The recent development of photonics and applications puts new challenges for systems using emission, transmission and modulation of light. For these reasons, novel optical materials attract a special interest for their enabling properties for novel technologies.

In this work, we performed the research on fundamental properties and the possibility of implementation of electro-optical response of Poly-3-hexylthiophene-2,5-diyl (P3HT) nanofibers, which belong to the class of organic semiconductor crystalline materials. Our research demonstrated that an external electric field allows controlling the orientation of nanofibers dispersed in a solution by changing the electrical properties of P3HT crystals. This method was used to introduce a collective alignment of P3HT nanofibers and to impact the optical properties of the colloid. The spectroscopic and polarization measurements show that P3HT nanofibers possess optical anisotropy in a wide range of visible spectrum. This property combined with the ability to manipulate the orientation of nanofibers dynamically, was used for direct phase and intensity modulation of transmitted light. Along with these investigations, several engineering and technology tasks were solved. We have designed the transverse electro-optical cell using all-optical-fiber approach, as well as the longitudinal electro-optical cell was fabricated using a novel polymer molding technique.

The obtained research results demonstrate the potential of P3HT crystalline nanofibers as a material class of large niche of applications, not only limited to photovoltaics but also being implemented in electro-optical systems to control light polarization and propagation.

Improving the health and well-being of humankind does not only constitute

part of our moral codes, but is also enlisted as the number three goal of

the 2030 agenda for sustainable development set by the UN. Fulfilling such

objective in the regions of resource-poor settings or for age groups with more

vulnerability to infectious agents demands immediate actions. This has necessitated

novel ways of rapid and ultra-sensitive diagnostics to provide compact

and affordable systems, e.g. for an early detection of bacteria and viruses.

The fields of bio-micro/nanoelectromechanical systems (BioMEMS/NEMS)

and lab-on-a-chip (LoC) have been founded based on such demands, but

critically challenged by problems partly associated with manufacturing and

material domains and biosensing methods. The fabrication methods for the

miniaturization of features and components are often complicated and expensive,

the commonly used materials are typically not adaptable to industrial

settings, and the sensing mechanisms are sometimes not sensitive enough for

the detection of lowly-concentrated samples.

In this thesis, new methods of ultra-miniaturization, as well as conventional

cleanroom-based techniques, for nanopatterning of well-defined topographies

in off-stoichiometry thiol-ene-(epoxy) polymers are presented. In addition,

their use for several sensing applications has been demonstrated. The

first part of the thesis gives an introduction to the field of BioMEMS/NEMS.

The second part of the thesis presents a technical background about the

prevalent methods of polymer micro- and nanofabrication, implementation

of the resulting polymer structures for different sensing applications, along

with the existing challenges and shortcomings associated with state of the

art. The third part of the thesis presents e-beam nanostructuring of thiol-ene

resist, for the first time, achieving the smallest and densest features reported

in these polymer networks. The thiol-ene-based polymer also represents a

novel class of e-beam resist resulting in structures with reactive surface nature.

The fourth part of the thesis demonstrates the use of thiol-ene-epoxy

systems for nanoimprint lithography and further shows the structuring of

high-aspect-ratio and hierarchical topologies via single-step UV-NIL. The fifth

part of the thesis introduces Micro- and NanoRIM platforms for scalable and

off-cleanroom manufacturing of microfluidic devices and nanostructuring of

materials in thiol-ene (-epoxy) systems. The sixth part of the thesis exhibits

the implementation of the noted nanofabrication methods for different

BioMEMS/NEMS applications including protein nanopatterning, simultaneous

molding and surface energy patterning, ultra-sensitive digital biosensing,

and facile quartz crystal microbalance (QCM) sensor packaging.