This project contents two sections: In first section, magnetic nanoparticles (M) coated with aptamer was developed for the extraction of adenosine in urine samples followed by electrospray ionization-ion mobility spectrometry (ESI-IMS). The ion mobility spectrum of adenosine showed individual adenosine peaks at low concentrations and individual and dimer of adenosine peaks at high concentration. However, the ion mobility of eluent at low adenosine concentrations showed only peaks, related to dimer of adenosine. In other words, G-quartet captured two adenosine molecules between the top G-quartet and the two short stems, where they bonded to each other. The mass spectrometry of the eluent at low adenosine concentrations also validated the presence of dimer (m/z 535.95). The effect of parameters on extraction efficiency was investigated and under the optimized conditions, the linear dynamic range was found to be 0.1-5.0 µg/mL with detection limit of 0.03 µg/mL. The method was applied for the determination of adenosine in urine samples of patients with lung cancer. The results demonstrated the capability of the method. In second section, different deoxynuclotides and oligonucleotides were analyzed followed by electrospray ionization-ion mobility spectrometry. The reduced mobility values of deoxyadenosine monophosphate, deoxyguanosine monophosphate and thymidine monophosphate were calculated to be 1.10, 1.13 and 1.16 cm 2 V -1 S -1 respectively. The detection limits of these compounds were obtained 10.3, 12.1 and 1.9 pmol respectively. Also, different oligonucleotide sequences were analyzed by ESI-IMS and observed the same peakes with the reduced mobility values 1.31, 1.43, 1.52 and 1.76 cm 2 V -1 S -1 . The mass spectra of these compounds show that the peaks are related to negative ions with the same m/z.