Electrochemical behavior and Square Wave Voltammetric Determination of Bilirubin Based on Nafion/Graphene Oxide Nanocomposite Glassy Carbon Electrode
Hayati Filik(*), Asiye Aslıhan Avan, Sevda Aydar
Istanbul University, Faculty of Engineering, Department of Chemitry, 34320 Avcılar Istanbul, Turkey
Abstract
A highly sensitive electrochemical sensor for the determination of bilirubin at the Nafion-electrochemically reduced graphene oxide (Nafion/ER-GO) modified glassy carbon electrode is reported. The electrochemical oxidation behaviors of bilirubin (BR) at the Nafion/ER-GO modified glassy carbon electrode were studied in acetone 0.05 M H2SO4 containing as the supporting electrolyte. The Nafion/ER-GO modified glassy carbon electrode exhibited
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Free heme, which is toxic, is degraded via cleavage of its tetrapyrrolole ring by heme oxygenase. Bilirubin exists in two forms in the body: indirect (unconjugated) and direct (conjugated). Indirect bilirubin, which doesn't dissolve in water, must travel to the liver to be changed into the soluble form, direct bilirubin. Normal levels of bilirubin in blood serum of adult range from 10−5 M to 10−6 M [1]. When the amount of bilirubin in the body exceeds the binding capacity of albumin, extra free bilirubin binds and deposits to various tissues, especially in the brain with deleterious effects. The importance of bilirubin analysis in clinical chemistry is related to diagnosis and prediction of haemolytic disorders in adults as well as in newborn infants …show more content…
All the experiments were carried out at room temperature. Bilirubin were purchased from Sigma (St. Louis, MO, USA), and they were all used as received. The desired weight of bilirubin was initially dissolved in a minimal amount of 0.1 M sodium hydroxide. Standard stock solutions (1.0×10−2 mol L−1) of the compounds (dopamine, ascorbic acid, uric acid and tocopherol) were prepared by dissolving appropriate amounts in ethanol. The solutions were protected from light and stored at 4°C. Before use, all sample solutions were prepared by appropriate dilutions to the desired concentration with distilled water. All potentials reported were versus the Ag/AgCl (3 M KCl). All of the measurements were carried out without removing dissolved oxygen. For all the electrochemical studies, 0.05 M H2SO4 was used as the supporting electrolyte unless specially stated. Graphene oxide (GO) was synthesized from natural graphite by a modified Hummers method [25,26]. Nafion/ER-GO-modified glassy carbon electrode was prepared according to a literature reported procedure
In this lab, the oxidation of a secondary alcohol was performed and analyzed. An environmentally friendly reagent, sodium hypochlorite, was used to oxidize the alcohol, and an IR spectrum was obtained in order to identify the starting compound and final product. The starting compound could have been one of four alcohols, cyclopentanol, cyclohexanol, 3-heptanol, or 2-heptanol. Since these were the only four initial compounds, the ketone obtained at the end of the experiment could only be one of four products, cyclopentanone, cyclohexanone, 3-heptanone, or 2-heptanone. In order to retrieve one of these ketones, first 1.75g of unknown D was obtained.
The purpose of this experiment is to create a complete genomic library of Aliivibrio fisheri through the use of the lux operon. The examination of the lux operon gene occurs through the extraction of the DNA of Aliivibrio fischeri and digest a large piece of DNA to smaller random pieces. The fragment of DNA will later be ligated together in plasmid. Plasmid acts as vectors to transport DNA from one organism to another. The DNA will then run through a UV-visible spectrophotometer to test the absorbance of the extracted DNA.
What is the normal fate of bilirubin, and what role does the liver play? Explain how Mrs. Fender’s cirrhosis is related to her jaundice. • Bilirubin is a product of the heme of hemoglobin formed during the breakdown of erythrocytes. The liver removes the bilirubin from the blood and excretes it into the intestines as bile. When the liver is damaged, bilirubin, which is a yellow pigment, spills over into tissues and the blood, thus giving the skin a yellowish coloring.
He does have a slight elevation in his total bilirubin is 0.3. Other liver function testing is normal. He has previously had a liver ultrasound back in October of 2014, showing hepatic steatosis, otherwise negative abdominal ultrasound. He has previously has declined evaluation by gastroenterology or hematology and he is still not sure that he wants to do that. He is not having any belly pain.
