging of microtubules in epidermal root cells of Nicotiana tabacum plants. 

1.	Zhao M.X., Zeng F // Nanoscale Res. Lett. 2015. https://doi.org/10.1186/s11671-015-0873-8
2.	Borovaya M. et al  // Appl Nanosci. 2020 DOI 10.1007/s13204-020-01365-3
3.	Zhang L et al., // Biosensors and Bioelectronics, 2020. https://doi.org/10.1016/j.bios.2020.112370