Analytical Strategies for Monitoring Pharmaceuticals and Natural Product Components in Clinical and Nutritional Matrices

My research integrates analytical chemistry with biomedical and nutritional sciences to develop practical, cost-effective methods for detecting pharmaceuticals and active natural product compounds in complex biological and food-based matrices. This interdisciplinary approach addresses critical needs in public health, drug safety, forensic science, and food quality assurance, while providing undergraduates with meaningful, hands-on research experiences.

Our projects have encompassed the extraction and detection of therapeutic drugs, veterinary antibiotics, and natural product components in serum, urine, and food samples. Using High-Performance Liquid Chromatography (HPLC), my group has investigated the analysis of mitragynine, the active alkaloid in Mitragyna speciosa (Kratom), supporting ongoing efforts to characterize natural products with potential pharmacological or toxicological significance.

In drug monitoring and forensic applications, we developed a rapid colorimetric test for gamma-hydroxybutyrate (GHB, commonly known as “Liquid X”) in urine samples, which was further adapted into an on-site detection method using a portable, wireless UV/Vis spectrometer. This method provides valuable utility for both forensic investigations and emergency medical settings.

For pharmaceutical and food safety applications, my team created a solid-phase extraction method coupled with UV/Vis spectrophotometry to detect the antiepileptic drug phenytoin in the presence of chemotherapeutics, and developed an acid-based extraction protocol to identify tetracycline residues in milk. This advancement represents an important step toward affordable screening for food contamination.

Collectively, this body of work reflects a student-centered, application-driven approach to analytical chemistry that emphasizes real-world relevance in clinical diagnostics, drug monitoring, natural product analysis, and food safety. Through these projects, undergraduate students have gained valuable skills in method development, instrumentation, and data analysis, preparing them for successful careers in science and technology.

^ indicates undergraduate students at CSUSM, * indicates corresponding author

Karno Ng*. Tools for Enhancing Active Learning Experience in an Online Environment, eLearn Magazine, Aug. 14,  2026, https://doi.org/10.1145/3841557.3716635

Karno Ng*, Tyler Jackson^, Elizabeth Nicolas^, Daisy Monsivaiz^, Ting-An Lim^, Design of an Automated and Dynamic Visual Display with Acid-Base Reactions for Enhancement of Scientific Interest, The Chemical Educator. 2025, 30, 71-77.

Alondra Montejano^, Jennifer Nguyen^, Ngan Tran^, Mario Salgado^, Benjamin Duong^, and Karno Ng*. Application of Wireless Hand-held Sensors for Storm Water Management Program (SWMP) and Course-Based Undergraduate Research Experience (CURE). The Chemical Educator. 2025, 30, 58–62.

Karno Ng*, Maria Vidaca^, My Dang^. Evaluation of the Potential Application of a Portable and Wireless Spectrometer in the Forensic and Medical Field. International Journal on Engineering, Science and Technology(IJonEST). 2024, 6(4):385-396.

 Yuanyuan Jiang*, Kambiz Hamadani, Karno Ng, et al. Developing scalable hands-on virtual and mixed-reality science labs. Virtual Reality. 2024.  28, 173. 

Karno Ng* and Taehoon Ha^. “Extraction and detection of mitragynine in Kratom leaves by high-performance liquid chromatography.” Natural Product Research. 2025, 39(14), 4074-4079. Published online: March 27, 2024.

Karno Ng*, Samuel Alston, Samantha Castro^, Eric Santiago^. “Green Approach for Water Treatment”. International Journal on Engineering, Science, and Technology (IJonEST).  2024, 6(1), 89-99.

 Karno Ng*, “Implementation of New Communication Tools to an online Chemistry Course” Journal of Educators Online, 2018. 15(1).  

Veronica Anover, Karno Ng, Michelle Ramos Pellicia*, “A Study of the Effects of Students’ Socioeconomic Status on the Online Learning Environment”. Journal of Online Education 2017.

 Karno Ng*, “Development of an Online General Education Introductory Science Course with a Hands-on Lab Component for Non-science  Majors.”  The Chemical Educator 2015, 20, 294-300.

Todd A. Astorino*, Brian J. Martin, Lena Schachtsiek, Keau Wong & Karno Ng.  “Minimal Effect of Acute Caffeine Ingestion on Intense Resistance Training Performance.” Journal of Strength and Conditioning Research. 2011 25(6) 1752-1758.

Karno Ng* and Sean W. Linder, "HPLC Separation of Tetracycline Analogs: Comparison Study of Laser-based Polarimetric Detection with UV Detection," Journal of Chromatographic Science. 2003, 41, 460-466.

William C. Alston, Karno Ng*, "Rapid Colorimetric Screening Test for y-hydroxybutyric acid (Liquid X) in Human Urine," Forensic Science International. 2002, 126, 114-117.

Karno Ng, Ratnasamy Somanathan and Patrick J. Walsh*, "Synthesis of Chiral Resolved Pentadentate Sulfonamide-Based Ligands," Tetrahedron Asymmetry, 2001, 12, 1710- 1722.

Karno Ng, Thomas J. Edkins and Donald R. Bobbitt*, "Direct Specific Rotation Measurement of Amino Acids, Dipeptides and Tripeptides by Laser-Based Polarimetry," Chirality, 1999, 11, 187-194.

