Chitosan is a product obtained from chitin, which has been found in a wide range of natural resources including crustaceans [12, 21, 22] and fungi [11, 18, 23]. The production of chitosan from chitin can be performed by distinct methods[24], but the most common is the process called deacetylation[11, 23] which consists in the removal of the acetyl group and is usually performed with concentrated NaOH at high temperatures[16, 25].
The characteristics of chitosan that may affect its sorption properties should be explain in order to understand the values and limitations of the chitosan used in this experiment. These include the degree of deacetylation, the structural condition and the crystallinity.
The degree of deacetylation has to be greater
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Chemistry text books explain that because of its small size, copper ions attract ligands, which are species that are rich in electrons and can form co-ordinate covalent bonds (can donate electrons) to form complex ions[28].
When the copper ion is joined to one or more ligands, a coordination complex is formed where the ligands act as electron donors, and the central atom of copper acts as an electron-pair acceptor. This complex has a structure called coordination sphere[2], with four ligands attached to the central atom.
Adsorption is a process where one or more components (adsorbates) are attracted and bonded to the surface of a solid (adsorbent) with which they are in contact[29]. Chitosan is effective in the adsorption of metal ions due to its vast number of amine groups (-NH2) [12, 14, 15], which are the main active sites[11, 12, 14, 18, 21, 30] and the hydroxyl (-OH) groups, which contribute to a lesser extent[11, 14, 18, 21, 30]. Possible adsorption mechanisms of metal ion uptake by chitosan include the formation of ternary complexes, electrostatic repulsion and chelation [14, 31]. The formation of ternary complexes is the mechanism for the adsorption of alkaline and alkaline-earth ions[29], and the electrostatic repulsion occurs in systems concerning chitosan and anions[29], therefore those mechanism
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This model is less preferred by scholars, who do not usually find evidence of its existence such as data from colorimeters or IV spectrometers. While there is no general consensus for the chelation of copper by chitosan in the actuality, the balance seems to be titled in favour of the pendant model. However, scholars suggest that chelation is extremely dependant on factors such as contact time, temperature, pH and adsorbent dose [36, 37], therefore it is conceivable that this type of chelation occurs in some specific conditions, but probably not as commonly as the pendant
The mixture was combined with saturated sodium chloride, and the aqueous layer, containing alcohol, some acid, and water, was discarded. The organic layer was then dried with granular anhydrous sodium sulfate; this drying agent is used to absorb any water in a solution and should thus, result in a colorless solution. The final product was collected; it was mostly clear, though it has a pale yellow tint. Data Table 2 shows the results and calculations that were gathered after the completion of this experiment. No errors had occurred during the course of the experiment, which is testified by the fairly, high yield of
The purpose of this lab was to to cycle solid copper through a series of chemical forms and return it to its original form. A specific quantity of copper undergo many types of reactions and went through its whole cycle, then returned to its solid copper to be weighted. We observed 5 chemical reactions involving copper which are: Redox reaction (which includes all chemical reactions in which atoms have their oxidation state changed), double displacement reaction, precipitation reaction, decomposition reaction, and single displacement reaction.
== == I completed a table to show my results, here is the table: Table 1. Results of different changes of substances Part A Copper (II) Sulfate and Water Reactant description Water (reactant): Color: Colorless Transparency:
Since the discovery of cisplatin, thousands of platinum complexes were evaluated, but only five were approved. Consequently, more than 10000 compound need to be screened so as to get a novel and more effective anticancer drug than cisplatin with the aid of inorganic or coordination chemistry. Solubility, reactivity, electronic and steric effects, and the configuration of metal complexes can be controlled by modifying the metal to other transition metal such as Pd and Ni or the ligand around the metal atom which has been reported that both the metal and the ligand can determine the biological activity. Hopefully we can find more efficient drugs that may contain much less side effects than cisplatin, as well as solve the problem of overcoming drug resistance of some cancers to cisplatin.
Copper is a transition metal and one unique property of transition metals is to create different types colored compounds . Copper(II) sulfate, also known as cupric sulfate or copper sulphate, is the chemical compound with the chemical formula CuSO4. Existing as a gray white powered in anhydrous form however more commonly encountered salt in the laboratory is pentahydrate or (CuSO4·5H2O ) is bright blue in powdered form . In my experiment I used this bright blue powder by dissolving the powder in water leading to a exothermic reaction the exothermic reaction to create an aquo complex [Cu(H2O)6]2 .
This happens at the cathode: Cu2+ +2e- = Cu And oxygen is produced at the anode. Increasing the concentration is more affective than increasing the voltage but in order to gain more copper, you will need the highest
Thickett, Geoffrey. Chemistry 2: HSC course. N/A ed. Vol. 1. Milton: John Wiley & Sons Australia, 2006. 94-108. 1 vols. Print.
If the distance between the two electrodes is smaller, the copper ions need less energy to flow from the anode to the cathode
== § Test tubes X 11 § 0.10 molar dm -3 Copper (II) Sulphate solution § distilled water § egg albumen from 3 eggs. § Syringe X 12 § colorimeter § tripod § 100ml beaker § Bunsen burner § test tube holder § safety glasses § gloves § test tube pen § test tube method = == = =
The chitosan nanoparticles used widely as a drug delivery systems last few years. In the present study the Echis carinataus snake venom loaded chitosan nanoparticles were prepared based on ionic gelation of tripolyphosphate and chitosan.. The nanoparticles physicochemical characteristics , stability and biological activity of encapsulated venom were studied . The particles were spherical in shape and the tripolyphosphoric groups of TPP were linked to the ammonium groups of chitosan. Optimum particle size of chitosan and venom loaded nanoparticles were 89 and 116 nm, respectively. Optimum loading capacity and loading efficiency obtained by 500 µg/ml concentration of venom . The biological activity of venom remained intact during nanparticulation and showed no considerable reduction in stability analysis. Our results suggested that Chitosan nanoparticles, which prepared in this work possibly, could be used as an alternative for traditional adjuvants.
V. Amarnath, D. C. Anthony, K. Amarnath, W. M. Valentine, L. A. Wetterau, D. G. J. Org. Chem. 1991, 56, p. 6924-6931.
(Khan): further states, here L are the Ligand and which is formed via the complete replacement of water molecules by other ligands can occur till the formation of the MLn complex. “n” is the coordination number of the metal ion and represents the maximum number of monodentate ligands which can be bound to it [8]
Secondly, the ionic bond involves transfer the electrons to achieve a completely filled outer shell. This type of bond occurs between metals and nonmetals. When the metals want to lose their electron, the nonmetals want to gain to achieve noble gas configuration. The crystals which have this type of bond, have hardness and specific gravity moderately. They have also high melting point and they are poor conductors. Bonding in most of the minerals is largely ionic.
It forms from the outer skeleton of insects and crusta-ceans like lobster, crabs, and shrimp [26]. In chitin, the compound structure which is like cel-lulose, every monomer having one hydroxyl grouping which is substituted with an acetyl amine gathering (Figure 2). The extraction of chitin followed by a deproteinization (removal of proteins) which involves the removal of an acid calcium carbonate (demineralization), done mostly through the hot reaction with HCl, HNO3 etc., This step generally achieved by alkaline treatments (e.g. With NaOH) [27]. Chitin has an extremely well-arranged crystalline structure in its extracted crude form which is shining, strong and quite tough. But it has low reactivity and poor
It is split into high and low energy orbitals, this energy difference is referred to as and this delta is a property of both the ligand and the metal.