Essays on Absorbance

Introduction:

Nanobiotechnology serves as an imperative technique in the development of clean, nontoxic, and eco-friendly procedures for the synthesis and congregation of metal NPs having the intrinsic ability to reduce metals by specific metabolic pathways. Silver nanoparticles are particularly interesting nanoscale systems due to the ease with which they can be synthesised and modified chemically. Synthesis of silver nanoparticles has been widely researched due to their interesting size and shape-dependent properties [26]. These novel properties can be tailored by controlling their size, shape, composition, structure and crystallinity. Due to their size features and advantages over available anti-microbial properties, chemical imaging ...

Introduction

Spectrophotometry is one of the most common and efficient means of chemical analysis currently used in estimating the concentration of some chemicals. The technique exploits the radiation absorption property of various chemical substances in determining their concentrations. Spectrophotometry is based on Beer-Lambert Law. Beer-Lambert Law is the linear relationship between the absorbance and concentration of an absorbing species (Nair, 2010; Burrows et al., 2013). The mathematical expression of Beer-Lambert Law is shown in equation1 below: A=aλ*b*c Equation 1 In the equation 1 shown above, A represents the measured absorbance, a is the absorptivity coefficient which depends on ...

Iridium organometallic complexes

Introduction Iridium organometallic complexes are applied as catalysts, light-emitting diodes, dye-sensitized solar cells, and luminescent agents for cells imaging.1 Due to the wide application area, the scientists perform research on preparation, characterization and physical and chemical properties of iridium organometallic complexes.

The oxidation state in complex compound refers to the charge of the metal, which it would have in a simple ionic compound. The configuration of d-orbitals (dn) indicates the number of valence electrons in free metal of the same oxidation state. The iridium electronic configuration is [Xe] 4f145d76s2, yet the s-electrons transfer to d-orbital to form 5d9. The ...

Abstract

The research is dedicated to studies of activated carbons performance in the wastewater treatment process of dye removal. The experiment was performed to assess the efficiency of the commercial activated carbons (F100, F600, F820, SGL 8×30, CAL, AP4-60, OLC12×30) in adsorption process for Dylon Burlesque Red removal. The effect of pH, type of activated carbon, dye, contact time, and salinity was studied. The experiments were performed by measuring the absorbances of the solutions before and after contact with the activated carbon. The absorbance was evaluated with UV-vis spectrometry. The adsorption of the dye took place on all ...

Chapter 1

Introduction

XX century was characterized with the significant technological progress, which has improved the life of people. Numerous products and services became available, labor and domestic life became easier and more comfortable. However, waste problem is the other side of the technological progress. The solid, liquid and gas waste are formed, and thus land, natural water and air quality degrade. Therefore, in XXI century the research efforts are dedicated to development of methods for sustainable use of water, gas, and solid resources. Wastewater polluted with dye residuals originate from textile, leather and food industry. These industries produce goods that ...

Introduction

The kinetic characteristics are important for the design of chemical engineering processes. They allow assessing the time required for the reaction and choosing the temperature range suitable for the reaction. The reaction path is observed by measurments the transmittance of the Crystal Violet solution that reacts with sodium hydroxide. The concentration, and the color of the solution changes with the reaction flow, and this is measured by the spectrophotometer.

The data are plotted as concentration - time and logarithm concentration time, and the reaction rate is:

Rate = [Crystal Violet] [Sodium Hydroxide]. Using the excess concentration of one of the reagents, the reaction rate with respect to the other reagent is found from logarithmic plot (Rahul & Chakrabarti ...

Based on the initial symptoms, the patient most likely suffers from hypothyroidism or low thyroid hormone disorder. Further clinical tests and an examination of the family’s medical history reveals that the particular disorder could be Hashimoto’s disease; also called Hashimoto thyroiditis. Hashimoto thyroiditis is classified as an autoimmune disease. In autoimmune disease, one's immune system attacks the body’s tissue specifically the thyroid gland (Skugor & Wilder, 2006, p.2). By attacking the thyroid gland, the disease reduces the gland’s ability to produce thyroid hormones of substantial quantity. This condition leads to hypothyroidism. Thyroid hormone deficiency presents with ...

