Department of Chemistry

Research

Environmental Studies | Health-related Studies
Chemistry Education | List of Research Projects
Theses & Dissertations | Publications

Health-related Studies
Access to a diverse base of terrestrial and aquatic resources, researchers in this area look into the isolation and characterization of bioactive compounds from natural products.

Bioactive compounds. Natural products chemistry takes advantage of the species richness and diversity of the country. Recently, isolation and characterization of bioactive compounds from marine sponges Euspongia sp. (Callyspongia subarmigera) and Hippospongia sp. have been the focus of two studies.

Bioremediation. Use of the roots of water hyacinth managed to reduce lead ion concentration in vitro and in vivo. In the laboratory, the roots were found to absorb 147 mg Pb from aqueous solutions per gram of root. In mice, the kidneys and livers of animals fed with ground roots were found to contain remarkably less lead concentrations. For example, without feeding with roots, liver samples contained up to 3.7 ppm while samples taken from mice fed with roots only registered 0.7 ppm.

Forensic Studies
Phentermine is a drug closely related to methamphetamine. The maximum length of time that it can still be detected was determined from different samples; i.e., blood, urine and hair, using HPLC. It was found that the drug can still be detected from hair samples even after two weeks. Furthermore, the effect of paracetamol and alcohol on the detection of the drug was also investigated.

Trace studies involving chloramphenicol in chicken samples taken from different markets in Metro Cebu were also conducted. The profile of the presence of this antibiotic substance in the different samples was presented in studies carried out by undergraduate students.

High Performance Liquid Chromatograph (HPLC)
It is advantageous to separate mixtures rapidly and efficiently. Different compounds have different affinities for diverse solvents and adsorbent materials. This difference in affinity is the principle behind the separation effected by high-performance liquid chromatography (HPLC), where the solvent is called the mobile phase and the adsorbent material packed in a column is called the stationary phase.

A modular Knauer HPLC is available in the department and has been utilized for the separation of compounds found in natural product extracts as well as antibiotic residues found in chicken livers. The HPLC is a good complement to the FTIR, as isolated compounds can be partially characterized by infrared spectroscopy. If standards are also present, a compound may be identified by comparison of retention times.

Fourier Transform Infrared (FTIR) Spectrophotometer
Materials absorb infrared radiation causing their chemical bonds to vibrate. These absorption bands are characteristic of specific types of chemical bonds. Assignment of these bands will yield clues to the identity of an unknown sample. Furthermore, when a standard is available, comparison of the spectra of standard and unknown will determine the exact identity of the sample.

The department has a Perkin-Elmer Paragon 2000 FTIR spectrophotometer, which is used for teaching and research. The instrument is used by B.S. Chem. students in advanced organic chemistry, instrumental analysis and advanced inorganic chemistry. Undergraduate and graduate students also use the instrument for research, probing the structures of organic and inorganic substances. Isolates (see HPLC) from natural products may also be subjected to infrared spectroscopy to gain clues to the identity of the sample.

Samples submitted by faculty and students from other departments and colleges are also analyzed using the instrument. These samples range from chemically-altered surfaces to pharmacologically important compounds. The department also accepts, for a fee, samples from pharmaceutical companies and other industries and the general public.