CN109459420A

CN109459420A - The detection method of two/ferric ion in a kind of water body

Info

Publication number: CN109459420A
Application number: CN201811631214.3A
Authority: CN
Inventors: 赖家平; 冯焕然; 单法硕; 孙慧
Original assignee: South China Normal University
Current assignee: South China Normal University
Priority date: 2018-12-29
Filing date: 2018-12-29
Publication date: 2019-03-12
Anticipated expiration: 2038-12-29
Also published as: CN109459420B

Abstract

The invention belongs to analysis method technical fields, and in particular to the detection method of two/ferric ion in a kind of water body.Present invention finds the fluorescence probes that a kind of pair of ferro element can be carried out Determination of Different Valence States --- and-ellagic acid, the probe have the characteristics that unique sexual clorminance that is low in cost, being easily obtained, and there are most fluorescence probes not have, i.e. the iron ion Fe to two kinds of valence states²⁺And Fe³⁺Have response, form two kinds of complexs, under Tris-HCl buffer solution, can it is qualitative respectively, quantitatively measure Fe²⁺And Fe³⁺Concentration；And Fe is sheltered in tartaric acid diammonium³⁺In the state of, it remains to accurately detect Fe²⁺.Either independent quantitative detection, or masking Fe³⁺In the case where quantitative detection, have good linear relationship between the fluorescent emission intensity and iron concentration of ellagic acid, detection limit is respectively 72nM, 63nM, 76nM.Using this feature, we can be with ellagic acid come the iron ion of different valence state in analyzing water body simultaneously, so that fluorescence analysis has been also employed in Determination of Different Valence States.

Description

The detection method of two/ferric ion in a kind of water body

Technical field

The invention belongs to analysis method technical fields, and in particular to the detection method of two/ferric ion in a kind of water body.

Background technique

Iron not only industrially has important use, but also the highest microelement of abundance in it or human body.As life The highest microelement of abundance in object, iron play an important role in many physiology courses.Iron is not only the weight of hemoglobin Component part is wanted, and it also helps cytochromes to carry out redox transfer electronics.In addition, the important set of iron or azotase At part.But the iron of too high amount will will lead to serious health problem, such as cause cancer and certain organs such as heart, The aging of pancreas and liver, neurogenic disease such as parkinsonism and senile dementia.The intracorporal iron of biology is mainly divalent , minute quantity is trivalent, therefore ferric iron is usually harmful to organism, but the iron in natural water is all exactly trivalent. So find it is a kind of can fast qualitative quantitative detection and Determination of Different Valence States can be made to iron method caused environmental science Concern.

The method of detection iron (or ferrous) ion has colorimetric method, electrochemical methods, high performance liquid chromatography, light splitting at present Photometry, atomic absorption method etc..Although these detection methods have their own advantages, but also have certain deficiency or instrument precision and It is expensive；Or sample composition is more, and interference is big；Or detection limit for height；Or it is cumbersome etc..Therefore these methods above have in application Certain limitation, also most fluorescence probes cannot achieve and carry out Determination of Different Valence States to identity element.

It was found that content

In order to overcome the disadvantages and deficiencies of the prior art, the purpose of the present invention is to provide two/ferric irons in a kind of water body The detection method of ion.

To achieve the above object, this discovery the technical solution adopted is as follows:

The detection method of two/ferric ion in a kind of water body, comprising the following steps:

(1) it takes in a water sample to be measured, hydroxylamine hydrochloride is added thereto, makes the Fe in solution³⁺All it is reduced into Fe²⁺, so Tris-HCl buffer and methanol are added afterwards, obtains solution I, then Na is added into solution I₂EA obtains solution II, detects solution II fluorescent emission intensity, according to F₁=-1099.47c₁+ 4241.78 equation of linear regression calculates the Fe in solution²⁺With Fe³⁺ Total concentration, wherein F₁For fluorescent emission intensity, c₁For Fe²⁺With Fe³⁺Total concentration；

(2) work as Fe²⁺/Fe³⁺When concentration ratio is greater than 0.07, a water sample to be measured is separately taken, tartaric acid diammonium is added thereto, Solution III is obtained, Tris-HCl buffer and methanol are then added into solution III, obtains solution IV, then be added into solution IV Na₂EA obtains solution V, the fluorescent emission intensity of solution V is detected, according to F₂=-1078.43c₂+ 4297.06 linear regression Fe in equation calculation solution²⁺Concentration, then c₂For the Fe in water sample to be measured²⁺Concentration, c₁-c₂For the Fe in water sample to be measured³⁺ Concentration, wherein F₂For fluorescent emission intensity；