I. Introduction Advances in recombinant DNA technology and bioinformatics-based data analysis have driven the explosion of structural biology in the last two decades (Kelly, Jess, and Price 119). This has resulted to the identification of at least 2000 proteins annually and a growing need in performing structural studies in these new proteins. The current trend involves the concern of analyzing protein structures close to its natural conditions (and other conditions) and of measuring their rates of structural changes, an essential factor in their biological functions. The technique of circular dichroism (CD) has gained an increasing popularity in addressing these ...

Introduction

There are environmental chemical processes which require light to react. These processes are called photochemical reactions. Photochemical reaction is commonly initiated due to the absorption of solar energy or light. When molecules absorb energy in the form of light, the atoms are converted in a transient excited state (Larson & Weber, 1994). This transition state or excited has completely different physical and chemical properties with the initial state of the molecule. The excited states also have more tendencies to react since they are considered stronger acids and stronger reductants that the initial state of the molecule. The excited state of ...

The objective of this experiment was to prepare Beer-Lambert calibration curves for different forms of nitrogen and to determine the concentration of nitrate, nitrite, and ammonia ions in different water samples from the Biscayne Bay.

Introduction

Nitrogen is the most abundant element in the Earth atmosphere. In is not surprising that it is one of the most crucial elements not only to human life but all life on our planet. The chemistry of nitrogen is rather diverse because it can exist in different oxidation levels – from +3 to -5. Due to its large impact on the biosphere, the circulation of ...

Part 1. Absorbance Spectra

The SpectroVis spectrophotometer cable was plugged into the LabQuest. The spectrophotometer was then calibrated by selecting the corresponding command from the menu. After the lamp has been warmed up, the cuvette filled with deionized water was put into the device, and the calibration was finished. Then, the cuvette with the red solution was wiped and inserted into the sample compartment with its clear face facing the arrow. The spectrum of the solution was obtained (using Start and Stop buttons). The results were saved and hidden using the File Cabinet. The cuvette with the red solution was removed from the ...

Abstract

Human activities have a significant influence on marine life. Pollutants from landfills, dumps, mines, farms, etc. can pollute the ocean and later through the food chain cause harm to all land animals and humans as well. Protein is a very important structural component of an organism. Using protein for energy is an inefficient form of metabolism and in the long run detrimental to the organism. A significant low level of protein content was noticed in Mytilus californianus or (mussels) obtained from the polluted environment when compared to the tissue of Mytilus californianus obtained from pristine environment. Organism that are ...

List of Figures

Figure 1 Protein concentrations under the four conditions 7 Figure 2 Protein standard curve via Bradford assay at 595 nm 13 Figure 3 Protein standard curve via BCA assay at 490 nm 15

List of Tables

Introduction Proteins are essential for life and we depend on them to interact with cellular molecules in order to live (Pace et al. 2004). Increasing the knowledge about protein solubility is significant for biological studies because increased protein concentrations enhance studies of cellular structures and functions (Golovanov, Hautbergue, Wilson, & Lian, 2004). Accurate protein quantization is also necessary for cellular studies (Johnson, 2012). The environmental conditions of ...

Introduction

Knowledge of how rapidly reaction proceeds is among the most important for practice in chemistry and chemical engineering. We often use casual descriptions of reaction rate such as “slow” or “fast” in our lives, however, such information can be scarcely enough for practical and industrial applications, such as running a chemical plant, for example. While there is a huge spectrum of the reaction rates that are present in nature – from the extremely slow steel oxidation to extremely rapid gas combustion, the quantitative measure is needed to compare them practically. For a general reaction in solution:

the kinetic rate expression ...

Verification of the Beer-Lambert Law for Solutions of Copper Sulphate and Determination of the Concentration of a Given Solution of Copper Sulphate

Introduction

The determination of elements concentrations in water media is an important task in industry, medicine, and environmental protection. The main requirements are accuracy, simplicity of operations, speed and cost of the analysis (Hunt 1995). The spectroscopic analysis is widely applied for routine measurements and research needs (Lindon 2010). The experiment is dedicated to determination of copper sulphate in water using the molecular absorption (Kenkel 2003). The first stage of the experiment performs absorbance measurements of the solutions ...

