Sweat does not contain human cells, so there is no way to extract DNA without cells; Sweat is human body fluid, which contains some inorganic salts and water sugar, and does not involve DNA, so it cannot be identified.
Among them, the most commonly used samples are blood, blood stains, oral swabs, hair with hair follicles and so on. Other samples include: fetal amniotic fluid, fetal villi and fetal stream products during pregnancy; Sperm spots, mixed spots, muscles, teeth, nails and bones of the human body; Both toothbrushes and cigarette butts chewing gum can be collected and used in DNA paternity.