Quantifying nanomolar immunoglobulin G concentrations using aggregated nanodiamond particles and mass spectrometric analysis

Mhikee Janella N. Descanzo¹, Avinash A. Patil¹, Justin Benedict A. Agcaoili¹, Leevin S. Bacud¹, Wen Ping Peng^1*

¹Physics, National Dong Hwa University, Shoufeng, Hualien, Taiwan

* Presenter:Wen Ping Peng, email:pengw@gms.ndhu.edu.tw

We present by using aggregated nanodiamond particles (aNDs) and matrix assisted laser/desorption ionization time of flight mass spectrometry (MALDI-TOF MS) quantification of immunoglobulin G antibody in the nanomolar (nM) concentration range is possible. The exceptional platform of aNDs in adsorption and immobilization of protein enhanced the direct mass analysis of few nM immunoglobulin G (IgG) ions by five order of magnitude as compared to the conventional MALDI-TOF MS and could be better than other techniques. Furthermore, the method has provided good quality mass spectra of protein solutions containing abundant amount of salt (500 mM - 1M) and buffer at different pH values. Lastly, the study elucidates the adsorption of IgG in different sizes of positively and negatively charged NDs (50nm-350nm).

Keywords: aggregated nanodiamonds, mass spectrometry, MALDI, nanomolar concentration, immunoglobulin G antibody