Introduction

In addition to their important roles in natural environ- ments, microbial enzymes can be highly specific in their activity and thus are increasingly useful in industrial applications. Enzymes from aquatic bacteria adapted to moderate and high temperatures have already figured in a variety of applications, including polymerase chain reac- tion (PCR), laundry detergents, protein recovery and organic synthesis (e.g. Mullis and Faloona, 1987; Adams and Kelly, 1995). Although enzymes with optimal activity at cold temperatures have been understudied compared with their heat-stable counterparts, increasing attention is being paid to cold-active enzymes as potential applica- tions are revealed Enzymes are ...

Investigating how light intensity will affect the rate of photosynthesis, with the help of DCPIP, in Spinach leaves.

The aim of this experiment is to find out how the rate of change of light intensity affect the photosynthesis in spinach leaves. Successful farming of food crops is very essential for both the nutritional and financial health of a nation. Governments of almost every nation invest land and labour to crop farming, as much as is possible, keeping in mind the other needs of a country. But, however, due to many reasons the maximum crop yield possible is not always achieved. For the production of a healthy crop certain conditions are necessary. The primary among these conditions are ...

Abstract

This lab report discusses the Cellular Location of Metabolic Enzymes. Regarding methodology, the experiment was conducted in three sessions during the first session liver homogenate and cell functions were prepared. The first session was carried out by homogenizing the liver in an isotonic media. The Maltase and lactate dehydrogenase were determined in the second session, and protein concentrations were estimated in the third session. The Maltase dehydrogenase (MDH) and Lactase dehydrogenase (LDH) were used to catalyze the reactions in session two. The biuret reaction was used to estimate the protein in the last session. The relationship between absorbance at ...

Introduction

Spectrophotometry refers to a method that is employed in the determination of the amount of light that is absorbed by a chemical substance. In chemistry, the term spectrophotometry refers to the determination of the reflection or transmission characteristics quantitatively material through a function of wavelength (NIST, 2012). The spectrophotometry analysis is carried out through the light intensity determination as a beam of light passes through a tube containing the sample solution. The process of analyzing solution concentration using spectrophotometer utilizes the fact that light possesses a dual nature. This is where the light may exist either as particle or as a wave (Keller, 2003). Basically, ...

1. Compare and contrast organic, inorganic and solid phase approaches for DNA isolation

Organic isolation takes place after the DNA has been released from the cell and a further purification is to be conducted. The purification is done in order to remove the contaminating proteins, lipids, carbohydrates and cell debris. Organic isolation makes use of a combination of high salt, low pH and an organic mixture of phenol and chloroform. The mixture dissolves hydrophobic contaminants and then strips away most of the DNA associated proteins. The DNA precipitate in this method is collected by centrifugation. The DNA pellet is then dissolved in rehydration buffer. Inorganic isolation method is used in cases that do not ...

Aim: To measure the partition coefficient values of sulphamidine and acetylsulphamidine present in water/octanol solution at different pH.

Abstract: After measuring the pH of the buffer solution, two lots of eight bottles were prepared. 5ml of drug and 5 ml of buffer solution were added to each bottle and shaken for 30 minutes. Absorbance was then of the solutions in the bottles was then determined. Introduction: Partition coefficient gives a measure of how a substance distributes in two different phase at equilibrium. Partition coefficient is utile in estimating the distribution of the drug within the body. There are two types ...

Serine protease autotransporters of enterobacteriaceae (SPATEs) are particularly secreted by gram-negative enteric bacteria via autotransporter pathway (Rawlings, 3093). SPATEs are a wide family of proteases that are secreted particularly by Escherichia coli and Shigella flexneri. Shigella has several SPATEs including SigA, SepA, and Pic (Leonard, 1176). These proteases show two different proteolytic activities. Firstly, an intramolecular cleavage is initiated by a C-terminal catalytic site. This triggers the release of the N-terminal domain of the proteins into the medium surrounding the cell. Secondly, the N-terminal portions themselves are proteases with each containing a conical serine- protease catalytic portion. These secreted portions have various ...

Forensic investigations have gained widespread application by law enforcement agencies during the analysis of a crime (Tewari and Ravikumar 2000). Forensic experts have a tough task because they have to use samples collected from a crime scene to reveal the culprits. In this case, the investigator has to determine which of the two companies (A or B) is responsible for the pollution that was reported. The samples that were collected have been analyzed using Fourier Transform Infrared (FTIR) spectroscopy. This form of spectroscopy is employed to produce an infrared spectrum of not only photoconductivity and emission, but also absorption of a substance ...

