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Preparation of Anthocyanin and Flavonols:
Cranberry anthocyanins and flavonols were extracted in a mini-blender with 20 ml of extraction solvent (85:15, ethanol: 1.5 M HCl) according to Boulanger and Singh [11]. The resulting homogenate was allowed to incubate at 4C overnight. Homogenates were filtered, and residue on the filter paper was washed with the extraction solvent to remove all pigments. The filtrate was diluted to 250 ml in a volumetric flask, and the solution spectrally analyzed. Flavonoid contents were estimated using published methods of cranberry anthocyanin and flavonol analysis [4-7].
Binding of Cranberry Pigments to Cotton and Nylon Fabrics:
Binding of dyes to fabrics is referred to as substantivity, and can be determined by measuring the reflectance of dyed cotton or nylon using spectrophotometer. Higher substantivity of the dye to cotton results in a lower reflectance (R) of the dyeing. The reflectance is measured at the wavelength of maximum absorbance of the dye concerned. Based on the f(R) value of the dyed cotton where [f(R)]=(1-R)^2/2R, also called Kubelka-Munk relation, the substantivity of a new dye is determined by doing a parallel dyeing against a known standard dye. The substantivity is diretly proportional to f(R). The higher the substantivity of a dye, the higher the f(R). f(R)is also expressed as K/S, where K is the coefficient of absorption and S is the coefficient of scatter.
After a series of dyeing using different dye concentrations with the same dye on same substrate (cotton) under same conditions, a relation of the function of R [f(R)] vs. the dye concentration is obtained, usually being a straight line. The slope of the line is used to estimate dye binding.
Results
The extract was found feasible to be used as a dyestuff at higher concentrations for Nylon-66 and Wool.
Dye-affinity of the fabric increases with the increase in the concentration of the extract used.
The extract gave very bright and acceptable shades for fabrics of coarser yarns, comparable to synthetic dyes, such as Nylamine Red A2B (Figure 6). 
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