Product Name: TD19C6

Description:

Appearance: white powder
Purity: pass test (TLC)

TD19C6 is an ammonium ion selective ionophore. It is difficult to separate ammonium ion and potassium ion because they are close in ion size. The selectivity of TD19C6 for ammonium ion is about 10 times that of potassium ion, which is nearly the same selectivity of nonactin.

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Product Name: ALC

Description:

Appearance: orange yellow or yellowish brown powder
Absorbance (1.0x10-4 M in acetate buffer): >0.42 (430 nm)
Sulfated ash: <0.5 %
Solubility: 100 mg/10 ml 0.1 M NaOHa50 ml water

ALC is utilized for colorimetric detection of fluoride ion. A red solution of the La(III) or Ce(III) complex turns blue in the presence of fluoride ions. The maximum wavelength of the fluoride complex is 620 nm at pH 4-5. As little as 0.1 to 1 ppm of fluoride ion can be determined using this method. The structure of this complex has been reported as La₂L₂F₂, (La₅L₄F₂)_n or Ce₅L₄F₄ (L: ALC). ALC is insoluble in alcohol and ether, slightly soluble in water, and easily soluble in alkaline water. The fluoride complex can be extracted with isoamylalcohol. Since ALC is less toxic than Alizarin red, it is used to mark and trace young fish. The aqueous solution of ALC is yellow at pH < 6, red at pH 6 - 10, and blue violet at pH > 11. ALC can also be used to detect aluminum ions. pKa₁(COOH)=2.40, pKa₂(OH)=5.54, pKa₃(NH⁺)=10.07, pKa₄(OH)=11.98 (m=0.1).

 

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Product Name: Alfusone

 

Description:

Appearance: purple powder
pH: 5.0-5.3/ Sensitivity: pass test
Solubility: 50 mg/ml water

Alfusone is a complex of ALC, lanthanium and buffer that is utilized for colorimetric detection of fluoride ion. Working solution for fluoride detection can be prepared using 5% Alfusone solution. The maximum wavelength of the fluoride complex is at 620 nm. Dr. Wada and others used Alfusone for fluoride detection by flow-injection analysis. They were able to detect 0.03-1.2 ppm of fluoride in 24 samples within one hour.

Working Solution
1. Prepare 5% Alfusone using deionized or double-distilled water.
2. Mix 5 ml of 5% Alfusone solution, 25 ml acetone and 20 ml water.
3. Incubate the mixture at room temperature for 60-90 min and then use for assays.

 

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Product Name: Co(III)-5-Cl-PADAP

Description:

Appearance: dark purple crystals
Molar absorptivity: >84,000 (585 nm)
Solubility: 70.2 mg/10 ml methanola100 ml water

Since Co(III)-5-Cl-PADAP is not influenced by chloride or nitrate ions, it is suitable for the colorimetric determination of anionic detergents in seawater. Anionic surfactant can be determined at the ppb level.

Protocol
1. Add 1 ml HCl (5 M), 1 ml Co(III)-5-Cl-PADAP (0.1% w/v), and 5 ml toluene to 50 ml of sample solution.
2. Shake the mixture for 5 minutes.
3. Discard the aqueous phase, and wash the toluene solution with 25 ml Co(III)-5-Cl-PADAP (0.002% w/v, pH 1 HCl).
4. Measure the absorbance of the toluene phase at 560 nm.

 

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Product Name: Colloid Titration Reagent D

 

Description:

Reagent D: 5 bottles
   2 % aqueous Toluidine Blue solution

Colloid titration is a volumetric method for determining charged polyelectrolytes in aqueous solution. Since charged polyelectrolytes are frequently found in aqueous systems, this analytical procedure has wide applications for the water quality check in various industries, such as agar, leather, food, paper and pulp, and surfactant produtions. Reagent C, Zephiramine, is used as a standard for colloid titration. Reagent D, Toluidine Blue, has a positive charge and changes its color from blue to reddish-purple in the presence of negatively charged polyelectrolytes. Therefore, the endpoint of colloid titration can be determined by the color change.

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Metal Ion

 

Product Name: 3,5-DiBr-PAESA

3,5-DiBr-PAESA is an excellent colorimetric reagent for Cu(II) and Ag(I) detection. The maximum wavelength and molar absorptivity of the Ag(I) complex are 618 nm and 80,000, respectively. The maximum wavelength and molar absorptivity of Cu(I) are 639 nm and 1.34x10⁵, respectively. The absorption maximum of the complex shifts to longer wavelengths and the molar absorptivity increases in the presence of anionic surfactants such as sodium dodecylsulfate.