Abstract

All cells in a living organism require energy to drive various cellular activities such as transport of molecules and movement among others. The rate of cellular respiration may be affected by the substrate concentration, pH level and enzyme concentration among other factors. This experiment aimed to study the rate of cellular respiration in isolated mitochondria under different conditions. It was hypothesized that if the concentration of the substrate is increased then there will be an increase in the rate of cellular respiration. Mitochondrial suspension was used as the source of succinate that was used as the substrate. The level of ...

Aim

The experiment aims to study the effect of substrate concentration on the activity of polyphenol oxidase (PPO) from banana extracts using spectrophotometric techniques.

Introduction

An enzyme refers to a molecule that is protein in nature and works as a biological catalyst. The enzyme possesses three major characteristics. The first characteristic is that they act to increase the rate at which a given reaction takes place. This enables most cellular reactions to take place at up to million times faster compared to their rate in the absence of an enzyme. Secondly, most enzymes act specifically on a single reactant known as a substrate to produce the ...

Abstract. Oxidation of ethanol is carried out by the oxidizing agent, potassium dichromate. The oxidizing agent undergoes a color change followed by the completion of the reaction. This change of color is utilized to measure the absorbance of the solution. The concentration of the unknown ethanol sample is calculated by plotting an absorbance vs concentration graph of the standard solutions.

Module and group

Lab class completed - Introduction The aim of the experiment is to determine the concentration of ethanol by calorimetric determination method. The concentration of ethanol is measured following its oxidation with potassium dichromate. Potassium dichromate (K2Cr2O7) undergoes reduction, ...

Abstract

Enzymes are the large biological molecules that play the role of metabolic processes responsible for maintaining the human life. They have the ability of high selectivity, as natural catalysts. They accelerate both the specifity and rate of metabolic processes, from food digestion and DNA synthesis. Most scientific enzymes are proteins in nature, even though some RNA molecules which are catalytic have been studied. The structures of enzymes normally adopt a three dimensional structure, and in order to assists in catalysis, it may employ the organic and inorganic forms. This experiment is meant to describe the properties and characteristics of enzymes ...

(City, State)

Abstract

Reactions taking place in a biological system are usually catalyzed by enzymes. One of these enzymes is the cellobiase, which is works to degrade cellobiose into glucose monosaccharides. Just like any other enzyme, cellobiase works under very specific conditions and alteration of these factors may result in a reduction, in its activity. The experiment was done with an aim of studying the cellobiase in terms of its reaction rate and how factors such as temperature, pH concentration of enzyme and the substrate affect the rate of cellobiase activity. It was determined that cellobiase has an initial rate of a reaction ...

(City, State)

Abstract

Cellobiase is an enzyme that is involved in hydrolyzing the products of the exocellulase (cellobiose) to form individual monosaccharides. The process breaking down cellobiose is a natural process and helps most organisms produce glucose for use as a source of food. This experiment aimed to study the cellobiase by determining its rate of reaction and effects pH, temperature, concentration of the substrate or enzyme on the rate of reaction. The initial rate of a reaction catalyzed by cellobiase enzyme is 11.25nmole/Minute with the optimum temperature being 37OC and the optimum pH was pH5. The activity of the enzyme is also ...

Introduction

One of the most important part of protein assay is the determination of protein concentration. There are diverse methods used for protein concentration determination, but the most widely used are the spectroscopic methods of analysis or spectroscopy. Spectroscopy usually involves the determination between the correlations of the degree of interaction of light with the analyte, which is the proteins in this particular experiment. There are different types light to analyte interactions and one of these is the absorbance of light or electromagnetic radiation by the analyte. This type of spectrometry is called absorbance spectrometry.

Principle involved in absorbance spectrometry and spectrometers

The majority of substances absorb ...

Lab Report: Ethanol Determination Experiment

Objective: “To Determine the Ethanol content in several beverages using the enzyme alcohol dehydrogenase.”

The Chemistry behind this experiment is simple enough to understand. In the reaction carried out in the experiment, Nicotinamide Adenine Dinucleotide (NADH) is formed which can be analyzed quantitatively to find the concentration of Ethanol. The reaction involves oxidation of Ethanol to Acetaldehyde. This oxidation takes place with concomitant reduction of NAD+ to NADH. This formation of NADH can be seen in the Δ absorption at 340 nm micro level. At this wavelength, the reduced co enzyme absorbs at a very fast rate than the oxidized one, ...

