Cell Viability, Drug Screening, and Mechanism Study Under Mild Phototherapy Integrated Chemotherapy (PIC).

Phototherapy integrated chemotherapy (PIC) offers a promising cancer treatment strategy as single chemotherapy approaches are less effective due to tumor heterogeneity and drug resistance, and phototherapy often involves harmful radiation, and the potential of mild phototherapy to enhance chemotherapy remains underexplored. Cancer cells, as key drivers of tumor metastasis, are crucial targets, but current methods for visualizing their response to theranostics are slow. Here, nondestructive real-time impedance spectroscopy to monitor cancer cell response, identifying an optimal light exposure time of 60 min and defined cell viability and resistibility through impedance measurements, achieving high correlation (92.45% and 99.82%) with standard methods is used, and it is demonstrated that mild phototherapy significantly enhance chemotherapy, especially with Lenvatinib in liver cancer cell treatments. Through an in-depth study, the "more light-aiding, less bonding (LALB) mechanism," meaning less conjugated chemical bonding within the excitation threshold, results in more pronounced light-aiding properties, is proposed. This photochemical interaction mechanism confirms that combining phototherapy and chemotherapy offers significant benefits with higher targeting and lower toxic side effects in cancer and disease treatments, providing a new strategy of photochemical interaction and coupling for drug screening and mild phototherapy integrated chemotherapy (mild-PIC) treatment evaluation, and further promotes the development of other advanced biomedical applications.