Proteins, nucleic acids are best example of natural polymers. Similarly cellulose is also a natural polymer which acts as main structural component of plants. Usually natural polymers are composed by condensation polymerisation with the elimination of water molecule.
Drug-Laboratory Test Interactions. False-positive urine immunoassay screening tests for phencyclidine (PCP) and amphetamine have been reported in patients taking venlafaxine. This is due to lack of specificity of the screening tests. False positive test results may be expected for several days following discontinuation of venlafaxine therapy. Confirmatory tests, such as GC/MS will clear that misconception up asap...or if you are not using pcp and your dr is sceptical.
Another cause of nitrates to appear in urine is bacteria. Some bacteria cause a urinary tract infection (UTI) that induces a chemical reaction in the body to make an enzyme that changes urinary nitrates to nitrites. See more on urine nitrites.itrates are molecules and chemical compounds. As a chemical compound, it is one nitrogen and 3 oxygen atoms together. The reason they are important when measured in urine is that they have a negative acidic charge of -1. An imbalance of positive or negative acid in urine is an indicator of a possible metabolic issue.