Cisplatin, a platinum-based chemotherapy drug, is widely used in the treatment of various types of cancer, including testicular, ovarian, bladder, and lung cancer. Its chemical formula is cis-[Pt NH3 2Cl2], and it belongs to the class of coordination compounds known as platinum II complexes. The photochemical properties of cisplatin play a significant role in its effectiveness as a cancer treatment.1. Photoactivation: Cisplatin can be photoactivated by exposure to ultraviolet UV or visible light. This photoactivation causes the complex to undergo structural changes, which can lead to the formation of highly reactive species. These reactive species can bind to DNA, proteins, and other cellular components, leading to cell damage and ultimately cell death. This property is particularly useful in cancer treatment, as it allows for targeted therapy with minimal side effects on healthy cells.2. Photodegradation: Cisplatin is sensitive to light and can undergo photodegradation, resulting in the formation of less active or inactive species. This process can reduce the effectiveness of the drug, making it essential to protect cisplatin from light exposure during storage and administration.3. Photosensitization: Cisplatin can act as a photosensitizer, meaning it can absorb light energy and transfer it to other molecules, generating reactive oxygen species ROS . These ROS can cause oxidative damage to cellular components, including DNA, proteins, and lipids, leading to cell death. This property can enhance the effectiveness of cisplatin in cancer treatment, particularly when combined with other therapies, such as photodynamic therapy.In summary, the photochemical properties of cisplatin, including photoactivation, photodegradation, and photosensitization, can impact its effectiveness in cancer treatment. Understanding these properties can help optimize the drug's use and develop new strategies for targeted cancer therapy.