Introduction

The major experiments that are conducted in the determination of enzyme kinetics are those that vary the amount of concentration in order to measure the enzyme velocity . The aim of such experiments is to determine the Km or the amount of the substrate that gives half the enzyme velocity, as well as the Vmax, which is the maximum velocity attained by the enzyme . In addition, the enzyme kinetics may be presented graphically using the Eadie–Hofstee diagram. The diagram made by plotting the rate of reaction as a function of the ratio between rate and concentration of the substrate as ...

Introduction

Concentration refers to the quantity of a given solute or analyte that is present in a given quantity of solution. Measuring the quantity of a solute in a solution requires the use of different techniques. One of these methods employs use of a standard whose concentration is known and an instrument to detect the solute. Standards refer to set of mixtures whose solute and solvent have been accurately weighed or measured to give the correct concentration. The absorbance of the standards can then be measured using a spectrophotometer. A graph indicating the relationship existing between the solute concentration of the standards and their absorbance can ...

The absorbance measured using standard samples were as shown in Table 1 below.

The absorbance measured in determining trypsin rate of activity in the absence of inhibitor was recorded in Table 2 below.

The absorbance measured in the determination of trypsin in the presence of inhibitor was recorded in Table 3 below.

The results of absorbance of the different standard samples were used to plot a graph of absorbance against p-nitroaniline concentration as shown in Figure 1 below. Figure 1: A standard curve on the relationship between absorbance and p-nitroaniline concentration Figure 2: Relationship between absorbance and p-nitroaniline concentration Figure 3: Relationship between rate of reaction and p-nitroaniline concentration in the presence of an inhibitor

Reciprocal of the data used to plot Figure 2 and 3 was calculated and used to plot Figure 4 and 5 respectively.

Figure 4: Lineweaver-Burk plot in the absence of inhibitor

Determination of Vmax and Km was conducted as follows:

y = -302.55x + 514.35 1V = ...

Abstract

The purpose of the study is to identify the highest concentration of starch and reducing sugars in a sample of five chosen fruits, namely watermelon, red grapes, green grapes, pineapple and orange. This study is important, since it indicates which of the above fruits would give the most energy as carbohydrates. Our hypothesis is that red grapes might have the highest glucose and starch concentration. We base this on the taste of all five samples, out of which red grape samples were the sweetest. The samples were then analyzed using two assays, Benedicts test as well as Acidic Iodine. Three ...

AFFIDAVIT OF [NAME] [DATE]

[on separate page] I [#say on oath #affirm]: I am currently employed as an Environmental Forensic Scientist with the New South Wales Government. I have held this position since 2002. I obtained a Bachelor of Science (Forensic Science) degree from the University of Western Sydney in 2001. I have read, understand and will abide by the Expert Witness Code of Conduct. I was requested by [requester] to determine the composition of the material present in the environment, the source of this material and the level of environmental harm associated with this material.

Sample submission

On the ...

Abstract

This research paper will discuss the significant contribution of DNA fingerprinting in the criminal justice system for being able to provide a reliable basis for conviction. DNA fingerprint analysis is referred as an accurate indicator to determine the guilt and innocence of an accused. The history, importance and various DNA fingerprinting techniques shall be discussed. In addition, DNA fingerprinting is considered as more superior than other forensic science methods since the technology has improved over time. DNA fingerprinting has allowed the test of smaller amounts of material, faster testing procedures and more conclusive results. Finger ridge analysis is science and ...

Introduction

How does the presence of ionic material affect a CMC? Amphiphilic surfactants have both polar and non-polar parts in their molecules. Whenever their concentration surpasses the crtitcal micelle concentration (CMC), surfactants molecules organize themselves in a special structures and form micelles. Micelles in aqueous environment are organized in the way that charged hydrophilic ‘head’ groups of surfactant molecules closer to the surface of a micelle and exposed to water. Whereas, hydrophobic ‘tails’ are directed inside a micelle to avoid contact with water molecules. There is electrostatic repulsion between charged head groups of the surfactant molecules. Therefore, the molecules tend to form a structure ...

