Table 3.

Common biomarkers evaluated by biosensors for wound monitoring.

Type of marker	Indicator of:	Normal values	Illness values	Main mechanism of measurement
CHEMICAL
Glucosea	Insulin deficiency, diabetes mellitus	3.9–7.8 mM in blood	>7.8 mM in blood	Chronoamperometry, absorptiometry
IL-6b	Inflammation, elevated metalloproteinases	0 pg/μg on skin 0–2.4 pg/mL in blood	1.27 ± 1.7 pg/μg at wound >2.4 pg/mL in blood	ELISA, western blot
Lactatec	Hepatic disease, tissue hypoxia, hemorrhage, sepsis	0.5–1.5 mM in blood 1.0–3 mM on skin	>1.5 mM in blood >7 mM at wound	Chronoamperometry
pHd	Infection, acidosis, enzyme degradation rate, collagen deposition, fibroblast activity	4–7 pH of skin	7.15–8.90 pH at wound	Chronoamperometry, optical transitions
Oxygene	Metabolic activity, apoptosis, carbon monoxide	30–50 mmHg pO2 on skin 50–130 μL in blood 97% hemoglobin binding	5–20 mmHg pO2 in exudate 50–130 μL in blood <97% hemoglobin binding	Fluorescent sensing, clark-type electrochemical cell
PHYSICAL
Temperaturef	Inflammation, metabolic activity	31.1–35.4°C of skin	1.11°C increase at wound	Thermometer, thermogram, thermistor
Blood Pressureg	Hypertension	<115 mmHg systolic <80 mmHg diastolic	>115 mmHg systolic >80 mmHg diastolic	Strain gauge, auditory

^aChen et al. (2013).

^bBeidler et al. (2009); Huang et al. (2013); Tsuneyasu et al. (2014).

^cLöffler et al. (2011) and Rathee et al. (2016).

^dLambers et al. (2006); Gethin (2007); Morris et al. (2009), and Santos et al. (2014).

^eSchreml et al. (2010); Baura (2012b), and Luo et al. (2017).

^fKarlsbad and Kopp (1991); Ng (2009); Fierheller and Sibbald (2010), and Baura (2012c).

^gLawes et al. (2008) and Baura (2012a).