A new and robust tracer technology, based on Nano-sized encapsulated silica DNA sequences is presented. This cutting-edge technology enables a bond of each DNA sequence to a magnetic core particle and encapsulates it with silica. Therefore, one can have infinite sequences of DNA tracers. Each DNA tracer, with its identity signature, can be easily identified and characterized with no interferences. Unique chemistry makes these DNA tracers, either water-wet or oil-wet. The water-wet tracers can be used in hydraulic fracturing to precisely and accurately analyze flowback, both qualitatively and quantitatively. The oil-wet tracers can be used in evaluating the source and quantity of oil production in hydraulic fracturing. In-depth laboratory testing indicates that these tracers, unlike current industry used chemical tracers, are stable at high temperature, do not react with formation mineralogy to form reservoir rock plating, do not partition, and do not disintegrate over time. These tracers are injected in the liquid-laden slurry at very low concentrations and can be detected at parts per trillion.