Work as Fe²⁺/Fe³⁺When concentration ratio is less than or equal to 0.07, a water sample to be measured is separately taken, Moxifloxacin is added, obtains solution VI, Tris-HCl buffer solution is then added into solution VI, obtains solution VII, the fluorescent emission intensity of detection solution VII is F₃；Moxifloxacin is separately added into distilled water, obtains Moxifloxacin blank solution, detecting its fluorescence intensity is F₀, according to F₀- F₃ =1868.12*c₃ ^1/2Fe in solution is calculated in -467.71 equations of linear regression³⁺Concentration, then c₃For in water sample to be measured Fe³⁺Concentration, c₁-c₃For the Fe in water sample to be measured²⁺Concentration.

It should be noted that since the range of linearity of ellagic acid and Moxifloxacin is inconsistent, it is sometimes desirable to dilute solution I Certain multiple adds ellagic acid after being located in the ellagic acid range of linearity to total concentration of iron, therefore when dilute solution I, according to line Property regression equation F₁=-1099.47c₁+ 4241.78 Fe calculated²⁺Concentration need multiplied by diluted multiple to be only reality The actual concentrations of total iron in sample.

Preferably, solution I described in step (1), in solution IV and solution VII described in step (2), Tris-HCl The concentration of buffer is 0.01M.

Preferably, in solution IV described in solution I described in step (1) and step (2), the volume fraction of methanol is 80%.

Preferably, in solution V described in solution II described in step (1) and step (2), Na₂The concentration of EA is 8 μ M。

Preferably, in solution III described in step (2), the concentration of tartaric acid diammonium is 0.01M.

Preferably, in solution VI described in step (2), the concentration of Moxifloxacin is 2 μM.

Preferably, in Moxifloxacin blank solution described in step (2), the concentration of Moxifloxacin is 2 μM.

Preferably, it is molten that detection described in the fluorescent emission intensity and step (2) of solution II is detected described in step (1) The testing conditions of the fluorescent emission intensity of liquid V are the 5nm exciting slit using 357nm as excitation wavelength, 5nm transmite slit and 700V Under the conditions of Photomultiplier tube voltage, the fluorescent emission intensity in 377~650nm wave-length coverage is recorded.

Preferably, after addition Tris-HCl buffer described in step (1) and methanol and described in step (2) Be added after Tris-HCl buffer and methanol into solution III, the pH for adjusting solution is 5~7.

The Na₂EA is the disodium salt of ellagic acid, and wherein ellagic acid has structural formula as follows:

Preferably, the detection method of two/ferric ion is suitable for Fe in the water body²⁺Or Fe³⁺Concentration 0.08 Water body within the scope of~1.10 μM.

Compared with the prior art, the invention has the following advantages and beneficial effects:

Present invention finds the fluorescence probes that a kind of pair of ferro element can be carried out Determination of Different Valence States --- and-ellagic acid, the probe have Low in cost, the characteristics of being easily obtained, and unique sexual clorminance that there are most fluorescence probes not have, i.e., to two kinds of valence states Iron ion Fe²⁺And Fe³⁺There is response, forms two kinds of complexs, ellagic acid and Fe²⁺Coordination ratio is 1:3, with Fe³⁺Coordination ratio is 1:2.Under the Tris-HCl buffer solution of pH=6.5, can it is qualitative respectively, quantitatively measure Fe²⁺And Fe³⁺Concentration；And in winestone Sour diammonium shelters Fe³⁺In the state of, it remains to accurately detect Fe²⁺.Either independent quantitative detection, or masking Fe³⁺In the case where Quantitative detection has good linear relationship, and the range of linearity is all 0.08~1.1 μM, detection limit be respectively 72nM, 63nM, 76nM.Using this feature, we can be with ellagic acid come the iron ion of different valence state in analyzing water body simultaneously, so that fluorescence point Analysis method has been also employed in Determination of Different Valence States.

Detailed description of the invention

Fig. 1 is the fluorescent emission intensity figure of the solution containing different metal ions in embodiment 1.

Fig. 2 is the fluorescent emission intensity figure of four kinds of Methanol-water phase solution in embodiment 1.

