Nano/microtechnologies have been used to fabricate several novel surface plasmon resonant (SPR) devices for the applications in biomolecular sensing. Bioplasmonics have been used to describe the use of biomolecules as a part of the plasmon oscillating system to actively interact with nano/micro structure. We have reported a novel design of alternative dielectric layers to enhance the SPR signal quality and modulate its resonant position. Admittance loci method of thin film design has been used in the design of such a device. The revisit of Maxwell equations also leads to the development of a novel SPR device, which is based on the lateral propagation of surface plasmon wave along the metal-dielectric surface. For the realization of a hand-held SPR system, we have also developed three SPR waveguide sensors. A lateral flow microfluidic channel based on nitrocellulose membrane has been integrated with SPR waveguide sensor and achieved dynamic detection. An integrated SPR device, which couples OLED light source with nano grating structure and top sensing layer, has been tested and found anglar dependence emission. The extended applications of these fundamental principles and novel devices, especially for drug screening and disease diagnosis will be discussed during presentation.