The new labels can be used for whole body or in vitro cell bioimaging.

The new labels can be used for whole body or in vitro cell bioimaging. © The Hong Kong Polytechnic University

Next-generation fluorescent labelling agents are being developed from nanomaterials by scientists at The Hong Kong Polytechnic University.

Fluorescent labelling is widely used in biological research. Molecules that emit fluorescent colours are introduced to cells or tissues, where they bind to and ‘label’ different cell structures. As the bright colours are clearly visible, it allows us to see what is going on inside bodies, organs, or cells – in fact, most brightly coloured biomedical images are captured using some kind of fluorescent label.

The fluorescent labels used most commonly are organic dyes, such as fluorescein and cyanine, molecules like Green Fluorescent Protein (GFP) which is produced naturally in jellyfish, and quantum dots (QD).

These conventional labels generally work well, but they can sometimes be problematic. Their effects, for instance, may not last long enough to make observations over long periods of time, or may have a toxic effect on cells. This makes them less than ideal for certain areas of molecular biology.

Luckily, Tianhua Hao and his team at in Hong Kong are developing new labels using fluorescent nanomaterials called ‘upconversion nanophosphors‘ which are rare earth-metal ions like europium and terbium.

The new labels can be synthesised in one simple environmentally friendly step, and have much longer lifespans than their organic counterparts. They’re also very photostable – they don’t easily degrade when exposed to light – and are non-toxic. These properties make them ideal for biological imaging, both in the laboratory test tube, and in real-life contexts.

For further information contact:

Dr Jianhua Hao
The Hong Kong Polytechnic University