RESUMO
BACKGROUND: Human hemoglobin (Hb) is a tetrameric metalloporphyrin. Heme part contains iron radicle and porphyrin. The globin part has pairs of amino-acid chains. Healthy adults have "Hemoglobin-A" made of two alpha and two beta chains (α2 ß2) while a newborn baby has "Hemoglobin-A (α2 ß2)" and "Hemoglobin-F (α2 γ2)". There are few reports about absorption spectrometry of Hb in cord blood. We have here compared absorption spectrum of Hb in cord blood and maternal blood samples (adult blood samples) together. OBJECTIVE: This was done in two parts. Part 1 was about studying absorption spectrum of Hb in cord blood and maternal blood. Part 2 was about developing a comprehensive noninvasive technology and using the same for measurement of Hb in mother (adult) and new-born baby. DESIGN: Observational study. MATERIAL AND METHODS: Part 1. After IRB approval, 25 pregnant mothers enrolled for the study. Cord blood/neonatal blood samples were collected from placental end in ethylene diamine tetra-acetic acid (EDTA) tube after the delivery of fetus and placenta (venous blood). Maternal blood was collected by peripheral venepuncture before delivery/labor. Part 2. Using noninvasive technology for measurement of Hb in mother (adult) and new-born baby. After the necessary approval five pairs of mother and new-born were enrolled in the study to measure Hb by noninvasive method using our novel device. The novel device (SH-1) uses electromagnetic radiations of specific wavelengths between 520 and 580 nm. Light was projected on forehead for a few seconds, operating the light sources one by one. Of the projected light, some was reflected by the recipient's skin. This optical signal was collected by photosensors and converted to electrical signals. After amplification, this was then transmitted to processor unit. Later, Hbs values are displayed. The results were then tallied with standard laboratory methods in clinical laboratory. RESULTS: Part 1. As expected in our study; all blood samples showed Soret band of same peak and wavelength. We expected different spikes corresponding to four globin chains namely alpha, beta, gamma, and delta. But interestingly, both neonatal and maternal blood samples had identical peaks. Part 2. The results appear promising. The Hb as measured by noninvasive method matches well with standard laboratory test. SIGNIFICANCE: The energy level of Hb is low in deoxygenated state compared to oxyhemoglobin. In a state of high energy level, alpha and beta and gamma globin chains show obvious different peaks. Since cord blood and maternal sample was obviously venous or in deoxygenated state with low energy level, single peak of absorption was observed for all three globin chains. Since maternal and cord blood showed similar absorption spectra, it was possible to develop a common method for estimation of biomarkers - Hb in adults and new-borns alike.
