PRINCIPLE AND EXPECTED VALUES 
Ascorbic acid: This test involves decolorization of Tillmann’s reagent. The presence of 
ascorbic acid causes the color of the test field to change from blue-green to orange. 
Glucose: This test is based on the enzymatic reaction that occurs between glucose 
oxidase, peroxidase and chromogen. Glucose if first oxidized to produce gluconic acid 
and hydrogen peroxide in the presence of glucose oxidase. The hydrogen peroxide 
reacts with potassium iodide chromogen in the presence of peroxidase. The extent to 
which the chromogen is oxidized determines the color which is produced, ranging from 
green to brown. Low amounts of glucose are normally excreted in urine.3 Glucose 
concentrations as low as 100 mg/dL, read at either 10 or 30 seconds, may be 
considered abnormal if results are consistent. At 10 seconds, results should be 
interpreted qualitatively. For semi-quantitative results, read at 30 seconds only. 
Bilirubin: This test is based on azo-coupling reaction of bilirubin with diazotized 
dichloroaniline in a strongly acidic medium. Varying bilirubin levels will produce a 
pinkish-tan color proportional to its concentration in urine. In normal urine, no bilirubin is 
detectable by even the most sensitive methods. Even trace amounts of bilirubin require 
further investigation. Atypical results (colors different from the negative or positive color 
blocks shown on the color chart) may indicate that bilirubin-derived bile pigments are 
present in the urine specimen, and are possibly masking the bilirubin reaction. 
Ketone: This test is based on ketones reacting with nitroprusside and acetoacetic acid 
to produce a color change ranging from light pink for negative results to a darker pink or 
purple color for positive results. Ketones are normally not present in urine. Detectable 
ketone levels may occur in urine during physiological stress conditions such as fasting, 
pregnancy and frequent strenuous exercise.4-6 In starvation diets, or in other abnormal 
carbohydrate metabolism situations, ketones appear in the urine in excessively high 
concentration before serum ketones are elevated.7 
Specific Gravity: This test is based on the apparent pKa change of certain pretreated 
polyelectrolytes in relation to ionic concentration. In the presence of an indicator, colors 
range from deep blue-green in urine of low ionic concentration to green and 
yellow-green in urine of increasing ionic concentration. Randomly collected urine may 
vary in specific gravity from 1.003-1.040. Twenty-four hour urine from healthy adults 
with normal diets and fluid intake will have a specific gravity of 1.016-1.022.8 In cases of 
severe renal damage, the specific gravity is fixed at 1.010, the value of the glomerular 
filtrate. 
Blood: This test is based on the peroxidase-like activity of hemoglobin which catalyzes 
the reaction of cumene-hydroperoxide and 3,3',5,5'-tetramethylbenzidine. The resulting 
color ranges from orange to green to dark blue. Any green spots or green color 
development on the reagent area within 60 seconds is significant and the urine 
specimen should be examined further. Blood is often, but not invariably, found in the 
urine of menstruating females. 
pH: This test is based on a double indicator system which gives a broad range of colors 
covering the entire urinary pH range. Colors range from orange to yellow and green to 
blue. The expected range for normal urine specimens from newborns is pH 5–7. The 
expected range for other normal urine specimens is pH 4.5–8, with an average result of 
pH 6. 
Protein: This reaction is based on the phenomenon known as the "protein error” of pH 
indicators where an indicator that is highly buffered will change color in the presence of 
proteins (anions) as the indicator releases hydrogen ions to the protein. At a constant 
pH, the development of any green color is due to the presence of protein. Colors range 
from yellow to yellow-green for negative results and green to green-blue for positive 
results. 1-14 mg/dL of protein may be excreted by a normal kidney.9 A color matching 
any block greater than trace indicates significant proteinuria. For urine with high specific 
gravity, the test area may most closely match the trace color block even though only 
normal concentrations of protein are present. Clinical judgment is required to evaluate 
the significance of trace results. 
