The invention provides a class of samples that model the
human body. This family of samples is based upon emulsions of
oil in water with
lecithin acting as the emulsifier. These solutions that have varying particle sizes may be spiked with basis set components (
albumin,
urea and glucose) to simulate
skin tissues further. The family of samples is such that other organic compounds such as collagen,
elastin,
globulin and
bilirubin may be added, as can salts such as Na+, K+ and Cl-.
Layers of
varying thickness with known index of
refraction and particle size distributions may be generated using simple crosslinking reagents, such as collagen (
gelatin). The resulting samples are flexible in each
analyte's concentration and match the
skin layers of the body in terms of the samples reduced scattering and absorption coefficients, mums and muma. This family of samples is provided for use in the medical field where lasers and
spectroscopy based analyzers are used in treatment of the body. In particular, knowledge may be gained on net
analyte signal,
photon depth of penetration,
photon radial diffusion,
photon interaction between tissue
layers,
photon density (all as a function of frequency) and on instrument parameter specifications such as resolution and required
dynamic range (A / D bits required). In particular, applications to delineate such parameters have been developed for the application of noninvasive glucose determination in the near-IR region from 700 to 2500 nm with an emphasis on the region 1000 to 2500 nm (10,000 to 4,000 cm-1).