Mixture of Intact RBC and Free Hemoglobin under a Low Cost, Low Power Photoacoustic System with Application in Hemolysis

Determining total hemoglobin in blood irrespective of hemolysis status using a high-power LED-based low-cost photoacoustic system

“…The overall trend is found similar to the one in fig. 3 (brown line) of [18]. The PA response of 100% lysed sample is clearly less intense than that of 0% lysis.…”

“…al. [18] was previously used to examine similarly prepared 13 different hemolysis conditions of 20% PCV sample. The study demonstrated a variation in PA amplitude with increasing hemolysis.…”

“…Here, to deliver a better understanding, the experiment has been repeated and the graph (brown line in fig. 3 of [18]) is redrawn using freshly generated dataset. The lysis percentages are replicated as in the published study: 0%, 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100%.…”

“…Thus, in the case of free Hb solution, the optical absorption falls, so as the overall optical attenuation and PA amplitude intensity. But, while a photon enters a RBC, despite of having low absorption coefficient, the photon experiences numerous internal reflections and gets totally or almost totally absorbed inside [17][18][19]24]. This is how under a NIR irradiation based PA system, RBC suspensions become more intense PA signal generator than free Hb solution of same THb, which explains fig.…”

“…There are other groups who also reported PA imaging using 850 nm and 532 nm irradiation respectively and measured THb along with other parameters [15,16]. However, it is crucial to note that the efficacy of such a system working in red-NIR range is dependent upon a priori knowledge of the hemolysis level within the sample [17,18]. In green light (532 nm) also, trends of PA amplitude start to bifurcate around at 40% PCV for suspended RBC and equivalent THb for Hb solution, as shown by Saha et.…”