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Product Name: 5-Br-PADAB

5-Br-PADAB is a selective colorimetric reagent for Co, Cu, Fe, Ni and Pd. This reagent is highly sensitive for Co, and forms dark orange complexes, CoL2, which are barely soluble in water. This chelate generates three different complexes by protonation under acidic conditions. One of the complexes, CoL2H22+ has a blue violet color (lmax=572 nm, e=117,000), and can be extracted with water at acidic pH. Though 5-Br-PADAP also forms colored complexes with Fe, Cu, Ni and Zn, these complexes are decomposed under strong acidic conditions.

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Product Name: 5-Br-PAPS

5-Br-PAPS, a water-soluble derivative of 5-Br-PADAP, is a highly sensitive colorimetric reagent for zinc detection. This reagent forms a red chelate with zinc at pH 7.5-9.5 (lmax=552 nm, e=130,000). 5-Br-PAPS is also utilized for the determination of Cu(II), Fe(II), Ni(II), Co(II), Pt(II), Ru(II) and Rh(II). 5-Br-PAPS is utilized to determine serum levels of Zn, Cu, Fe, Ni and Co. For serum Zn levels, Fe ions can be masked with citric acid or metaphosphoric acid, and fluoride and Cu ions can be masked with 2-mercaptobenzothiazole or dithiocarboxysarcosine. 5-Br-PAPS-Ti complex can be used for hydrogen peroxide detection.

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Product Name: 5-Br-PSAA

5-Br-PSAA is a water-soluble colorimetric reagent for Fe(II) and Co(III) detection. This reagent forms colored complexes with Fe, Ni, Cu and Co, but not with Zn. The Fe(II) and Co(III) complexes are very stable, and even EDTA cannot remove metals from these complexes. However, Cu(II) and Ni(II) complexes are decomposed by EDTA, so 5-Br-PSAA can be used to determine Fe(II) in the presence of Cu(II) or Ni(II). The molar absorptivity of Fe(II) is reported to be 8.9x10⁴ (lmax=558 nm). The 5-Br-PSAA assay is 4 times as sensitive as Bathophenanthroline assay. Dr. Sakai and others determined ppb levels of Pb (e=98,400) using 5-Br-PSAA by flow injection analysis. Dr. Makino and others determined Cu(II) in 0.2 ml of serum by direct colorimetric detection (lmax=580 nm, e=64,000).

 

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Product Name: Arsemate

Arsemate is soluble in pyridine and chloroform, but insoluble in water and other organic solvents. For arsenic detection, a 0.5% Arsemate/pyridine solution is used. The sample should be treated with sulfuric acid, 15% potassium iodide and 40% SnCl₂/HCl solution to convert arsenic to AsH₃. Arsemate reacts with AsH₃ in pyridine and forms red colloidal silver with maximum wavelength at 520-540 nm. The detection range of arsenic using the Arsemate/pyridine solution is 4-12 ppm. Alternatively, 0.5% Arsemate/chloroform solution with 30 mM triethylamine can be used for the assay. For the colorimetric detection of arsenic, the AsH₃ gas generator is required.

 

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Product Name: Azomethine H

Azomethine H is a colorimetric reagent for boron detection; it forms an orange complex with boron in aqueous solution. The molar absorptivity of this complex is 1.01x10⁴ at 415 nm. The detection range of boron in sample solutions is 1-6 µg/ml. To detect boron in plant samples, EDTA is used to mask cupper, iron, and aluminum ions. Azomethine H is used to detect microgram levels of boron in glass and steel samples.

Working Solution
1. Mix 9 g Azomethine H and 2 g ascorbic acid with 700 ml deionized or double-distilled water.
2. Heat the mixture at 70 ºC or lower to dissolve Azomethine H.
3. Add water to prepare 1000 ml assay solution.

 

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Product Name: Bathocuproine

Bathocuproine is a Cu(I)-specific colorimetric reagent. An orange Bathocuproine-Cu(I) complex can be extracted with n-hexylalcohol or iso-amylalcohol. The maximum wavelength of the complex extract is 479 nm. The Cu(I) detection range is 0.1-10 ppm. Bathocuproine has been used to determine trace amounts of Cu(I) in wine and purified tellurium samples. Bathocuproine is soluble in organic solvents such as nitrobenzene and insoluble in water.