Urobilinogen: This test is based on a modified Enhrlich reaction between 
p-diethylaminobenzaldehyde and urobobilinogen acid in strongly acidic medium to 
produce a pink color. Urobilinogen is one of the major compounds produced in heme 
synthesis and is a normal substance in urine. The expected range for normal urine with 
this test is 0.2-1.0 mg/dL (3.5-17 µmol/L). A result of 2.0 mg/dL (35 µmol/L) may be of 
clinical significance, and the patient specimen should be further evaluated. 
Nitrite: This test depends upon the conversion of nitrate to nitrite by the action of Gram 
negative bacteria in the urine. In an acidic medium, nitrite in the urine reacts with 
p-arsanilic acid to form a diazonium compound. The diazonium compound in turn 
couples with 1 N-(1-naphthyl)- ethylenediamine to produce a pink color. Nitrite is not 
detectable in normal urine.3 The nitrite area will be positive in some cases of infection, 
depending on how long the urine specimens were retained in the bladder prior tocollection. Retrieval of positive cases with the nitrite test ranges from as low as 40% in 
cases where little bladder incubation occurred, to as high as approximately 80% in 
cases where bladder incubation took place for at least 4 hours. 
Leukocytes: This test reveals the presence of granulocyte esterases. The esterases 
cleave a derivatized pyrazole amino acid ester to liberate derivatized hydroxy 
pyrazole. This pyrazole then reacts with a diazonium salt to produce a beige-pink to 
purple color. Normal urine specimens generally yield negative results. Trace results may 
be of questionable clinical significance. When trace results occur, it is recommended to 
retest using a fresh specimen from the same patient. Repeated trace and positive 
results are of clinical significance. 
bio-equip.cn  
  Span Biotech Ltd. is a research based company for rapid tests, with strong support from National Key Laboratory of Technology Projects of 10th and 11th Five-Year Plan and Faculty of Life Sciences of HuBei University. SpanBio also housed a R&D team that is developing gene recombination, cell cultivation and protein purification techniques. SpanBio pays strict attention on rapid tests for human being, animal diseases and food safety detection. It provides a number of customized services to professional distributors and partnering affiliates with excellent quality, competitive prices and super service. 
Efficiently structured to provide lasting and economic health care solutions with export ready goods, our main products cover the following immunodiagnostic rapid test kits: 
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2) Infectious diseases: Hepatitis B, HCV, HIV 
3) Drug abuse: AMP, BAR, BZO, COC, mAMP, MOP, MTD, OPI, PCP, TCA, THC 
4) Tumor markers: CEA, PSA, AFP, FOB 
5) STDs(Sexually Transmitted Diseases): Gonorrhea, syphilis, chlamydia 
6) New products: Malaria, H. Pylori, Multi-Hepatis B Panel (HBsAg, Anti-HBs, HBeAg, Anti-HBe, Anti-HBc), Blood Glucose Test, Multi-drug of Abuse Panel, Avian (Bird) Flu Rapid Test, etc. 
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1) Bovine: Cow Pregnancy , Cow Ovulation, Bovine Brucella, Bovine Tuberculosis ,Food and Mouth Disease NSP Ab Test 
2) Canine: Canine Distemper, Canine Parvovirus, Canine Coronavirus 
3) Feline : Feline Leukemia Virus Ag Rapid Test ,Feline Panleucopenia Virus Ag Test,Feline Immunodeficiency Virus Ab Test 
Rapid Tests for Food Safety : 
1)For Antibiotics Residue : Nitrofurans (AOZ,AMOZ, AHD, SEM), Streptomycin , Sulfonamides , Chloramphenicol , Quinolone , Beta-Lactam&Tetracycline Combo (2 in 1), β-Lactams & Streptomycin & Chloramphenicol & Tetracyclines Combo (4 in 1), Beta-Lactam, Tetracycline test 
2) For Beta-Agonist Residue : Ractopamine, Clenbuterol ,Salbutamol
   
 
 
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