We then slowly added 25ml of chilled deionised water to the filtrate to initiate crystallization by using a measuring cylinder and a dropping pipette, once we had done this we left it for about 10 minutes to allow crystallization at room temperature. We then weighed a filter paper which we will use later in the experiment. We then collected the crystallized acetylsalicylic acid by vacuum filtration in a Buchner funnel and washed the product with a little ice-cold water. We then pre-weighed a clean, empty watch glass and labelled it with our initials and the date, we did this do we could easily identify that it was ours when we go to weigh it with the crystals on. We
32) Deionized water is injected into the right beaker. 33) A sixty-minute timer was started to see how the 9 Urea (mM) solvent diffuses through the 100 (MWCO) Dialysis Membrane. 34) The outcome is cataloged. 35) The 100 (MWCO) Dialysis Membrane was removed from between the beakers and put back into the original membrane container. 36) The left and right beaker are emptied and clean to begin the next trial.
After the 30 minutes is done, the tests tubes are then immersed in a 100 degrees Celsius methanol water bath for 15 minutes. Once the samples become frozen, put in a lyophilizer at a temperature of -109 degrees Celsius. The samples are allowed to completely dry. After 6 hours remove from the lyophilizer. Acetonitrile at a PH of 7 (neutral) is added to each of the test tube samples.
In the donor compartment, proliposomal formulation and control (drug suspended in sodium CMC) equivalent to 10mg of KTZ were placed separately. 30% v/v acetonitrile containing phosphate buffer saline (pH 7.4) was taken as receptor medium and kept under constant stirring upto 24 h. In order to avoid evaporation of the contents, donor compartment and sampling port are covered with aluminium foil. 500 µL of aliquots are drawn at predetermined time intervals and equal volumes have been replaced so as to maintain receptor phase volume. All the samples withdrawn were estimated for drug content using HPLC and the data was fitted into mathematical equations (zero order, first order and Higuchi models) (Szuts et al., 2010) to derive the kinetics and mechanism of drug release from proliposomal gel
A control extract is prepared (5ml of DAE) to a test tube, which is then placed in boiling waterbath for 10minutes, after 10minutes remove the control extract and leave it to cool at room temperature. In order to determine the amylase activity, one drop of iodine is dropped into 21 labelled wells on the ceramic test plates. A reaction mixture is prepared, 5ml of buffer and 1ml of 0.5% starch solution to a test tube. Extract one drop from the reaction mixture to the well labelled T. Turning blue-black indicating the presence of starch in the reaction mixture. Add 1 ml of diluted amylase extract to the reaction mixture.
The drop rate was adjusted to 1 to 2 drops/second. 10.0 mL of the NaOH solution was allowed to drip away into a waste beaker. The exact volume of the sodium hydroxide solution used was determined. A clean 250-mL beaker was taken and around 0.3 to 0.5 g of potassium acid phthalate was weighed into it. 50 mL of distilled water was approximately added to this 250 mL beaker and gently swirled so that the solid (potassium acid phthalate) got fully dissolved into the water.
Briefly, the cartridges were preconditioned by flushing with 2 mL of methanol and 1 mL of HPLC water. Separately, 50 µL of plasma sample plus 100 µL of an 85% phosphoric acid:water mixture (1:10) and 10 µL of internal standard solution (diclofenac at 100 µg/mL) were vortex mixeding. Then, samples were loaded into the cartridge and allowed to stand for 5 min, washed with 0.6 mL of a water:methanol mixture (95:5. v/v) and then dried under vacuum. The (S)-ketoprofen was eluted with 1 mL of an acetonitrile:methanol mixture (50:50, v/v) at a flow rate of 1 mL/min. The eluate was evaporated to dryness in a water bath at 37.0 ± 0.5 ᵒC under a gentle stream of nitrogen.
This diluted solution will be used in the assay as duplicate samples. Then, 1.0mL of standard glycine solution containing (7.5mg/mL) was diluted to 100mL with water using a volumetric flask. This solution contains 1.0µmole/mL of glycine. 8 tubes were set up according to the following protocol and 2.0mL of ninhydrin reagent was then added to each of the 8 tubes and were placed in a boiling water bath for 20 minutes. After 20 minutes, the tubes from the bath was carefully removed, cooled in a beaker of cold water, then 8.0mL of 50% ethanol was added and mixed well.
A number of 11 two ml microcentrifuge tubes were assembled and was labeled as: Tubes 1a-c through 3a-c: Product Extract Dilution 1 through 3 (repeat three times for 9 tubes), Tube 4: Positive control, α-tocopherol and Tube 5: Negative control, solvent only. α-tocopherol, also known as the Vitamin E was prepared as the postive control. A concentration of 10 mg/ml was obtained by the stock solution (in ethanol, it must be kept in the refrigerator and shielded from light).10 µl from the Vitamin E stock was removed and transferred in a labeled eppendorf, at cool temperature and protected from light. 40 µl of 100% ethanol was added to the positive control tube. 50 µl of prepared extract was added at 2 mg/ml to Tube 1 a-c ( 100 µg of overall extract).
A. INTRODUCTION DESCRIPTION Metronidazole is 1-(2-hydroxyethyl)-2-methyl-5-nitroimidazole B.P. It appears as a white to brownish cream crystalline substance with melting point 159-162C. Solubility in water at 20C is 1g/100mL; in ethyl alcohol, 0.5g/100mL; in chloroform, 0.4g/100mL; slightly soluble in ether and soluble in dilute acids. When reconstituted as Metronidazole IV for Infusion, it has a pH of between 4.8 and 5.2.