The natural soil contains lots of microorganisms that are sufficient enough to naturally produce nutrients required for agricultural activities and benefit the plants; moreover, that improves the quality and quantity of the yield produce. In a situation where the soil fertility is deteriorated, natural and organic fertilizer should be added as they provide all the necessary nutrients required by the living microorganisms and the plants (Traina & Laperche, 1999). Artificially developed fertilizers are rich in nutrients that boost the yield quality and quantity but should be controllably used as they might kill all the microorganism transforming the productive soil into sand. ...

Introduction

Biological reactions are those reactions that are involved in various activities, in the body including energy production. Reactions that produce energy are called exergonic reactions while those that use energy are called endergonic reactions. Enzymes enable chemical reactions to take place within a living system most of which are under a homeostatic constraint. In these reactions, enzymes function as a catalyst by lowering the activation energy necessary in a reaction (Cooper, 2000). Enzymes bring the reactants involved in a reaction closer together weakening the chemical bonds and this enable the reactions to occur faster compared to reactions that have no enzyme (Farabee, 2010). ...

Abstract

Enzymes are biological catalysts and work by speeding up the rate of chemical reactions. The factors that affect enzyme activity include enzyme concentration, temperature, pH, and the substrate concentration. This experiment aimed to determine the effect of lemon juice, which is acidic on the activity of catechol oxidase enzyme. According to the results, high acidity inactivates the catechol oxidase enzyme. The optimum pH level for catechol oxidase enzyme can, therefore, be said to be pH 6.

Introduction

Enzymes are biological catalysts and work by speeding up the rate of chemical reactions. The enzymes achieve this by reducing the amount of ...

C1=0.002M (SCN concentration) [Fe(SCN)2+] will be the same

V1 – volume of SCN solution (5, 7, 9, 11, 13, 15 ml)

V2=100ml (total volume of solution) That is how we obtain data ([Fe(SCN)2+]) for calibration curve. It is incorrect to multiple absorbance on volume for finding [Fe(SCN)2+]. Use abovementioned formula. When we built calibration curve in Excel we used function “Find trend line” on the diagram and click at the option “Show equation on the diagram” The obtained equation is y=0.0003*x-0.000009. A1=0.002*0/100=0M A2=0.002*5/100=0.0001M A3=0.002*7/100=0.00014M A4=0.002*9/100=0.00018M A5=0.002*11/100=0.00022M A6=0.002*13/100=0.00026M A7=0.002*15/100=0.0003M

Determination of the equilibrium constant

2. ...

Day 1 - Cell Culture: At First an LB/amp plate was labeled with initials, the date, the name of the bacterial strain to be used (BL21) and the plasmid (pDHFR). Then 10 uL of reconstituted BL21-pDHFR was pipetted onto an LB/amp plate using sterile tip.The bacteria was streaked into four quadrants of the plate and after this it was covered immediately to avoid contamination. The plate was placed upside down inside the incubator overnight at 37°C and once colonies have grown to ~1 mm in diameter, they may be stored in a sealed bag upside down at 4ºC ...

Abstract

Oxidation is a common problem in olive oil due to its high content of unsaturated fatty acid, this leads to nutritional losses and quality degradation, especially under microwave heating. A number of studies have been done to add natural antioxidants to reduce oxidation. This project examines the possible application of olive leaves to reduce or inhibit olive oil oxidation under microwave heating. Olive leaves were able to increase the total polyphenol content as well as reducing the peroxide value in olive oil. However, the microwave heating caused severe quality degradation (increasing peroxide value and reducing total polyphenol) especially after 10 ...

Lab report discussion and results

Introduction The experiment is aimed at studying about the protein content in the cells and tissues of various organisms and the ways of regulating the growth of some tissues in the body of the animals like in our case we used the rabbit tissues in determining the feasibility of the experiment. The process begins with the ability to look at the process of obtaining the protein from the sample given and how to quantify the amount of protein in such cells.

Method:

Protein extraction The process of protein extraction involves three major processes which must be followed in ...

Introduction

An enzyme is a protein with catalytic properties in biological systems. During an enzymatic reaction, a substance, called the substrate, binds to the active site of the enzyme and is then turned into one or more substance(s), called the product(s). The enzyme itself is not consumed or altered during the reaction. The enzyme activity depends on factors, including pH, temperature, buffer composition, enzyme concentration, substrate concentration, and the presence of inhibitors. Enzymes have an optimal pH at which their activity is maximal. pH determines the ionization states of certain amino acids at the active site that are critical ...