 

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Product Name: Bathocuproinedisulfonic acid, disodium salt

 

Bathocuproinedisulfonic acid is a water-soluble analog of bathocuproine that emits fluorescence under UV light. Since the Bathocuproine-Cu(I) complex formed by this analog is water-soluble, Cu(I) can be determined by direct measurement of the assay solution at 483-522 nm without solvent extraction. The molar absorptivity of the bathocuproinedisulfonic acid-Cu(I) complex is 1.2x10⁴.
Dr. Faizullah developed a system to quickly determine Cu(I) at around 30 ppm by using Bathocuproine-disulfonic acid in flow injection analysis. Dr. Sawada developed a highly sensitive Cu(I) detection system using the long flow cell. Dr. Sawada? system can detect as little as 0-15 ppb Cu(I) in water samples without pretreatment.

 

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Product Name: Bathophenanthroline

 

Bathophenanthroline is a highly selective colorimetric reagent for Fe(II) detection. Bathophenanthroline is soluble in organic solvents and slightly soluble in acidic aqueous solutions, but insoluble in neutral or alkaline solutions. It chelates with Fe(II) at pH 2-9, and the red color complex can be extracted with isoamylalcohol (logb₃=21.8, lmax=533 nm, e=22,400). The detection range of Fe(II) by Bathophenanthroline is 10 ppb to 4 ppm. The pKa₂ of Bathophenanthroline is reported to be 4.30 in a 50% dioxane solution (µ=0.3) at 25 ºC, and the reduction and oxidation potential of FeL₃²⁺-FeL₃³⁺ in the 1 M H₂SO₄ solution is 1.24 V. Cu(I) and Ru(II) can also be detected using Bathophenanthroline. The maximum wavelength of the Cu(I) and Ru(II) complexes are 457 nm and 460 nm, respectively.

 

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Product Name: Bathophenanthrolinedisulfonic acid, disodium salt

Bathophenanthrolinedisulfonic acid, disodium salt is a water-soluble derivative of Bathophenanthroline. It is insoluble in organic solvents. Its pKa₁ and pKa₂ are 2.83 and 5.20, respectively. Due to its high water solubility, Bathophenanthrolinedisulfonic acid, disodium salt can be used to detect Fe(II) in aqueous samples such as blood or biological fluids. The detection range of Fe²⁺ using Bathophenanthrolinedisulfonic acid is 0.25-4 ppm at 535 nm. The molar absorptivity of the complex is 2.24x10⁴. The reduction and oxidation potential of FeL₃²⁺-FeL₃³⁺ in 1 M H<sub>2SO₄ solution is reported to be 1.09 V. Cu⁺ can also be detected using Bathophenanthroline-disulfonic acid, disodium salt. The maximum wavelength and molar absorptivity of the Cu⁺ complex is 483 nm and 1.23x10⁴, respectively.

 

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Product Name: Bis (12-crown-4)

The NAS11-8 glass electrode is utilized as a selective sodium ion sensor. However, it is easily spoiled by biomaterials in sample solutions. Bis(12-crown-4), a sodium ionophore, is 100 times more selective for sodium than potassium in the PVC electrode using NPOE as a plasticizer. The same selectivity for sodium over potassium is reported when Bis(12-crown-4) is used on a coated wire electrode. It can be used in either a liquid membrane or a PVC membrane. TFPB, a lipophilic anion, can help improve detection sensitivity.
Ion selectivity: LogK^pot(Na/Li):-3.0, LogK^pot(Na/K):-2.0, LogK^pot(Na/Cs):-2.0, LogK^pot(Na/Rb):-2.4, LogK^pot(Na/NH4):-3.0, LogK^pot(Na/Mg):-4.0, LogK^pot(Na/Ca):-4.0, LogK^pot(Na/Ba):-3.7, LogK^pot(Na/Sr):-3.7
Formulation: Ionophore: 6%, NPOE: 70%, TFPB: 50 mol% of ionophore

 

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Product Name: Bis (benzo-15-crown-5)

