Ammonia in urine

When ammonia is found in biological materials at physiological pH (7.2), most of it (99%) will be found as ammonium ion, due to its pK of 9.2. This is an important consideration for any subsequent analysis. The determination of ammonia (as dissolved NH3 and ammonium ion) in blood, plasma, or semm is of value in detecting existing or impending hepatic coma and Reyes Syndrome (Meyerhoff and Robins 1980 Tietz 1970). The determination of ammonia in urine had historically been used as an indicator of the kidney s ability to produce ammonia however, this procedure has been replaced by more modem and accurate tests for kidney function. Procedures for the determination of ammonia in biological samples are found in Table 7-1. Ammonia is also tested for in calculi (abnormal concretions in the body formed of mineral deposits, often found in the gall bladder, kidney, or bladder) (Tietz 1970) however, this is not a quantitative test and is not included in Table 7-1. 

The ancients, who didn t have nitric acid, derived their nitrogen from ammonia in urine and/or from distillation of dung and bones to get sal ammoniac. Ammonium compounds behave as weak acids and alchemists usually enhanced them with saltpeter (potassium nitrate, KNO3). 

Methods based on converting an analyte into a gaseous phase to be separated through membranes are used, e.g., ammonia in urine is released by... 

Observation of the ion-exchange properties of soils 1858 Zeolites natural ion-exchangers in the soils 1917 Determination of ammonia in urine using a synthetic zeolite... 

Glassy carbon spheres with anthraquinone moieties - 9 X 10 M 5 X 10 -3 X 10 M Determination of ammonia in urine and soil samples also explored 15... 

For humans, 80-90% of ingested nitrogen is excreted as urea. Minor contributions include ammonia and creatinine (in urine), nitrogen compounds in... 

Nitrogen compounds commonly determined are creatinine, urea, and uric acid. Creatinine is an end product of the energy process occurring within the muscles, and is thus related to muscle mass. Creatinine in urine is commonly used as an indicator and correction factor of dilution in urine. Creatinine in serum is an indicator of the filtration capacity of the kidney. Urea is the end product of the nitrogen luea cycle, starting with carbon dioxide and ammonia, and is the bulk compoimd of urine. The production of uric acid is associated with the disease gout. In some cases, it appears that the excess of uric acid is a consequence of impaired renal excretion of this substance. 

One of the major constituents of urine is the di-amine, urea (III). Each amine group in urea should remind us of ammonia in Equation (6.11). Solutions of urea in water are basic because the two amine moieties each abstract a proton from water, to generate an ammonium salt and a hydroxide ion ... 

VALLIS, I., HARPER, L.A., CATCHPOOLE, V.R., and WEIER, K.L. (1982). Volatilisation of ammonia from urine patches in a sub-tropical pasture. Australian Journal Agricultural Research 33, 97-107. 

During conditions of acidosis, hydrogen ions are excreted (secreted) by the kidney to maintain the normal pH of the blood. These ions are buffered in urine by ammonia, in the reaction... 

This potassium sparing diuretic causes a moderate increase in excretion of sodium and bicarbonate ions in urine, and it raises excretion of potassium and ammonia ions. It has little effect on urine volume. 

Uses Suppress/eluninate bacteriuria associated w/ chronic/recurrent UTI Action Converted to formaldehyde ammonia in acidic urine nonspecific bactericidal action Dose Adults. Hippurate 0.5-1 g bid. Mandelate 1 g qid PO pc hs Peds 6-12 y. Hippurate 25-50 mg/kg/d PO bid. Mandelate 50-75 mg/kg/d PO qid (take w/ food, ascorbic acid w/ adequate hydration) Caution [C, +] Contra Renal insuff, severe hepatic Dz, severe dehydration sulfonamide allergy Disp Tabs SE Rash, GI upset, dysuria, t LFTs EMS Monitor BP for hypovolemia and dehydration OD Sxs unknown symptomatic and supportive... 

Gastric distress (nausea and vomiting) is one of the most frequently reported adverse reactions. Bladder irritation (e.g., dysuria, polyuria, hematuria, and urgency) may occur. The mandelic salt can crystallize in urine if there is inadequate urine flow and should not be given to patients with renal failure. Patients with preexisting hepatic insufficiency may develop acute hepatic failure due to the small quantities of ammonia formed during methenamine hydrolysis. 

UREASE. Enzyme present in low-percentages in jackbean and soybean water soluble, its action is inhibited by heavy-metal ions. Its principal use is in the determination of urea in urine, blood, and other body fluids it splits urea into ammonia and carbon dioxide or ammonium carbonate. 

Urea [57-13-6] was discovered in urine by Rouelle in 1773 and first synthesized from ammonia (qv) and cyanic acid by Woehler in 1828. This was the first synthesis of an organic compound from an inorganic compound, and it dealt a deathblow to the vital-force theory. In 1870, urea was produced by heating ammonium carbamate in a sealed tube. 

LiChrosorb Si 60 or Polygosil Cis Methanol-aqueous ammonia-dichloromethane for omeprazole and its sulfone in plasma or acetonitrile-phosphate buffer for the hydroxy metabolite in plasma and all compounds in urine 302 Analysis of omeprazole and metabolites in plasma and urine. Drug and metabolites are extracted in CH2CI2 [91]... 

Urea, which is also known as carbamide and carbonyldiamide, was discovered in urine by Rouelle in 1773. It was first synthesized from ammonia and cyanic acid by Woehler in 1828 . In the early 1900 s urea was produced on an industrial scale by the hydration of cyanamide, which was obtained from calcium cyanamide109 ... 

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