Factors Affecting Enzyme Activity: Lactose Intolerance

Purpose/Hypothesis Lactose is the primary carbohydrate in milk and is commonly known as milk sugar. Lactose comprises of almost 8% of human milk and almost 4% of cow’s milk. Lactose intolerance is a condition in human beings where they lack enzyme lactase since they have trouble in absorbing and digesting lactose. The goal of this experiment is to-: - Learn how substrate concentration, pH and enzyme concentration can affect the enzyme activity in human body.

Data Variable (Procedures)

In this experiments, o-nitrophenyl-β-D-galactopyranoside (ONPG) would be used as a substitute to lactose since it is similar in shape and size and ...

Bader Alanazi

Chemistry 101, Section 7 TA: Hannah 03 / 19 / 2013

Introduction

Light is a form of electromagnetic radiation that also includes microwaves and radio waves. Light energy is made up of photons which shows the properties of a wave in that they oscillate up and down as they move through space (Fritzsch, 2005). The main factor that separates the different types of electromagnetic radiations is that each of them has a different wavelength. For instance, the visible light is comprised of radiation with wavelengths ranging from 400 to 700 nm. The difference in these wavelengths is perceived by the human ...

THE OXIDATION OF OLIVE OIL UNDER MICROWAVE HEATING

Chemistry: Research Proposal Research is proposed to determine whether or not olive leaves are a good source of antioxidants. Reports of experiments to determine the effectiveness of natural plant extracts including olive leaf extracts have found that to be the case. The olive tree (Olea europaea) leaves are attractive because they “contain secoiridoids (oleuropein, ligstrosid, dimethyloleuropein, and oleoside), flavonoids (apigenins, kaempferol, leteolin), as well as phenolic compounds (caffeic acid, tyrosol, hydroxytyrosol).” (Rafiee et al., 2012, p. 1498) High content of antioxidant properties and total phenols have been determined from olive leaf extractions. (Rafiee et al., 2012;) Rafiee (et al., ...

The Metabolism of (PABA) Para-Amino benzoic Acid

Introduction PABA or Para amino benzoic acid is a non proteinous amino acid that occurs naturally. The molecular formula of para- amino benzoic acid is C7H7 NO2; the structure of PABA consists of benzene rings substituted with a carboxyl and an amino group. PABA is a white crystalline molecule that is only sparingly soluble in water. PABA is a very essential nutrient for bacteria PABA functions as an intermediate in the synthesis of folic acid in bacteria The deficiency of PABA does not cause any deficiency diseases in man. Some bacteria in the intestinal tract can synthesise PABA from chorismate. Humans ...

ABSTRACT:

A plasmid DNA is an extra-small circular structure commonly found in bacteria which is capable of replicating by itself in the cell. These are used in genetic engineering as vehicles to carry and make copies of a particular gene which can produce desirable effect. In this report, we discuss the isolation and purification of DNA fromEGFP-LC3 plasmidusing a modified alkaline lysis method and QIAprep spin columns. The concentration of the isolated EGFP-LC3 plasmid DNA was found to be 82.868µg/ml. The ratio of ODs taken at A260nm/A280nm was found to be 5.314 which could be because improper washing step which has ...

1. ABSRACT

The purpose of this experiment was two-fold. Firstly it was to synthesize shape-controllable Copper Oxide (Cu2O) under alkaline conditions by using hydrothermal methodology. Secondly it was to measure and evaluate its application for photocatalytic degradation of direct blue dye 53 also commonly known as Direct Blue 53 or Evans Blue. Materials used for the first step were Cu2O and the two reactants, CuCl2.2H2O and NaOH. The temperature during the hydrothermal process was raised from 80°C to 140°C. Two products were synthesized: a) the Cu2O nanorod and b) a mixture of Cu2O nanorod and Cu2O nanocubes.

Hydrothermal temperature was found to ...

Introduction:

In 1976, Marion Bradford designed the Bradford method that is widely used in measuring the concentration of protein in a solution. When Coomassie Blue is added to a solution containing protein, the solution colour changes from brown to blue and this is attributed to the formation of a protein complex. The concentration levels of protein can therefore be measured by observing the dye color, which fully absorbed at a certain wavelength. The standard curve is used to calculate the concentration of protein because it represents the known BSA (bovine serum albumin) dilution. (Harvard, 2012) A study by Daiet (2008) analysed murinae in ...

