Figure 1: Using nanotechnology to probe the sensitivity of cancer to medicines.

Barcoded nanoparticles (BNPs) were loaded with different drugs and corresponding DNA barcodes. (1) A cocktail of BNPs was injected intravenously. (2) The BNPs targeted the tumour and each of the drugs carried out its therapeutic activity inside different tumour cells. (3) Forty-eight hours later, a biopsy was taken from the tumour, and the biopsied tissue was dissociated into a single-cell suspension. (4) Each of the cells was sorted according to its viability (live/dead). (5) The barcodes were extracted from the live/dead cells and amplified using real-time PCR. The codes were detected by sequencing. The activity of the drugs inside the tumour was analysed by recording the number of each barcode found in the live cells, versus the number of barcodes found inside the dead cells. In this manner, the orthotropic tumour was used as a miniature laboratory, which was diagnosed with the nanoparticles at a cellular level. (6) Based on the screened results, a suggested treatment protocol was devised. In our studies, we found this predictive assay to achieve the best therapeutic results. The overall diagnosis takes less than 72 h.