The NH3 concentration was determined using the Nessler’s reagent colorimetry method28 (link). In detial, Nessler reagent was purchased from Sigma-Aldrich with product No. 72190. The NH3 and H2S gasses were collected by an integrated air collector (Tuowei Instrument Ltd, Qingdao, China). NH3 in the air was absorbed using 0.05 mol/L dilute H2SO4. The NH4 + ions react with the Nessler reagent to form a yellow–brown complex. The absorbance of the complex proportional to the NH3 concentration was determined at a wavelength of 420 nm. The H2S concentration was determined using the methylene blue spectrophometry method (GB/T11742-89, China). The absorbance was measured at a wavelength of 665 nm. The minimum detectable concentration was 0.001 mg/m3. The concentration of H2S was calculated according to formula that was published in a previous work29 (link).
Nessler reagent
Manufactured by Merck Group
Sourced in United States, Brazil
Nessler reagent is a chemical solution used in analytical chemistry for the detection and determination of ammonia. It is a sensitive reagent that reacts with ammonia to produce a characteristic yellow to brown color, the intensity of which is proportional to the amount of ammonia present in the sample. Nessler reagent is commonly used in water analysis, environmental monitoring, and various other applications that require the measurement of ammonia levels.
Automatically generated - may contain errors
Lab products found in correlation
Trichloroacetic acid, by Merck Group (2 mentions)
Asparagine, by Merck Group (2 mentions)
Trichloroacetic acid tca, by Merck Group (1 mentions)
Elx800, by Agilent Technologies (1 mentions)
L glutamine, by Merck Group (1 mentions)
Asparaginase, by Takeda Pharmaceuticals (1 mentions)
L asparagine, by Merck Group (1 mentions)
Glutamine, by Merck Group (1 mentions)
Aspartic acid, by Merck Group (1 mentions)
Dimethyl sulfoxide (dmso), by Thermo Fisher Scientific (1 mentions)
Poloxamer 407 pol 407, by Merck Group (1 mentions)
Fetal bovine serum (fbs), by Harvard Bioscience (1 mentions)
Bovine serum albumin (bsa), by Merck Group (1 mentions)
Dulbecco s modified eagle s medium dmem, by Merck Group (1 mentions)
Ammonium chloride, by Merck Group (1 mentions)
Copper 2 chloride dihydrate, by Merck Group (1 mentions)
Ethanol, by Merck Group (1 mentions)
Potassium hydroxide, by Merck Group (1 mentions)
Potassium chloride (kcl), by Merck Group (1 mentions)
2 propanol, by Merck Group (1 mentions)
9 protocols using nessler reagent
1
Determination of NH3 and H2S Concentrations
2
Glutaminase activity measurement protocol
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Glutaminase activity (GLS) was measured basing on the evaluation of NH3 released from L-glutamine [20 ]. Incubation mixture contained 0.04 M L-glutamine (Sigma-Aldrich) in 0.1 M phosphate buffer pH = 7.0 and serum samples and was incubated in 37°C for 30 minutes. The reaction was stopped by adding 1.5 M trichloroacetic acid (TCA) (Sigma-Aldrich). After centrifugation 5000 ×g for 3 minutes of samples Nessler reagent (Sigma-Aldrich) was added to the supernatant, and the mixture was further incubated in room temperature for 10 minutes. The absorbance was measured at 450 nm in microplate reader ELx800 (Bio-Tek). Blank samples contained water, TCA, L-glutamine, and Nessler reagent. The standard curve was prepared with the use of (NH4)2SO4 as a standard. One unit of glutaminase was defined as an amount of the enzyme which released one micromol of ammonia. Specific activity in PBMC was expressed in milliunits per milligram of protein and its serum activity in milliunits per liter.
3
Asparaginase Enzyme Activity Assay
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Mice were injected intravenously with 3 IU of asparaginase per g of body weight (Takeda). At the indicated times after injection, mice were euthanized by CO 2 /O 2 asphyxiation, a blood sample was drawn, and tissues of interest were dissected. When indicated, mice were pretreated with 150 mL (1 mg/mL clodronate) of liposomes or control liposomes (12) via tail vein injection 24 h before administration of 111 In-labeled asparginase. Residual asparaginase activity in serum was determined by photometric detection of the ammonia release after reaction with Nessler reagent (Sigma-Aldrich). In brief, 15 mL of serum were diluted with 60 mL of 44 mM L-asparagine (Sigma-Aldrich) dissolved in 15 mM Tris-HCl buffer, pH 7.3, supplemented with 0.015% (w/v) bovine serum albumin and incubated at 37°C for 30-45 min. The reaction was stopped by the addition of 50 mL of trichloroacetic acid (24.5% [w/v]; Sigma-Aldrich). After centrifugation, 15 mL of the supernatant was added to 120 mL of Nessler solution diluted with deionized water (1:8). The optical density of the solution was measured at 450 nm using the Multiskan Ascent plate reader (MTX Lab Systems).
