A sensitive and compact optical detector based on digital lock-in amplification.

We report a sensitive, fixed-wavelength, lock-in-based optical detector built from a light-emitting diode, two colour filters, a photodetector, a small number of discrete analogue components, and a low-cost microcontroller development board. We describe the construction, operating principle, use and performance of the optical detector, which may be used for both absorption and fluorescence measurements in either a 10-mm pathlength cuvette or a low-volume (<100 μl) flow-cell. For illustrative purposes the detector is applied here to a cholesterol assay based on the enzyme-mediated conversion of (non-emissive) Amplex Red into the fluorescent dye resorufin, providing a detection limit of 200 nM - some four orders of magnitude lower than the typical concentration of cholesterol in human serum.

Rapid and mild synthesis of Au-NHC complexes in a simple two-phase flow reactor.

We describe a simple two-phase flow reactor which allows for the rapid synthesis of several Au(i)-NHC complexes in high yields (>88%), under mild conditions, and with minimal workup. Translation of the standard weak base method to a two-phase flow reaction prevents the common problem of decomposition to Au(0). The reaction can be scaled up more than ten-fold without loss in conversion efficiency.

A high-resolution polarimeter formed from inexpensive optical parts.

We describe a high resolution laser polarimeter built from commodity optical components. The optical rotation angle is determined by measuring the phase difference between two harmonically modulated polarised laser beams - an 'object beam' that passes through the sample under test and a 'reference beam' that bypasses the sample. The complete polarimeter may be assembled from low cost off-the-shelf parts for less than £300 (UK Sterling).

Screening and characterisation of CdTe/CdS quantum dot-binding peptides for material surface functionalisation.

Quantum dots (QDs) are promising nanomaterials due to their unique photophysical properties. For them to be useful in biological applications, the particle surface generally needs to be conjugated to biological molecules, such as antibodies. In this study, we screened CdTe/CdS QD-binding peptides from a phage display library as linkers for simple and bio-friendly QD modification.

A qualitative study of classical Chinese medicine in community health focusing on self-care: practitioner and staff perspectives.

Introduction: Classical Chinese medicine (CCM) encompasses many simple lifestyle recommendations which can be adopted into daily routines in support of short and long-term health outcomes. The rise in non-communicable diseases (NCDs) globally in recent decades has led to a need for cost-effective and scalable health care interventions to address lifestyle risk for NCDs in the community. This analysis explores the experience of staff and practitioners delivering a CCM community health care program designed to improve health behaviors in the community in rural Scotland.