K. W. Kho

• PhD
• Senior Scientist at Tyndall National Institute

Upconversion luminescent nanomaterials have gained popularity recently due to their multitude of features that are attractive to a wide range of applications in the biomedical field. Unfortunately, their low quantum-yield (QY) has been a limiting factor. While attempts have been made to enhance their luminescence throughput over the past years, the...

Photonic crystal fiber (PCF) can be used as a microfluidic platform for surface-enhanced Raman spectroscopy (SERS)-based measurement of different samples. PCF can provide a long area of interaction for light, metal nanoparticles (NPs), and analytes incorporated into its holes. This paper provides a COMSOL simulation model for suspended-core PCF use...

The quantum yield (QY) evaluation of upconverting nanoparticles (UCNPs) is an essential step in the characterisation of such materials. The QY of UCNPs is governed by competing mechanisms of populating and depopulating the electronic energy levels involved in the upconversion (UC), namely linear decay rates and energy transfer rates. As a consequen...

Significance: Phantoms play a critical role in the development of biophotonics techniques. There is a lack of novel phantom tools in the emerging field of upconverting nanoparticles (UCNPs) for biophotonics application. This work provides a range of UCNP-based phantom tools and a manufacturing recipe to bridge the gap and accelerate the developmen...

Early diagnosis of oral cancer is critical to improve the survival rate of patients. Raman spectroscopy, a non-invasive spectroscopic technique, has shown potential in identifying early-stage oral cancer biomarkers in the oral cavity environment. However, inherently weak signals necessitate highly sensitive detectors, which restricts widespread usa...

This study aims to develop a multimodal scheme for diagnosing oral cancer non-invasively in its early stages and to assess the performance of an integrated diagnostic platform comprising of Raman and diffuse reflectance spectroscopy systems.

Oral cancer is the 16th most common cancer worldwide. It commonly arises from painless white or red plaques within the oral cavity. Clinical outcome is highly related to the stage when diagnosed. However, early diagnosis is complex owing to the impracticality of biopsying every potentially premalignant intraoral lesion. Therefore, there is a need t...

As they are widely implemented as features formed at a continuous metal surface, Surface-enhanced Raman spectroscopy (SERS) substrates are amenable to implementation in a microfluidic format. However, achieving reproducibility and repeatability in platform fabrication often requires methods that are complex and expensive, restricting transfer from...

A powerful new biophysical model is reported to assay nanocarrier lipid membrane permeability. The approach employs a nanophotonic biophysical membrane model as an assay to study oligonucleotide escape from delivery vector following fusion with endosomal membrane that relies on plasmonic hotspots within the receptor well, below the membrane to foll...

Plasmonic nanostructures are important across diverse applications from sensing through renewable energy. Periodic porous array structures are particularly attractive because such topography offers a means to encapsulate or capture solution...

A facile and economical route to preparation of highly ordered sliver pore or particle arrays with controlled pore-shape and size extended over cm² areas is described. The substrates are prepared at planar and curved surfaces via sphere-imprinted polymer (PDMS) templating using polystyrene spheres with diameters of 820, 600, or 430 nm. Nano-pore ar...

Dibenzoterrylene (DBT) molecules within a crystalline anthracene matrix show promise as quantum emitters for controlled, single photon production. We present the design and construction of a chamber in which we reproducibly grow doped anthracene crystals of optical quality that are several mm across and a few μm thick. We demonstrate control of the...