Bis(benzo-15-crown-5) is a potassium selective ionophore. Its potassium ion selectivity is almost equal to that of valinomycin, which is a well-known neutral carrier for the potassium ion in nature. This reagent, combined with NPOE as a plasticizer, is the most recommended ionophore for potassium-selective PVC membrane electrodes. This ionophore also forms a thallium complex, so it can be used for thallium sensors.
Ion selectivity: LogK^pot(K/Na):-3.6, LogK^pot(K/Rb):-0.7, LogK^pot(K/NH4):-2.0, LogK^pot(K/Cs):-2.0
Formulation: Ionophore: 2.7%, NPOE: 70%, TFPB: 50 mol% of ionophore/PVC, THF

 

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Product Name: Bismuthiol-II

Bismuthiol-II is utilized for colorimetric determination of various metal ions with solvent extraction. Though Bismuthiol-II solution is colorless, it forms stable metal complexes with various colors. Bismuthiol-II forms complexes with As, Fe, Se and Te that can be extracted with chloroform in strong acidic condtions. Since Te detection with Bismuthiol-II is 20 times more sensitive than with diethyldithiocarbamate, it is used for Te determination in alloys, copper and pearlite.

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Product Name: Bisthiourea-1

Bisthiourea-1 is a chloride-selective neutral ionophore, and it is utilized for preparation of chloride electrodes. Bisthiourea-1 forms a 1:1 complex with chloride ion. The detection limit of chloride ion using Bisthiourea-1 is 6.5±3.0 x 10^-6 M.

 

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Product Name: BT

BT in aqueous solution changes color according to pH: red at pH<6, blue at pH 7-11, and orange at pH>12. Its proton dissociation constants are reported to be pKa₂=6.3 and pKa₃=11.55 (m=0.08, 20 ºC). BT is one of the most commonly used indicators of Ca, Mg, Zn, Cd, Pb, Hg and rare earth metals for EDTA chelate titration. BT solution turns red in the presence of the metals at pH 10, and then changes to blue at the endpoint of the titration. Cu and Fe(III), as well as Al, Co and Mn(III), should be masked with KCN because they interfere with the color change. Triethanolamine is also a suitable masking reagent for Al, Fe(III), and Mn(III). Since metal ions such as Mn(III) and Fe(III) oxidize BT, hydroxylamine and hydrochloride should be added to prevent oxidation.

 

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Product Name: C14-K22B5

C14-K22B5 is the best magnesium selective ionophore available. The PVC membrane stability is improved by this ionophore? high lipophilicity due to tetraoctadecane and adamantyl groups. C14-K22B5 has a linear response between 1x10^-5 M and 0.1 M magnesium ion.

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Product Name: Calcein

Calcein is a fluorescent metal indicator for calcium detection with EDTA titration. It is slightly soluble in water. The proton dissociation constants are reported to be pKa₁=2.1, pKa₂=2.9, pKa₃=4.2, pKa₄=5.5, pKa₅=10.8 and pKa₆=11.7. Calcein solution emits a yellowish-green fluorescence in acidic conditions, and no fluorescence in basic conditions. However, Calcein will emit fluorescence in the presence of metal ions such as Al, Ba, Ca, Cu, Mg and Zn in basic conditions. Therefore, Calcein is also used for direct fluorometric EDTA titration of these metal ions. Since Calcein has a clear endpoint even if the sample has color or contains phosphate, it is suitable for calcium detection in biological samples or fertilizers. TPC, murexide or PPC are added to get a clear endpoint. For example, by mixing equal amounts of TPC with Calcein, intense green fluorescence will turn reddish-purple with no fluorescence at the endpoint.

 

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Product Name: Calcein Blue

Calcein Blue is a fluorescent metal indicator in EDTA titration. It is easily soluble in alkaline solutions, but barely soluble in water. Its proton dissociation constants are reported to be pKa₁=2.45, pKa₂=7.24 and pKa₃=11.3. Calcein Blue solution emits bright blue fluorescence (lem=445 nm) at pH 4-11, but no fluorescence at pH 12 or higher. The blue fluorescence of the Calcein Blue solution at pH 4-11 is quenched by metal ions such as Co, Cu, Mn, Ni and Pb. However, Calcein Blue forms a highly fluorescent complex with alkaline earth metals at pH 12 or higher. Since the endpoint of the chelate titration is clear by UV irradiation at 200-370 nm in a dark room, highly stained sample can be used. Calcein Blue is also suitable to determine Fe and Zr ions. Calcein Blue-Zn chelate can detect 10 ppb of F^-. Calcein Blue aqueous solution emits laser at 449-490 nm.

