2.6. Safety Analysis of Gold Nanorods

On the day after the scan, the kidney tissues of the two groups of mice were taken for HE staining, and the damage of renal tubular cells was analyzed. Take the mouse kidney tissue and cut it into 5 × 5 × 3 (cm) squares, and perform the steps of dehydration, paraffinization, embedding, sectioning, deparaffinization, and staining to obtain HE stained sections of the kidney tissue. Observe the pathological changes of the mouse kidneys under a light microscope (×200): 8 fields of view were randomly selected for each group, and the kidney damage of the mice was evaluated based on the expansion of the renal tubule lumen, blockage of the tube, flat cells, and cell necrosis and shedding. Set a total score of 1-5 points, where 1 point means no kidney damage, 2 points mean that the kidney damage is less than 1/5, 3 points mean that the renal tubule damage is between 1/5 and 1/2, 4 points indicate that the degree of renal tubular damage is more than 1/2, and 5 points indicate that all cells in the renal tubular have been damaged.