4
Asparaginase Enzymatic Assay Protocol
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Asparaginase was obtained from Changzhou Qianhong Bio-Pharma Co., Ltd. (Jiangsu, China). Asparagine, aspartic acid, and Poloxamer 407 (Pol 407 ) were obtained from Sigma (USA). BSA, Dulbecco's modified Eagle's medium (DMEM), glutamine, tetrazolium bromide (MTT), and Nessler reagent were obtained from Sigma-Aldrich (USA). Dimethyl sulfoxide (DMSO) was obtained from Fisher Scientific (USA) and fetal bovine serum (FBS) from Biochrom (Berlin, Germany).
5
Ammonium Content Determination in Seedlings
6
Micro-Kjeldahl Nitrogen Determination
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Determination of total reduced nitrogen followed a simplified version of the micro-Kjeldahl procedure reported by [43] . Leaf material (30 mg dry matter) was homogenized in 1 ml 0.01 M KOH and 200 µl of this homogenate was transferred to micro-Kjeldahl tubes, mixed with 100 µl combustion acid (4.2 M H2SO4 containing 5.4 g/l HgCl2) and incubated in a sand bath first at 160°C for 40 min and then for 2 h at 300°C. The samples were allowed to cool to room temperature, then 50 µl H2O2 (30%) were added, followed by further incubation at 160°C during 1 h and at 300°C for 2 h. After a second addition of 50 µl H2O2 (30%) and further incubation at 160°C for 15 min, 1 ml water was added followed by colorimetric determination of the reduced nitrogen (ammonium) by mixing 50 µl of this sample solution with 100 µl 2.5% K-Na-tartrate (w/v) and 100 µl dilute Nessler Reagent (1 part of Nessler Reagent Merck Nr 109028 and two parts 2.5 M NaOH). Absorbance was measured at 450 nm.
7
Electrochemical Characterization of Metal Foils
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Titanium Foil (Ti), Copper
Foil (Cu), Graphite Foil (Gr), and sodium carbonate (NaCO3) were supplied from Thermo Scientific Chemicals (Alfa-Aersar). Copper(II)
chloride dihydrate (CuCl2·2H2O), potassium
chloride, potassium hydroxide, ethanol, 2-propanol, and propanone
were purchased from Sigma-Aldrich. Merck supplied potassium nitrate
(KNO3), Nessler reagent, ammonium chloride (NH4Cl), and sodium hydrogen carbonate (NaHCO3).
Foil (Cu), Graphite Foil (Gr), and sodium carbonate (NaCO3) were supplied from Thermo Scientific Chemicals (Alfa-Aersar). Copper(II)
chloride dihydrate (CuCl2·2H2O), potassium
chloride, potassium hydroxide, ethanol, 2-propanol, and propanone
were purchased from Sigma-Aldrich. Merck supplied potassium nitrate
(KNO3), Nessler reagent, ammonium chloride (NH4Cl), and sodium hydrogen carbonate (NaHCO3).
8
Ammonia Production Assay for Bacteria
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Bacterial isolates were checked for ammonia production using the method of Cappuccino and Sherman [16 ]. The 12 h old bacterial cultures were inoculated in 10 mL of peptone broth and incubated for 48 h at 28 ± 0.1 °C. The appearance of a faint yellow to dark brown color upon the addition of a 0.5 mL Nessler reagent (Merck) to the cultures indicated the production of ammonia.
9
Encapsulation of L-Asparaginase in PLGA
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
L-Asparaginase was obtained from Changzhou Qianhong Bio-Pharma Co. Ltd. (Changzhou, Jiangsu, China). 50:50 (w/w) poly (lactic-co-glycolic acid) (PLGA) with average molecular weight (Mw) of 24--38 kDa and 30--60 kDa, designated as PLGA 1 and PLGA 2, respectively, polyvinyl alcohol (PVA) (Mw of 31-50 kDa), bicinchoninic acid (BCA) assay kit, asparagine and trichloroacetic acid were purchased from Sigma Aldrich® (São Paulo, SP, Brazil), while the Nessler reagent was obtained from Merck Millipore® (Barueri, SP, Brazil). All the other analytical grade reagents were purchased from Synth® (São Paulo, SP, Brazil), while water was purified using a Milli-Q water purification system (MilliPore, Bedford, MA, USA).
About PubCompare
Our mission is to provide scientists with the largest repository of trustworthy protocols and intelligent analytical tools, thereby offering them extensive information to design robust protocols aimed at minimizing the risk of failures.
We believe that the most crucial aspect is to grant scientists access to a wide range of reliable sources and new useful tools that surpass human capabilities.
However, we trust in allowing scientists to determine how to construct their own protocols based on this information, as they are the experts in their field.
Ready to get started?
Sign up for free.
Registration takes 20 seconds.
Available from any computer
No download required
Revolutionizing how scientists
search and build protocols!