INTERNATIONAL JOURNAL OF PROGRESSIVE RESEARCH IN SCIENCE AND ENGINEERING, VOL.2, NO.7, JULY 2021. EDILBERTO MANAHAN., et.al: STABILITY STUDY OF URINE CREATININE LEVELS IN FILTER PAPER BASED METHOD TRANSPORT MEDIUM 65 Stability Study of Urine Creatinine Levels in Filter Paper Based Method Transport Medium Edilberto Manahan 1 , Jireh Besinio 1 , Danella Dela Peña 1 , Daniel De Leon 1 , Allen Dizon 1 Joze Monsanto 1 , Mariah Ocampo 1 , Aaron Toledo 1 , Ana Velasquez 1 1 Faculty of Pharmacy, Department of Medical Technology, University of Santo Tomas, Manila, Philippines. Corresponding Author: allensergio.dizon.pharma@ust.edu.ph Abstract: - Kidney disease is a major health problem worldwide, and creatinine is one of its markers for diagnosis. Alternative methods for the measurement of creatinine have been developed, including urine dried on filter papers. Studies proved its accuracy and reliability in comparison with conventional methods involving liquid urine. The researchers aimed to study the stability of human urine creatinine stored in various containers under different temperatures and durations. Urine samples from three (3) participants were subjected to eight (8) combinations of duration, temperature, and container, then triplicated to a total of 72 dried urine samples (DUS). Creatinine was measured using elution and reagent strip analysis. Findings showed that any combination of the physical factors could be used to store and transport DUS. There were no significant differences in the creatinine between one month and one week durations [t (70) = -0.801 (p > 0.05)], 25℃ and 4℃ [t (70) = 1.209 (p > 0.05)], and ziplock and microwavable plastic containers [t (7) = 1.209 (p > 0.05)]. The combination of one-week duration under 4℃ in microwavable plastic containers was the most stable, having the lowest mean difference (0.0 mg/dL). Storage of one month under 4°C in ziplocks showed the largest mean difference of 22.22 mg/dL, representing the least stable combination. The addition of physical variables, procurement of DUS from a broader range of participants with normal and impaired kidney functions, and usage of quantitative creatinine assay to eliminate subjective biases and increase the specificity of the method are recommended. Key Words: —Creatinine, dried urine, duration, temperature, container. I. INTRODUCTION “A hidden epidemic” is what renal experts say about the worldwide issue of kidney disease (Preidt, 2018) [1]. This major health problem affected 850 million people globally and is recorded to be the 7th leading cause of death among Filipinos. The National Kidney and Transplant Institute stated that the cost of treatment for kidney disease is quite expensive. As a major public health concern, a convenient and practical test is needed to diagnose and treat kidney diseases as early as possible. Feher (2017) stated that creatinine is a waste product in the blood produced by the body during muscle metabolism. It is filtered by the kidneys, and excreted in the urine, and serves as a marker for kidney problems through analysis in blood and urine samples. Blood tests are analyzed to estimate the GFR and the amount of creatinine present in the body [2]. Barr et al. (2004) showed that creatinine levels could also be measured in urine samples. This finding has resulted in its application to laboratories as one of the routine laboratory tests [3]. As far as the researchers are aware, no studies have been conducted about comparing creatinine levels from dried urine samples on filter paper with different temperatures, containers, and durations simultaneously. The primary objective of this research was to identify the stability of creatinine levels from dried urine samples on filter paper with regards to different storage temperatures, containers, and durations to support an accurate method of alternative for the routine urine creatinine test. Specifically, this study aimed:  To determine the effect of the following physical factors on the level of creatinine from the urine samples dried on filter paper: 1. Durations  One week  One month 2. Temperatures Manuscript revised July 15, 2021; accepted July 16, 2021. Date of publication July 18, 2021. This paper available online at www.ijprse.com ISSN (Online): 2582-7898