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US 11,442,049 B2Granted
Method for producing a purple complex for the presence of lead using sodium rhodizonate without use of strong acid
OwnerFrederic G Dewalt, David C Coxinventors
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Abstract
A method using ascorbic acid (Vitamin C) as part of a chemical test kit employing sodium rhodizonate as the coloring agent for producing a yellow-orange to purple color transition for detection of lead in various media eliminating the use of strong acid.
Claims21
A method of detecting lead in media or on objects using ascorbic acid without any use of any strong acid to convert the scarlet lead-rhodizonate compound to the purple (blue-violet complex) that is diagnostic for the presence of lead when using sodium rhodizonate using the following steps:
- (a) exposing the media or object to an acid to dissolve the lead to form Pb+ ions;
- (b) exposing the media or object to a tartrate buffer fortified with ascorbic acid;
- (c) exposing the media or object to rhodizonate, wherein step b must be performed prior to step c);
- and,
- (d) monitoring the media or object for a visible color change.
2 more elements
Dependencies are inferred from the claim text.