Drugs bound to protein are not able to be excreted by the body because it doesn’t filter into the glomerular tubule and this is mainly because of its large size. In this lab the experimental value for binding of acetaminophen to serum albumin was calculated to be 21.93%. The binding of different drugs differ greatly in their ability to bind to serum proteins. One major problem in performing this experiment was that the plasma was contaminated with mint wax-dental floss that was used to tie the ends of the dialysis tube. This affected the absorbance reading of the plasma sample and therefore we had to use the data of another group whose plasma sample wasn’t as
Unknown Lab Report Unknown # 25 By: Jenna Riordan March 19, 2018 Bio 2843 1. Introduction Microbiology is the study of microorganisms found in all different environments throughout Earth, from the hot thermal vents at the bottom of the ocean to the ice at the top of a mountain.
A comprehensive review of the other components of the CBC is one of the most important steps in the evaluation of low platelet count. The CBC can tell us whether other blood disorders may be present, such as, anemia (low red cell count or hemoglobin), erythrocytosis (high red blood cell count or hemoglobin), leukopenia (low white cells count), or leukocytosis (elevated white blood cell count). These abnormalities may suggest bone marrow problems as the potential
Chem 51LB Report Ngoc Tran - Student ID # 72048507 The purpose of this lab is to examine the composition of three components of gas products of elimination reaction under acidic condition by conducting the dehydration of primary and secondary alcohol, and under basic condition by conducting the base-induced dehydrobromination of 1-bromobutane and 2-bromobutane. Then gas chromatography is used to analyze the composition of the product mixtures. Gas chromatography (mobile phase) is used to analyze the composition of three components of the gas products. A syringe needle with gas product is injected into the machine, and the component is eluted and the composition is related to the column or the peaks.
1. Cocaine became popular when it started being used for more and more things as its uses became more and more known. Cocaine use originated around 5000 BECAUSE with the Incans of Peru. Cocaine was used as a stimulant to help the natives get through grueling, long, active days of work. As time went on the plant became an integral part of their lives; used as money, an herb and during religious ceremonies.
What are the primary pieces of evidence from the CBC that point to this diagnosis? Anemia is a condition that develops when a person’s blood lacks enough healthy RBC or hemoglobin. The effect is an insufficient amount of oxygen to the tissues. In Harold’s case, the main parts of evidence from the CBC include the low RBC, hemoglobin, and hematocrit.
In this experiment, 9-fluorenone, a ketone, was reduced to fluorenol, an alcohol. The product was then identified using melting point and IR data, and percent yield was calculated. Reduction is one of the two processes that occur during a redox reaction, and it involves the gain of an electron by one of the species. The other species in the reaction loses an electron, and is by definition oxidized. In this experiment, fluorenone, the oxidizing agent, was reduced, and sodium borohydride, the reducing agent, was oxidized.
“Cirrhosis is a common cause of death worldwide. In the United States, about 35,000 people die of complications of cirrhosis each year.” (Civan) The liver is an expansive, substantial organ that sits on the correct side of the abdominal cavity. With this in mind, the liver roughly weighs three pounds, is rosy darker in shading and feels rubbery to the touch.
Vitamin B12 (Cobalmin) is a water soluble vitamin and plays a key role in the normal functioning of the brain and nervous system, and in the formation of red blood cells. Vitamin B12 deficiency can occur if the body does not absorb enough vitamin B12 from the gastrointestinal tract or when there is not enough dietary intake of the vitamin. One common cause of deficiency is as a result of pernicious anaemia which is an autoimmune disorder that results in inflammation and damage to the stomach lining, and loss of parietal cells. The parietal cells produce intrinsic factor, a protein needed for absorption of Vitamin B12 in the gut.
The probe was cleaned with distilled water and dried before placing into the unknown solution. The solution was .500+-.0005g of the unknown compound dissolved in 20+-0.5mL of water contained in a 40 mL beaker. A 10 mL graduated cylinder was used to measure accurately. The conductivity of the unknown compound was recorded and then the probe was removed and cleaned. Next, the probe was placed in potassium nitrate solution.
Jaax et al., 1996; Ryabchikova et al., 1999). Therefore, the impairment of the liver may explain the overall pathogenesis as hemorrhagic tendencies in certain cases related to decreased synthesis of coagulation factors and other plasma proteins as a result of severe hepatocellular necrosis. Impairment of