The objective of this research is to integrate nanophotonics with microelectromechanical systems (MEMS) to understand the regulation of gene expression under controlled perturbations. The approach is to develop luminous scanning probe-based platform for light transmission, concentration and live imaging at the tip. By adjusting the light intensity, one can directly perturb sub-cellular structures through nano-surgery or micro-ablation. Through the integrated near-field scanning optical microscopy, one can observe in real time the evolution of gene expression in live embryos during perturbation. The measurement data will set the foundation for an electronic library of gene expressions correlated to distinct perturbations.
This research will develop, for the first time, a versatile microsystem with tip-light manipulation, enhancement, probe actuation and sensing, and near-field imaging functions. Perturbing the microenvironment is a complementary approach to modifying the genetic components of the developmental network. Using nanophotonic microsystems with unprecedented accuracy, this research can lead to significant advancement in the understanding of mechanisms crucial for robust development and engineering of substrates to guide organism development with controllable genetic characteristics.
This research can be of broader use on integrating heterogeneous nanosystems. It will also have a profound impact on biomedicine to enhance understanding of how environment-introduced ?errors? in gene action may lead to birth defects and cancer. The program has multiple integral educational initiatives, including the development of new teaching modules on nanophotonic Microsystems, cross-training of life science students at the frontiers of device engineering; and the establishment of ?Young Biomedical Engineers?(y-BME) program to recruit minority and female students.
This research outcome includes the development of a versatile near-field optical probing system and plasmonic surfaces for light manipulations. We have explored two novel directions: efficient directional radiator and plasmonic scanning tip for enhanced light confinement. Specifically, we experimentally demonstrated plasmonic directional radiator showing enhanced directivity and beam sweeping capability. By utilizing a series of subwavelength scale patterns on metallic surface, surface waves launched by a slit can be coupled into directive leaky wave modes and tailored in arbitrary direction of interest. In addition, we have studied plasmonic scanning probes offering enhanced light confinement and field enhancement in nanometer scale. By taking advantage of modes supported by plasmonic surface, surface waves can be effectively guided to tip apex and large near field enhancement can be achieved while confining energy within nanometer volume of interest. We also numerically investigated that temporal response of proposed probe geometries can be tailored through the proper choice of surface wave coupler designs. Intellectual merit: This research combines profound knowledge from optics, biology, precision engineering and nanofabrication. Nanofabrication is used to build the probe and test samples with typical size less than the diffraction limits. The electromagnetic wave behavior interfered with the material is studied and calculated with finite difference time domain algorithm. Precision feed-back loop has been for implemented for near-field distance control. Broad impact: The developed plasmonic probe with NSOM platform can be used for integrating heterogeneous nanosystems. It will also have a profound impact on biomedicine to enhance the understanding how environment-introduced error in gene action may lead to birth defects and cancer. The program has multiple integral educational initiatives, including the development of new teaching modules on nanophotonic microsystems, cross-training of life science students at the frontiers of device engineering, and the establishment of "Young Biomedical Engineers" (y-BME) program to recruit minority and female students. The success of our project on the development of efficient scanning probes and NSOM system will pave the way for the efficient future fluorescence microscopy system which is highly versatile for the detection and analysis of biological samples, such as bacteria, parasites, and even DNAs. Other than the academic achievements over the grant period, we also have put our efforts on the educational outreaches to enlighten undergraduate students especially whom to be motivated in academics. Our educational goal is not only for guiding undergraduate students, but also centers around providing new technological trainings to graduate students whom to be frontier biomedical engineers armed with expertise in both theories and experiments of near-field scanning fluorescence microscopy.
