Spectroscopic noninvasive measurement of hemoglobin compared with capillary and venous values in neonates.

Background: Venepuncture-related blood loss is a common cause of neonatal anemia. Currently, this is the only way to obtain hemoglobin levels. This causes distress for the infant but can also lead to the need for blood transfusions.

Measurement of transcutaneous hemoglobin concentration by noninvasive white-light spectroscopy in infants.

Objective: To compare transcutaneously spectroscopically measured hemoglobin values with venous hemoglobin values in infants.

Study Design: Prospective study in healthy preterm and term infants who were breathing spontaneously.

Results: Recordings were obtained from 85 stable infants (median gestational age at measurement: 36 weeks [range: 34-43 weeks]; median body weight: 1890 g [range: 1095-4360 g]).

Noninvasive reflection spectra provide quantitative information about the spatial distribution of skin chromophores.

In this work, a new method of analyzing noninvasive reflection spectra is presented. The approach explicitly models the inhomogeneity of chromophore distributions in living tissues and thus extracts not only apparent chromophore concentrations but also relative chromophore distributions in tissues. Furthermore, it works with spectra obtained with short source-detector separations where the diffusion theory of light transport through turbid media is not valid, and formerly presented methods thus fail.

Penetration studies of vitamin E acetate applied from cosmetic formulations to the stratum corneum of an in vitro model using quantification by tape stripping, UV spectroscopy, and HPLC.

The skin activation and penetration capability of vitamin E acetate as an ingredient in a basic o/w cream (lamellar type), in liposomes (Rovisome) and microparticles (Roviparts), was investigated under in vitro conditions (BUS model) by the adhesive stripping method. The aim of the study was to compare the analytical results obtained by UV spectroscopy (transmission) and the conventional HPLC method. For the quantitative spectrometric assay, a classical least-squares evaluation of the spectra between 265 and 350 nm, based on the constituent spectra, was used.