S-STEM Scholar Leilani Boren's Blog

Introduction: Previous experiments have determined that the difference between certain sonication methods, the ultrasonic bath and the blender which have primarily been used this semester, is potentially unsubstantial. The testing of samples has also been indicating misinformation in the past since it has only recently been realized that 1:10 dilution of samples is necessary to achieve accurate and consistent results. Due to these conclusions, it was tested this week whether the three methods of sonication conducted thus far in the semester display similar changes over time purity values and concentration prior to any other experiments being done. Methods: Art prepared the stock solutions that have been made in the past month, which had been stored at -20 degrees Celsius, by leaving them at room temperature on magnetic plates in order to continuously stir each solution for the next 80 hours. Each container was covered in aluminum foil to prevent light degradation. Three solutions ...

 Introduction:      Previous experiments have so far established that analyzing phycocyanin extraction requires two major components; approximately 1:10 dilutions of sample in appropriate buffer or deionized water, and repeated readings which can be assessed in averages. Values for purity and concentration in the past few weeks have been consistent between each other, although much lower than anticipated. The previous semester produced crude extracts that were supposedly above even food grade purity requirements,  but the authenticity of  that data is now being questioned. This week primarily focuses on comparing the exact sonication practices from the previous semester, which was primarily ultrasonic bath sonification, while also comparing data from samples centrifuged for different durations of time.  Methods:      Arturo prepared the crude extract using 40 grams of dried spirulina and 400 ml of deionized water, with the...

 Introduction     Previous trials have indicated that in order to optimize phycocyanin extraction from Spirulina plantesis  and also achieve desired purity values with consistent repeatability, further focus is required to determine ideal testing methods and crude extract methodology. In an attempt to accommodate for future large scale production, the blending method has been used with high volumes of deionized water, as well as testing of samples done using both the Nanodrop One and Nanodrop 2000. This week adjustments were made to evaluate potential differences in blending times in terms of purity values, concentration values, and overall phycocyanin absorbance (absorbance at 620 nm). Further investigation was also conducted to finalize an opinion for sample testing, as there have been discrepancies between Nanodrop One and the Nanodrop 2000 in previous experiments.  Methods     The initial crude extract was developed by Artemio Chavez by sonicating ...