Part 1:

Conduct a T-test: a. What is the question you are asking? The question being asked is there is a relationship between the absorbance readings from North Branch Chicago River Site and absorbance readings from North Shore Channel Site. b. What is your null hypothesis? The null hypothesis is that there are no relationship between the absorbance readings from North Branch Chicago River Site and absorbance readings from North Shore Channel Site. c. What is the alternative hypothesis? The alternative hypothesis is that there is a relationship between the absorbance readings from North Branch Chicago River Site ...

Dr. Professor

Paracetamol is crystalline white power with the scientific name N-(4- Hydroxyphenyl) acetamide. The chemical formula is C8H9NO2 and its structure is

Properties

The melting range of paracetamol is 168 to 172oC and its solubility is 14.3g / dm3 of water and ethanol’s 100g / dm3. It is insoluble in ether and dissolves quickly in chloroform. It dissipates uv absorption minimum in aqueous acidic medium at 245 nm and has uv absorption maximum in aqueous alkaline medium.

Assay

Through titration, paracetamol is analyzed using ceric ammonium sulphate. In the titration, Ferroin plays the role of indicator. It is also assayed ...

Introduction:

Coke has become so popular that the drink is replacing healthy beverages in people’s diets around the world. (1, 2) Phosphoric acid is one of the ingredients in the colas that should only be consumed in moderation. The food industry calls the acid used to lower the pH of a food or beverage an acidulant. (3) Phosphoric acid is a food additive under the category of acidulant. (4) It adds “a pleasant tartness to the beverage.” (5) The food industry uses phosphoric acid a lot, “It is added to foods as a preservative, acidifying agent, flavor enhancer, and clarifying agent.” (6) An ...

Abstract

This experiment sort to find an accurate and most viable method that would be used in laboratories to the measurement of iron concentration in aqueous samples. The methodologies that were identified for further analysis included; colorimetric assay (molecular spectroscopy), flame atomic absorption spectroscopy, redox titration (volumetric) and cation exchange chromatography (EMA technique). These methods were analyzed of their advantages and later subjected to a validation test. In the process, a wide range of CRMs were used alongside six other samples that contained unknown iron concentration.

The experiment was thus, geared towards providing answers to statements like; the necessity of quantification of ...

Abstract

Chymotrypsin is a typical digestive enzyme which is mainly used in the digestion of proteins through a process commonly known as proteolysis. The enzyme chymotrypsin often cleaves bonds of peptide amide preferentially where a carboxyl side of that bond is a tryptophan, phenylalanine or tyrosine.

In this experiment, the chymotrypsin molecules were arranged in such a manner that all the enzyme molecules began the catalytic process at the same time. The rate at which the p-nitrophenol was being generated was initially rapid which was then followed by a much slower hydrolysis rate at steady state.

Therefore, the experiment essentially did sort to establish the concentration ...

Ultraviolet-Visible Absorption of a Two-Component Mixture

Introduction. An HPLC instrument was used to determine the UV-Visible Absorption measurements of a cola containing benzoic acid and caffeine. The absorbance wavelength was also measured for an unknown solution. Standards were prepared in order to graph calibration curves (absorbance vs. concentration). Four dilutions were made from the 50 mg/L benzoic acid standard. Four dilutions were made from the 100 mg/L caffeine standard.

Part 1. The UV-VIS spectra for the unknown sample are presented in Figure 1. The spectra showed two peak absorbance at wavelengths 228 nm and 273 nm.

Table 1. Unknown Sample, Peak Absorbance.

Figure 1. UV Absorbance ( ...

Analysis of Unknown using Standard Solutions and HPLC

Part 1.

The data for the construction of the standard curve for caffeine and benzoic acid are presented below.

The graphing of the Caffeine Standard Curve (figure 1) demonstrates an R2 of 0.9898 so this is standard curve is satisfactory for our experiment since 0.9898 approaches 1 closely.

The graphing of the Benzoic Acid Standard Curve shows a better fit as R2 = 0.9989. Each sample measuerment lies on the standard curve.

Part 2.

5 ml of warm Mello Yello was left to sit until the carbonation had released CO2 into the air (outgassing the cola). Then 2 ml of the outgassed cola ...