Donald R. Bobbitt* and Karno Ng, "Polarization Selective Detection of Biomolecules," Proc. Int. Conf. Lasers (1992), Volume Date 1991, 14th, 808-15.

Donald R. Bobbitt* and Karno Ng, "Chromatographic Analysis of Antibiotics in Food Materials, " J. Chromatogr., 1992, 624,153-170.

Donald R. Bobbitt*, Faye K. Ogasawara, Yunlong Wang and Karno Ng, "Renewable Optical Fiber Sensors Based on a Dynamically Modified Surface Interaction," SPIE Vol. 1648 Fiber Optic Medical and Fluorescent Sensors and Applications (1992), 227-237.

Karno Ng, Patrick D. Rice, and Donald R. Bobbitt*, "Identification and Quantitation of Gentamicin in Milk Using HPLC Separation and Laser-Based Polarimetric Detection," Microchemical Journal, 1991, 44, 25-33.

Thirty-Third International Conference on Learning, University of Hong Kong, Hong Kong. “Exploring Ungrading and Growth-Based Assessment In University STEM Courses: Reexamining How Feedback And Grading Shape Student Learning and Motivation” July 8, 2026 – Jul 10, 2026.

The American Association of Colleges and Universities (AAC&U), the 2026 Transforming STEM Higher Education Conference, Online. Karno Ng. “Beyond the Lab Bench: Enhancing Student Learning through Theme-Based Chemistry Instruction”. March 20, 2026.

The 2^nd World Chemistry Congress. Osaka, Japan. “Systematic Evaluation of the Application of Wireless Devices for Water Analysis in a Campus Storm Water Management Program,” May 23, 2024.

International Conference on Life Sciences, Engineering, and Technology (iLSET). San Francisco, California. “Development of Extraction and Detection Method for a Chemotherapeutic Drug with Phenytoin in Biological Samples,” April 18, 2024. (Virtual Oral Presentation)

International Conference on Engineering, Science, and Technology (IConEST). Las Vegas, NV. “A Green Approach for Water Treatment”. Oct. 22, 2023. (Virtual Oral Presentation)

American Association for the Advancement of Science (AAAS) Pacific Division, 99^th Annual Meeting, Cal Poly Pomona, CA. Symposium Talk: Active Learning Practices in Chemistry Courses: 'Active Learning Simulation Activities for an Analytical Chemistry Course,” June 15, 2018.    

 American Association for the Advancement of Science (AAAS) Pacific Division, 99^th Annual Meeting, Cal Poly Pomona, CA.  “Providing Hands-on Lab Experience for Students in a Fully Online Science Course”.  June 14, 2018

The 45th Western Regional Meeting of the American Chemical Society. San Marcos, CA . Division of Analytical Chemistry.  “Development of separation and detection method for chemotherapeutic drugs”. Nov. 7, 2015

 The 45th Western Regional Meeting of the American Chemical Society.  San Marcos, CA. Division of Chemical Education. ” Using technology   to reach out to the new generation for a fully online chemistry course.” Nov. 7, 2015

Faculty Center "Teaching Science: Engaging Students Digital/Electronic Solutions" Workshop, California State University San Marcos, “Teaching Chemistry Online". April 23, 2012

San Diego Science Festival, California State University, San Marcos, CA. Karno Ng & Judit Hersko, "The Art of Chemistry". April 1, 2009.

11th CSU Symposium on Universal Teaching, Cal Poly Pomona, Pomona, CA. "Teaching with Technology: Videoconferencing between Future Educators and 6th Graders." April 12, 2008.

San Diego and North County Chemistry Faculty Meeting, San Marcos, CA. "Innovative teaching and course structure in Quantitative Analysis."  April 20, 2001.

Federation of Analytical Chemistry and Spectroscopy Society Meeting, St. Louis, Missouri.  Karno Ng, T.J. Edkins, and D.R. Bobbitt, "Development and   Application of New Techniques for Probing Chiral Species Using Polarized Light." Oct. 2-7, 1994.

Federation of Analytical Chemistry and Spectroscopy Society Meeting, Detroit, Michigan.  Karno Ng and D.R. Bobbitt, “Ultrasensitive Measurement of Specific Rotation via Laser-Based Polarimetry: Application to the Study of Complex Bimolecular Structure." Oct. 17-22, 1993.

• Fall 2026: Selected, Toxicology Professional Mentoring Network (PMN), Fall 2026, Green Chemistry Professional Mentoring Networks Program, Beyond Benign. NSF-funded program (Award #2439515). 
• AY 2025-2026: Faculty-Student Collaboration Award, College of Science, Technology, Engineering and Mathematics (CSTEM), California State University at San Marcos
• AY 2024-2025: President's Award for Teaching Innovation & Excellence, California State University, San Marcos
• AY 2014-2015: Faculty-Student Collaboration Award, College of Science &  Mathematics, California State University at San Marcos
• AY 2007-2008: President’s Award for Excellence in Teaching and Learning. California State University at San Marcos
• 1999: Petroleum Research Fund, Summer Research Fellowship. American Chemical Society