 

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Product Name: Chlorophosphonazo-III

Chlorophosphonazo-III is a colorimetric reagent for thorium, uranium, lanthanoids, actinoids and alkaline earth metals. This reagent is readily soluble in water and is violet at pH 4 or lower, blue in NaOH solution, and brilliant green in acids such as H₂SO₄, HCl and diluted HNO₃ (it decomposes in concentrated HNO3). Its proton dissociation constants are reported to be -1.1, -1.1, 0.6, 0.8, 1.5, 2.5, 5.47, 7.20, 12.15 and 15.13 (µ=0.1, 20 ºC). Chlorophosphonazo-III is used as a selective colorimetric reagent for calcium in a mixed Ca/Mg sample in the pH range of 2-3. It is also a useful indicator for the precipitation titration of SO₄^2- using Ba²⁺ as a standard solution.

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Product Name: Chromotropic acid

Chromotropic acid is utilized for the determination and detection of various metal ions and organic compounds such as B, Fe, Th, Ti, U, Zr and carbonyl compounds. Chromotropic acid forms an orange complex with Ti that can be determined by the absorbance at 460-470 nm. Chromotropic acid also reacts with formaldehyde to generate a reddish-purple compound by a condensation reaction with sulfuric acid. Therefore, it can be used for the determination of aldehyde compounds such as glyceroaldehyde, flufural and alcohols treated with manganese peroxide. For example, methanol, arabinose and glucose can be determined using manganese peroxide. Ammonium ion is also determined with Chromotropic acid.

 

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Product Name: Cu-PAN

Cu-PAN, a mixture of Cu-EDTA and pyridylazo-naphthol, is a very popular metal indicator for chelatometry. Usually, 20-50% aqueous dioxane (or isopropylalcohol) or 50-70% aqueous methanol (or ethanol) is used as a solvent (1 g Cu-PAN per 100 ml solvent). The solution should be heated during the chelating titration. However, a clear endpoint can be seen without heating by adding an equal volume of organic solvents such as isopropylalcohol or dioxane.

Applications
Chelate titration (acidic condition): Al, C, Co, Fe(III), Ga, Hg, In, Ni, V, Zn, rare earth metal ions
Chelate titration (alkaline condition): Ca, Cu, Mg, Mn(II)

 

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Product Name: Cyanoline Blue

 

Cyanoline Blue is a mixture of monopyrazolone and bispyrazolone. It is used as a colorimetric reagent for CN^- detection. The detection range of CN^- by this method is 5 ppb to 10 ppm. The maximum wavelength is 620 nm. A ready-to-use solution can be prepared by dissolving 0.27g Cyanoline Blue in 20 ml pyridine, followed by dilution with 100 ml water. The solution is stable for one week at 4 ºC. Cyanoline Blue is also used to detect SCN^-, OCN^-, NH₃ and vitamin B₁₂.

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Product Name: DAN

DAN is a highly selective colorimetric and fluorometric reagent for Se detection. This reagent is almost insoluble in cold water and alcohol, but it is easily soluble in water at 50 ºC. DAN forms 4,5-benzopiaselenol by the complex with Se, and this complex is extracted with chloroform, toluene or cyclohexane. Since the Se complex is volatile, Se can be determined by gas chromatography. HPLC can detect Se in tap and rain water at the picogram level. Further, DAN generates fluorescent naphthalenetriazole by the reaction with nitrite ion, so it is also used for the fluorometric determination of nitrite.

Applications
Solvent extraction, colorimetric: Se(IV) (in toluene at pH 1.2-2.2, lmax=380 nm, e=11,800, detection range 0-4 ppm)
Solvent extraction, fluorometric: Se(IV) (lem=520 nm in toluene, lem=538 nm in cyclohexane, detection range 1-100 ppb)

 

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Product Name: Diantipyrylmethane

Diantipyrylmethane is a colorimetric reagent for Ti detection, and is also used as a gravimetric and solvent extraction reagent for various kinds of metal ions. This reagent is readily soluble in mineral acids and organic solvents, and slightly soluble in benzene (1.7%) and carbon tetrachloride (0.28%). Diantipyrylmethane forms a yellow complex with Ti in 0.5-4 M HCl solution (lmax=385-390 nm, e=15,000). The resulting Ti complex can be extracted by organic solvents in the presence of I^-, SCN^-, tartaric acid or pyrocatechol. The detection range is 0.2-3 ppm. Diantipyrylmethane also makes a brown water-soluble complex with Fe in a weak acidic solution.

