Autonomous microrobots are at the forefront of biomedical research as they are expected to be applied for specific tasks at the intracellular level such as cargo delivery, sensing, molecular manipulation, among others. Here, we report on a preparation of microrobots based on quinacridone and indigo, which are members of the organic hydrogen-bonded pigment family. The microrobots were fabricated by asymmetric platinum deposition on corresponding quinacridone and indigo microparticles that possessed a homogeneous size and shape distribution. The microrobots exhibited autonomous locomotion in the presence of hydrogen peroxide, which was further supported by UV irradiation. The organic pigment-based microrobots were studied in the presence of mouse colorectal carcinoma cells, and it was observed that they were internalized into the cells. Internalization was visualized using confocal laser scanning microscopy. This study reveals the possibility of fabricating hydrogen-bonded organic pigment-based microrobots for biomedical applications by employing the principles of nanoarchitectonics.
Keywords: cell internalization; confocal reflectance microscopy; hydrogen bonds; microrobots; nanoarchitectonics; organic pigments.