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  1. Objective: The objective of the hemoglobin test was to measure the concentration of hemoglobin in the blood to assess oxygen-carrying capacity and screen for anemia or polycythemia. 2. Principle: The test was based on converting hemoglobin into a stable form (e.g., cyanmethemoglobin or azide methemoglobin) and measuring its absorbance using a colorimeter or automated analyzer. The color intensity correlated with hemoglobin concentration. 3. Materials: EDTA-anticoagulated blood sample Hemoglobin reagent (e.g., Drabkin’s solution or automated kit) Test tubes or cuvettes Pipettes Colorimeter or hematology analyzer Gloves and lab safety items 4. Procedure (Microscopic/Spectrophotometric): Blood was collected using standard phlebotomy techniques into an EDTA tube. A fixed volume of blood was mixed with hemoglobin reagent. The mixture was allowed to react for a set time (usually 5–10 minutes). Absorbance w...

1. Objective The objective of the test was to detect and identify parasitic ova, cysts, and larvae in stool specimens by concentrating them through sedimentation or flotation techniques. 2. Principle The test was based on the principle of separating parasitic elements from fecal debris using differences in specific gravity. Heavier parasites settled at the bottom (sedimentation), or lighter ones floated at the top (flotation), enhancing detection under a microscope. 3. Materials Stool specimen in clean container Normal saline Ether or ethyl acetate Centrifuge tubes Centrifuge machine Glass slides and coverslips Iodine solution Dropper or pipette Microscope Gloves, lab coat, biohazard disposal bag 4. Procedure (Microscopic) A portion of stool was emulsified in saline and strained through gauze into a centrifuge tube. Ether or ethyl acetate was added to the tube. The tube was capped and shaken vigorously. The sample was centrifuged at ~3000...

1. Objective To concentrate parasitic elements (ova, cysts, and larvae) in a stool sample using the formalin-ether sedimentation technique , enhancing their detection under the microscope. 2. Principle The formalin-ether concentration method uses centrifugation to separate parasites from fecal debris. Formalin fixes and preserves parasitic structures. Ether extracts fats and clears the sample. Upon centrifugation, heavier parasitic elements settle at the bottom ( sediment ) and can be examined microscopically. 3. Materials Fresh stool sample 10% formalin solution Ether (diethyl ether or ethyl acetate) Glass centrifuge tubes (15 mL) Gauze or strainer Applicator sticks Dropper or pipette Centrifuge (capable of ~500 x g) Glass slides and coverslips Microscope (10x and 40x objectives) PPE (gloves, lab coat, mask) Waste container for biohazard and ether 4. Procedure Mix about 1 g of stool with ~7 mL of 10% formalin in a beak...

1. Objective To detect motile trophozoites , cysts , ova , or larvae of intestinal parasites (protozoa and helminths) in a fresh stool sample using light microscopy . 2. Principle In wet mount microscopy , a small amount of stool is mixed with a drop of saline or iodine on a glass slide and covered with a coverslip. Saline (0.85% NaCl) allows observation of motile trophozoites and helminth larvae. Iodine (e.g., Lugol’s iodine) stains protozoan cysts , enhancing visibility of nuclear structures. Microscopy is used under low (10x) and high power (40x) objectives to identify parasites based on morphology and motility . 3. Materials Fresh stool sample Clean glass slides and coverslips Normal saline (0.85% NaCl solution) Iodine solution (Lugol’s iodine) Applicator sticks or toothpicks Dropper or pipette Light microscope (10x and 40x objectives) Gloves and PPE Biohazard waste container 4. Procedure Place a small drop of saline on one...

1. Objective To rapidly detect antigens of Entamoeba histolytica in human stool samples using a lateral flow immunochromatographic test (ICT) , providing a quick diagnosis of amebiasis. 2. Principle The test utilizes monoclonal antibodies specific to E. histolytica antigens, immobilized on a nitrocellulose strip inside a plastic cassette. When stool extract is added, if the E. histolytica antigen is present, it binds to gold-labeled antibodies in the conjugate pad and migrates by capillary action. A visible colored test line forms at the "T" (test) line if the antigen is present. A control line (C) appears in all valid tests to confirm the test worked properly. 3. Materials Entamoeba histolytica rapid test cassette (ICT device) Sample buffer (provided in kit) Stool collection container Dropper or swab stick Timer or stopwatch Gloves and PPE Biohazard disposal container 4. Procedure Collect stool sample in a clean contain...

