Theoretical Analysis of Magnetic Levitation Technique and In Vivo Validation on Oral Cancer Diagnosis

Biomedical magnetic levitation systems which are the combination magnets and optical observation tools have been applied in directing, clustering, separating, or determining the densities of biological cell structures under the influence of gravitation and magnetic forces. The utilization of magnetic levitation systems in cell type determination or viability studies and especially in cancer diagnostics is found to be remarkable, however, to our knowledge, these systems have not yet been managed in oral cancer diagnostic studies. In the present study, the designed magnetic levitation system was assembled with two $3 \times 12 \times 63 \mathrm{~mm}$ magnets with the same poles facing each other and an optical observation setup. The distance between the magnets and the paramagnetic ion density as two parameters that can tune the magnetic forces in these systems, were theoretically analyzed. For a linear measurement system, the highest sensitivity was achieved at a spacing of 2 mm between magnets, and paramagnetic ion Gd concentration of 30 mM, taking into account the component of the magnetic forces in the direction of gravity. The results of the theoretical investigation were tested and validated ex-vivo with micro plastic spheres of known density and commercial oral squamous cell carcinoma cell line (OSCC) (CAL-27) and healthy oral keratinocyte Primary Gingival Keratinocyte (PGK) cell line. Thereafter, the densities of oral epithelial cells obtained by brush biopsy from 10 people either with OSCC or benign oral lesions were measured with the prepared system in-vivo. The density of the cells taken from benign and cancerous individuals were measured as $1.050+-0.01$ $\mathrm{g} / \mathrm{cc}$ and $1.065+-0.005 \mathrm{~g} / \mathrm{cc}$. The cellular density values of the oral benign and malignant cells were successfully determined in-vivo by the developed magnetic levitation-based density