Fig. 3 is in embodiment 1 under different methanol volume fractions, blank solution and contains Fe²⁺、Fe³⁺The fluorescent emission of solution Intensity contrast figure；Wherein, continuous three cylindricalitys are one group, and corresponding identical methanol volume fraction, three cylindricalitys are from left to right It is corresponding in turn to EA, EA+Fe³⁺、EA+Fe²⁺Solution.

In the presence of Fig. 4 is single interfering ion in embodiment 2, it is added without Fe²⁺Or Fe³⁺, and Fe is added²⁺With Fe³⁺Solution fluorescent emission intensity；Wherein, continuous three cylindricalitys are one group, corresponding identical interfering ion, three cylindricalitys From left to right it is corresponding in turn to EA+ interfering ion, EA+ interfering ion+Fe³⁺, EA+ interfering ion+Fe²⁺Solution.

Fig. 5 is in the presence of mixing interfering ion in embodiment 2, to be added without Fe²⁺Or Fe³⁺, and Fe is added²⁺With Fe³⁺Solution fluorescent emission intensity figure；4 curves be from top to bottom corresponding in turn to EA, EA+ interfering ion, EA+ interfering ion+ Fe²⁺, EA+ interfering ion+Fe³⁺Solution.

Fig. 6 is the fluorescent emission intensity figure of solution under different pH value in embodiment 3.

Fig. 7 is the fluorescent emission intensity and Fe of 4 middle probe EA of embodiment²⁺Concentration linear relationship figure.

Fig. 8 is the fluorescent emission intensity and Fe of 4 middle probe EA of embodiment³⁺Concentration linear relationship figure.

Fig. 9 is to shelter Fe in embodiment 4³⁺When probe EA fluorescent emission intensity and Fe²⁺Concentration linear relationship figure.

Figure 10 is in embodiment 5 for determining probe EA and Fe²⁺Between stoichiometric ratio Job ' s plot analysis chart.

Figure 11 is in embodiment 5 for determining probe EA and Fe³⁺Between stoichiometric ratio Job ' s plot analysis chart.

Specific embodiment

Below with reference to embodiment, the present invention is described in further detail, and embodiments of the present invention are not limited thereto. For not specifically specified technological parameter, routine techniques progress can refer to.

The reagent and instrument that the following example uses are as follows:

Reagent:

Ellagic acid (analyzes pure, Shanghai Mike's woods reagent Co., Ltd)

The tertiary butantriol of amino (99.9%, Shanghai Sangon Biological Engineering Technology And Service Co., Ltd)

Methanol (analyzes pure, Chengdu Ke Long chemical reagent factory)

Tartaric acid (analyzes pure, Shanghai Mike's woods reagent Co., Ltd)

Tartaric acid diammonium (analyzes pure, Shanghai Mike's woods reagent Co., Ltd)

Hydrochloric acid (analyzes pure, Chengdu Ke Long chemical reagent factory)

Various aqueous metallic ions (including Al³⁺、Be²⁺、Ba²⁺、Li⁺、Mg²⁺、Cu²⁺、Cd²⁺、Co2+、Pb²⁺、Ag⁺、Cr³ ⁺、Ni²⁺、Zn²⁺、Mn²⁺、Hg²⁺、Fe²⁺、Fe³⁺) be made by its corresponding nitrate or hydrochloride and (analyze pure, Shanghai Aladdin Reagent)

Tris-HCl and the Tris- tartaric acid buffer solution of each pH value, by the tertiary butantriol of amino and hydrochloric acid or amino Tertiary butantriol and tartaric acid are made；

In addition to having specified otherwise, used reagent is that analysis is pure；Used water is deionized water；All examinations Agent is bought from commercial supplier, no longer purified use.

Instrument:

Assay balance (FA2004B, Shanghai Tian Mei balance equipment Co., Ltd)

Sepectrophotofluorometer (FL-2700, Japanese Hitachi company)

PH meter (PHS-3C, Shanghai Precision & Scientific Instrument Co., Ltd. Leici Instrument Factory)

Eddy mixer (XW -80A, Industrial Co., Ltd., upper Nereid section)

50 μ L/100 μ L/1mL/5mL liquid-transfering guns (Beijing big dragon Xing Chuan laboratory apparatus Co., Ltd)

Miillpore filter (water system, diameter 50mm, 0.2 μm of aperture saliva rise micropore filtering film)

Embodiment 1

The present embodiment provides selective inquiry experiment and methanol volume fraction of the EA to metal ion to detect metal to EA The influence inquiry experiment of ionic consequences.