Application
Solvent extraction, colorimetric detection: Fe (lmax=450 nm, e=5,400), Mo, Ti, U
Gravimetric detection: Be, Ca, Cd, Co, Cu, Hg, Ir, Os, Pb, Sr, Tl, Zn

 

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Product Name: Dibenzyl-14-crown-4

Dibenzyl-14-crown-4 is 200 times more selective for lithium than for sodium or potassium. Though Dibutyl-phenanthroline is 1000 times more selective for lithium than sodium at a controlled pH, Dibenzyl-14-crown-4 is less pH-sensitive.
Selectivity: LogK^pot(Li/Na): -2.5, LogK^pot(Li/K): -2.3, LogK^pot(Li/Cs): -1.6, LogK^pot(Li/Rb): -2.2, LogK^pot(Li/NH4): -3.1, LogK^pot(Li/H): -3.2, LogK^pot(Li/Mg): -4.3, LogK^pot(Li/Ca): -4.9, LogK^pot(Li/Ba): -4.7, LogK^pot(Li/Sr): -4.3
Formulation: Ionophore: 1%, NPOE: 70%, K-TCPB: 50 mol% of ionophore/PVC, THF

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Product Name: HDOPP-Ca

HDOPP-Ca is a liquid cation exchanger for use in the calcium ion selective electrode. HDOPP is the most suitable compound among the dialkyl phosphate derivatives, and is used in either a liquid membrane or a PVC membrane using DOPP (dioctylphenylphosphate calcium salt) as a plasticizer.

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Product Name: HNB

HNB is a metal indicator for calcium, and a colorimetric reagent for alkaline earth metal ions, rare earth metal ions and uranium ions. HNB is readily soluble in water and alcohol. Aqueous solution of HNB is blue at pH 7-12, red above pH 13 and pink in the presence of calcium at pH 10. The detection range of alkaline earth metal ions and rare earth metal ions are 1-600 ppm and 1-300 ppm, respectively. The maximum wavelength of the complex is 650 nm. HNB is also used for UO2(II) detection. The proton dissociation constants of HNB are reported to be pKa₄=6.44 and pKa₅=12.91(µ=0.1, 24 ºC).

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Product Name: Ionophore-K23E1

ETH1001 is widely used for calcium selective electrodes. Ionophore-K23E1, a diazacrown compound with coordinate groups on the side arm, is more selective for calcium than ETH1001.
LogK^pot (Ca/Li): -4.1, LogK^pot (Ca/Na): -4.1, LogK^pot (Ca/K): -4.3, LogK^pot (Ca/Mg): -4.8

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Product Name: Murexide

MX is a 1:250 mixture of Murexide and potassium sulfate. Murexide is a metal indicator for Ca, Co, Cu, Ni, Th and rare earth metals; it is also a colorimetric reagent for calcium and rare earth metals. Murexide is slightly soluble in water, alcohol and ether. Murexide is unstable in aqueous solution. Its proton dissociation constants are reported to be pKa₁=0, pKa₂=9.2 and pKa₃=10.5. The solution is yellow in strong acidic conditions, reddish-purple in weak acidic conditions, and blue-purple in alkaline conditions. Detection conditions for calcium are pH 11.3, maximum wavelength 506 nm and detection range 0.2-1.2 ppm.

 

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Product Name: MX

MX is a 1:250 mixture of Murexide and potassium sulfate. Murexide is a metal indicator for Ca, Co, Cu, Ni, Th and rare earth metals; it is also a colorimetric reagent for calcium and rare earth metals. Murexide is slightly soluble in water, alcohol and ether. Murexide is unstable in aqueous solution. Its proton dissociation constants are reported to be pKa₁=0, pKa₂=9.2 and pKa₃=10.5. The solution is yellow in strong acidic conditions, reddish-purple in weak acidic conditions, and blue-purple in alkaline conditions. Detection conditions for calcium are pH 11.3, maximum wavelength 506 nm and detection range 0.2-1.2 ppm.

