Biotechnological applications of the sepiolite interactions with bacteria: Bacterial transformation and DNA extraction

Among the various clay minerals, sepiolite, which is a natural nanofibrous silicate that exhibit a poor cell toxicity, is a potential promising nanocarrier for the non-viral and stable transfer of plasmid DNA into bacteria, mammalian and human cells. We first show here that sepiolite binds to bacteria, which can be useful in decontamination protocols. In a previous research we have shown that is possible to modulate the efficiency of the absorption of different types of DNA molecules onto sepiolite, and that the DNA previously adsorbed could be recovered preserving the DNA structure and biological activity. Taking advantage of both, the sepiolite/bacteria and sepiolite/DNA interactions, we show that pre-assembly of DNA with sepiolite and incubation of bacteria with this obtained biohybrid strongly improve the transformation efficiency, in a rapid, convenient and inexpensive method that doesn't require competent cell preparation. In addition, we also show that the controlled sepiolite and DNA binding capacities can be used to purify plasmids from bacteria, representing an advantageous alternative to onerous commercial kits. All of these results open the way to the use of sepiolite-based bionanohybrids for the development of novel biological models of interest for academic and applied sciences.