HPLC Determination of α-keto Acids in Human Serum and Urine after Derivatization with4-Nitro-1,2-phenylenediamine (Khalida Parveen Mahar, Kulsoom Ubedullah Abbasi, Muhammad Yar Khuhawar, Gulam Murtaza Mastoi, Abdul Hameed Channer, Shamroz Bano Sahito, & Abdul Jabbar Kandhro, Trans.). (2025). Pakistan Journal of Analytical & Environmental Chemistry, 14(1), 16-25. https://doi.org/10.21743/