skip to content

Cambridge Centre for Physical Biology

 

Photoacoustics resolves species-specific differences in hemoglobin concentration and oxygenation

Photoacoustic imaging (PAI) is an emerging biomedical imaging technology based on the conversion of light into ultrasound. It enables the non-invasive detection of the red blood cell protein haemoglobin (HB) and blood oxygenation (sO2). Lina Hacker, first author of the paper explains that these two biomarkers are widely used in photoacoustic research but the impact of genetic intra- and interspecies variability on these biomarkers has not been explored yet. In this work, authors identified that PAI is sensitive enough to detect species-specific differences in HB and sO2Blood phantoms (phantom is an object with defined properties to validate imaging devices) were used to compare photoacoustically measured HB with blood parameters determined by a haematology analyser and it could be determined that PAI is able to resolve differences in haemoglobin and haematocrit within and between species (mouse, rat), said Prof. Sarah Bohndiek senior author of the paper. Moreover, authors showed that technology could detect differences in oxygenation dynamics between mouse, rat, human, and was able to resolve the high oxygen affinity of naked mole rat blood (naked mole rats are able to bind oxygen more efficiently as an adaption to a life in a hypoxic underground environment). These results open up promising future directions for application of PAI for HB- and oxygenation-related research studies, such as to detect different forms or anaemia or hemoglobinopathies.

 

 

Figure legend:

Blood was taken from mouse, rat, naked-mole rat and human and analysed in vitro using Multispectral Optoacoustic Tomography (MSOT). The relative signal contributions of Oxy- and Deoxyhaemoglobin (HbO and HbR) were extracted and used to calculate the total amount of haemoglobin (THbMSOT), and oxygen saturation (sO2MSOT). THb was compared to the gold standard biochemical blood parameters (HB BC) measured using a haematology analyser. The species-specific oxygen dissociation curves were quantified using sO2MSOT and compared to the ones described in the literature. MSOT was able to detect intra- and interspecies differences in haemoglobin concentration and oxygenation. The Figure has been created using BioRender.com.

 

 

 

PAI resolves interspecies differences in haemoglobin (HB) 

PAI resolves interspecies differences in oxygenation dynamics

 

 

 

Reference: Hacker L, Brunker J, Smith ESJ, Quiros-Gonzalez I, Bohndiek SE. Photoacoustics resolves species-specific differences in hemoglobin concentration and oxygenation. J Biomed Opt. 2020 Sep;25(9). doi: 10.1117/1.JBO.25.9.095002.