1. Objective To detect specific antigens of Entamoeba histolytica in stool samples using the Enzyme-Linked Immunosorbent Assay (ELISA) technique, helping to diagnose amebiasis. 2. Principle The test is based on the antigen-antibody interaction . Specific monoclonal antibodies against E. histolytica are coated on a microtiter plate. When a stool sample containing E. histolytica antigen is added, it binds to these antibodies. A secondary enzyme-linked antibody then binds to the complex. After adding a chromogenic substrate, a color change occurs if the antigen is present. The intensity of the color (measured spectrophotometrically) corresponds to the antigen concentration. 3. Materials Stool sample (fresh or preserved) Entamoeba histolytica Antigen ELISA kit: Microtiter plate pre-coated with anti- E. histolytica antibodies Sample diluent Wash buffer Enzyme-conjugated detection antibody Substrate solution (e.g., TMB) Stop solution Positive and n...

1. Objective The objective of the Fecal Fat Test was to detect and quantify the amount of fat excreted in the stool, which helped in diagnosing fat malabsorption conditions such as steatorrhea . 2. Principle The test was based on the principle that fat malabsorption results in excess fat being excreted in the stool. This fat could be detected qualitatively using staining methods (e.g., Sudan III stain) or quantitatively by chemically measuring the amount of fat in stool collected over 72 hours. The fat appeared as orange-red droplets under a microscope when stained. 3. Materials Clean, wide-mouth stool collection container Sudan III stain (or Sudan IV)   Acetic acid (36%) Glass slides and cover slips Applicator sticks Microscope Gloves and PPE Weighing scale (for quantitative test) Solvent (e.g., alcohol) for stain preparation 4. Procedure (Qualitative Method – Sudan III Stain) A small amount of emulsified stool was placed on a clean ...

1. Objective The objective of the Stool for Ova and Parasite (O&P) test was to detect the presence of parasitic organisms, including protozoa (trophozoites and cysts) and helminths (eggs and larvae), in the fecal specimen of a patient with gastrointestinal symptoms. 2. Principle The test was based on the microscopic identification of parasite ova (eggs), cysts, and trophozoites in concentrated or direct wet mount stool preparations. Concentration techniques improved detection by separating parasites from fecal debris. Iodine and saline were used to enhance visibility. 3. Materials Stool collection container Applicator sticks Glass slides and cover slips Normal saline (0.85%) Iodine solution (e.g., Lugol’s iodine) Centrifuge tubes (if using concentration method) Formalin or preservative (for preserved samples) Microscope Gloves Biohazard disposal materials 4. Procedure (Microscopic – Direct Wet Mount Method) A small amount of freshly pa...

  1. Objective The objective of the Fecal Occult Blood Test (FOBT) was to detect hidden (occult) blood in the stool, which was not visible to the naked eye, and served as an early indicator of gastrointestinal bleeding, ulcers, colorectal cancer, or polyps. 2. Principle The test was based on the principle that the presence of blood in the stool could catalyze a chemical reaction. Most commonly, guaiac-based FOBT used the pseudoperoxidase activity of hemoglobin to oxidize guaiac resin in the presence of hydrogen peroxide, producing a blue color change if blood was present. Alternatively, immunochemical tests (iFOBT or FIT) used antibodies to detect human hemoglobin. 3. Materials Stool collection container Guaiac test cards or immunochemical test kits Applicator sticks Hydrogen peroxide reagent (for guaiac method) Gloves Instruction leaflet (for at-home tests) Control solutions (positive/negative, if available) 4. Procedure (Guaiac Method) The patie...

1. Objective The objective of the Arginine Dihydrolase Test was to determine whether the test organism produced the enzyme arginine dihydrolase , which hydrolyzed arginine to ornithine, ammonia, and CO₂ through the arginine dihydrolase pathway. 2. Principle The test was based on the decarboxylation and hydrolysis of arginine. Arginine was first converted to citrulline by the enzyme arginine dihydrolase . Citrulline was then converted to ornithine and ammonia, leading to an alkaline pH . A pH indicator (usually bromcresol purple) in the medium changed color from yellow to purple under alkaline conditions, indicating a positive result. 3. Materials Moeller’s decarboxylase base medium Arginine-containing medium (arginine dihydrolase broth) Sterile mineral oil Inoculating loop Incubator (35–37°C) Test organism (pure culture) Marker pen Control tubes (without arginine) 4. Procedure (Macroscopic) A loopful of pure culture was inoculated int...

                                          1. Objective The objective of the experiment was to detect and quantify disease-specific antigens or antibodies in hematological disorders using the ELISA technique. 2. Principle The ELISA technique was based on antigen-antibody interaction. Either the antigen or antibody was immobilized on a solid surface (usually a microtiter plate), and a corresponding enzyme-labeled antibody was used for detection. Upon addition of a chromogenic substrate, a color change occurred, which was measured spectrophotometrically and correlated with the concentration of the target molecule. 3. Materials Used Microtiter ELISA plate Patient serum or plasma samples Known standards and controls Enzyme-conjugated antibodies (e.g., anti-FVIII for Hemophilia A) Substrate (e.g., TMB – Tetramethylbenzidine) Stop solution (e.g., sulfuric acid) Plate washer and read...