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Product Name: Nitro-PAPS

Nitro-PAPS is a highly sensitive colorimetric reagent for Fe(II) detection that forms a water-soluble complex at pH 3.0-8.0 (lmax=582 nm, e=107,000). This reagent is suitable for the determination of Fe(II) in serum, and can also be used to determine micromolar levels of Cu, Zn, Ni and Co. Cu and Zn in serum are masked by a mixture of thioglycolic acid and SDS. Zn in serum can be determined by Nitro-PAPS using CN- as a masking reagent of Fe and Cu.

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Product Name: Nitrophenylazo-15-crown-5

 

Nitrophenylazo-15-crown-5 is a chromogenic crown-ether, and is used as a colorimetric reagent of sodium ion. Na⁺ selectivity of this reagent is 6.3 times that of K⁺, and 25 times that of Li⁺. Dr. Nakamura determined the Na⁺ concentration in blood serum using this reagent.
Application:
   Solvent extraction colorimetry: Na (pH 10, 1,2-dichloroethane, lmax=560 nm, e=37,000/detection >6 ppm)

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Product Name: Nitroso-PSAP

Nitroso-PSAP is a highly sensitive water-soluble colorimetric reagent for Fe(II) detection that forms a green complex with Fe(II) (lmax=756 nm, e=4.5x10⁴ ). This reagent is suitable for the determination of blood serum levels of Fe, Co, Ni and Cu. The detection range is from 5 ppb to 5 ppm under the same detection condition. Nitroso-PSAP is useful in flow injection analyses. The workable pH range of the nitroso compounds is 5.6-10.1. The molar absorptivities and maximum wavelengths of the Co, Cu and Ni complexes are 4.0x10⁴ (490 nm), 2.8x10⁴ (429 nm), and 2.6x10⁴ (394 nm), respectively.

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Product Name: NN

NN is a colorimetric and chelatometric reagent for calcium (pH 12, lmax=470 nm) and UO₂²⁺ (lmax=570 nm, e=1.36x10⁵). Although NN is soluble in water, the solution is unstable and decomposes in a few minutes, especially in the presence of oxidative ions. Its proton dissociation constants are reported to be pKa₂=9.26 and pKa₃=13.67 (µ=0.1, 24 ºC). An NN solution of 0.1% w/v in 50% aqueous methanol is stable for one week if stored in a cool and dark place. Ascorbic acid is used as a stabilizer of the NN stock solution. Al, Cu, Fe(III) and Ni interfere with the determination of calcium by NN and should be masked by KCN or triethanolamine.

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Product Name: NN diluted with potassium sulfate

 

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Product Name: o-Phenanthroline

o-Phenanthroline is a colorimetric reagent for iron detection. It is also used as a reagent for the solvent extraction of anions. This reagent is slightly soluble in water (3.3 g/l at room temperature) and benzene (14 g/l at room temperature), and fairly soluble in alcohol (540 g/l), acetone, and diluted mineral acids. Its proton dissociation constants are reported to be pKa₁=0.70 and pKa₂=4.98 (µ=0.1, 25 ºC). o-Phenanthroline forms a red chelate with Fe(II) [logb3=21.1(µ=0.1, 20 ºC), lmax=510 nm, e=1.1x10⁵]. This complex is barely extracted by organic solvents. The reduction and oxidation potential of FeL₃³⁺ -FeL₃²⁺ (L: o-phenanthroline) in 1 M H₂SO₄ is reported to be 1.06 V, and the color of the solution changes from red to pale blue. This reagent also forms colored complexes with Cu, Ni and Co, and colorless complexes with Cd and Zn. Therefore, o-Phenanthroline can be used as a colorimetric reagent for Cu, Ni and Co, and as a masking reagent of Cd and Zn. FeL₃²⁺ is also utilized for precipitation detection and ion-pair extraction.

Applications
Masking: Cd, Zn
Reduction and oxidation indicator: Ce
Colorimetry: Ag, Fe(II) :510 nm, detection limit 0.8 ppm
Fluorometry: Ru(II), Eu
Extraction colorimetry: halogen, ClO₄^-, PtCl₆^2-, ReO₄^-, HCrO₄^-, SCN^-, AuCl₄, Ag(CN)₂^-, Sn(C₂O₄)₃^2-, phosphomolybdate and organic compounds (Trichloroacetic acid, dehydroacetic acid, syclamic acid, saccharin, salicylic acid, alkylbenzenesulfonic acid, maleic acid, pentachlorophenol, tetraphenylborate, and chloranilic acid)

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Product Name: PAN