Understanding the relationship between the sequence, structure, and function of biomolecules, which can serve as biomarkers for early disease detection, is vital for advancing molecular diagnostics. Consequently, highly sensitive optical readout methods to identify biomolecules,
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Understanding the relationship between the sequence, structure, and function of biomolecules, which can serve as biomarkers for early disease detection, is vital for advancing molecular diagnostics. Consequently, highly sensitive optical readout methods to identify biomolecules, such as proteins, are being developed. Single-molecule Förster resonance energy transfer (smFRET) has recently emerged as a promising technique for accurately identifying low-abundance proteins in samples as small as a single cell. However, the effectiveness of this fluorescence-based method depends on the precise design of donor-acceptor probe pairs to sequence labelled proteins. Recent advances have introduced the use of optically active atomic defects in two-dimensional hexagonal boron nitride (2D h-BN), also known as quantum emitters, as promising donor probes. Yet, achieving control over their spatial and spectral properties remains a significant challenge. This thesis investigates thermally induced wrinkles in exfoliated 2D h-BN crystals as potential nanochannels for the localization of both quantum emitters and biomolecules, the latter typically being in solution. The study reveals that the formation and morphology of these wrinkles are strongly influenced by the mismatch in thermal expansion coefficient between h-BN and its substrate. Additionally, the wrinkles exhibit variations in strain and effectively localize quantum emitters in the visible range. Initial experiments with water and ethanol provided a first indication of solution-based effects on wrinkle and emitter properties. The wrinkles remained stable upon exposure and even swelled, suggesting liquid uptake. Additionally, both liquids enhanced the fluorescence intensity of emitters on the wrinkles without necessarily activating those on the flat regions of the h-BN flakes. These findings highlight new research opportunities for using wrinkled 2D h-BN in optofluidic applications, potentially advancing the integration of quantum emitters in smFRET-based sensing devices.