2005 Research Fair Archive - Chemistry Abstracts
Synthesis of Poly(1-propargyl inosinic acid).
Previous work on viral RNA polymerase inhibitors has shown that some ribonucleic acid polymers are active against RNA directed DNA (RdD) polymerase, especially the reverse transcriptase enzyme of HIV. The objective of this project was to synthesize the RNA-like homopolymer, Poly(1-propargyl inosinic acid), and have it tested for activity against an RNA directed RNA (RdR) polymerase. The nucleoside and it's monophosphate and diphosphate analogs were synthesized in good yield. Future work will involve the synthesis and purification of the polymer from the diphosphate followed by biological evaluation.
Analysis of Pb and Se in Great Salt Lake Sediments
Initial study to quantitatively determine the Pb and Se concentrations at various depths in the sediment of the newly exposed Great Salt Lake shore. A 25.52 (±0.02) cm core sample was retrieved. The sample was sub-sampled and analyzed using atomic absorption and fluoresence spectroscopy. Pb was identified in concentrations ranging from 0 to 90.08 ppm. Se was found in the top layer at about 0.5 ppb. These levels are well below the EPA standards for safety but reveal an uneven distribution of these substances in the sediment. When studied in conjunction with published research, they indicate that the deposition rates of these two substances has varied with respect to time.
Fluoride Analysis in Green Tea
The fluoride level in green tea leaves (camellia sinensis) and in aqueous infusions prepared from the tea leaves has been investigated using a fluoride specific electrode and standard addition. The acid leachable fluoride content of dry tea leaves (Sen-Cha brand, packaged by Yamamotoyama) was determined to be 274.5 ppm ± 27.9 ppm (n=8). Infusions prepared in deionized water reached a maximum concentration of 1.75 ppm fluoride (n = 10) indicating that 64 % of the acid leachable fluoride can be extracted in hot water. Infusions prepared in municipal tap water (1.0 ppm fluoride) reached a maximum concentration of 2.74 ppm (n=3). When more highly fluoridated water was used for extraction, the tea leaves actually absorbed the fluoride from the water. Tea leaves were able to absorb up to 40% of the fluoride from water with a concentration of 10 ppm fluoride.