With pH=7.0, the Tris-HCl buffer solution that concentration is 0.01M is solvent, the Na that preparation concentration is 8 μM₂EA is molten Then 1 times of equivalents of metal ion Al is added in liquid into solution respectively³⁺、Be²⁺、Ba²⁺、Li⁺、Mg²⁺、Cu²⁺、Cd²⁺、Co²⁺、Pb²⁺、 Ag⁺、Ni²⁺、Zn²⁺、Fe²⁺、Fe³⁺、Mn²⁺、Cr³⁺、Hg²⁺, while it being prepared for blank solution to be measured, measure the fluorescence hair of each solution The variation of intensity is penetrated, as a result as shown in Figure 1.

As seen from Figure 1, Fe²⁺With Fe³⁺To Na₂EA solution has apparent fluorescence quenching, Cr³⁺Also there is part Quenching effect.The result shows that Na₂EA solution is to Fe²⁺And Fe³⁺There is good selectivity, removes Cr³⁺Have outside some interference, other Ion is noiseless, therefore only needs to eliminate Cr³⁺Interference.The analysis found that Fe²⁺And Fe³⁺Make Na₂The fluorescence of EA occurs Quenching be because sour phenol lactone ketonic oxygen and phenolic hydroxyl group respectively with Fe²⁺And Fe³⁺Complex effect has occurred, because of Cr³⁺And Fe³⁺ Structure has some similitudes, therefore also makes Na in water phase liquid system₂EA fluorescent quenching.

In order to eliminate Cr³⁺Interference, Xiang Shangshu Na₂Methanol is added in EA solution, makes the volume overall solution volume of methanol 66.67%, as detection solution, then respectively detect blank solution, be added Fe²⁺Solution, be added Fe³⁺Solution and plus Enter equivalent equivalent Cr³⁺Solution fluorescence intensity, as a result as shown in Figure 2.

As shown in Figure 2, after methanol being added, Cr³⁺Interference can eliminate.

In order to probe into optimal methanol volume fraction, the volume for having prepared methanol accounts for overall solution volume 50%, 60% respectively, 70%, 80%, 90%, 95% EA, EA+Fe³⁺、EA+Fe²⁺Solution, EA and Fe in solution²⁺、Fe³⁺Concentration be 8 μM, survey The fluorescence intensity of fixed each solution, as a result as shown in Figure 3.

From figure 3, it can be seen that containing Fe when methanol volume fraction is not less than 50%²⁺、Fe³⁺The fluorescence intensity of solution all compare It is closer to, also all relatively, but methanol volume fraction is at 80% for the fluorescence intensity of blank solution, blank solution and contains Fe²⁺、Fe³⁺The fluorescence intensity difference of solution reaches peak.

Embodiment 2

The present embodiment provides the anti-interference researchs with EA fluorescence probe detection two/ferric ion process.

In order to probe into Na₂EA is in entity water sample to Fe²⁺With Fe³⁺Whether there is practical detection, needs to examine other metals Ion (Al³⁺、Be²⁺、Ba²⁺、Li⁺、Mg²⁺、Cu²⁺、Cd²⁺、Co²⁺、Pb²⁺、Ag⁺、Cr³⁺、Ni²⁺、Zn²⁺、Mn²⁺、Hg²⁺) to measurement Fe² ⁺With Fe³⁺Interference.Therefore, in pH=7.0, the concentration of Tris--HCl buffer solution is 0.01M and methanol volume fraction is In 80% detection solution, Na is worked as in detection₂When EA and interference concentration of metal ions are all 32 μM, it is added without Fe²⁺Or Fe³⁺, and Fe is added²⁺(concentration is 8 μM) and Fe³⁺The fluorescent emission intensity of the solution of (concentration is 8 μM), as a result as shown in Figure 4.

As can be seen from Figure 4,4 times of equivalents of any single coexisting ion do not interfere the fluorescent quenching of EA, i.e., single The presence of mutual interference ion is to EA and Fe²⁺、Fe³⁺Coordination effect do not have an impact.This demonstrate that EA is to Fe²⁺、Fe³⁺Choosing Selecting property is not affected by influence.

In order to probe into hybrid ionic whether can to selectivity interfere, devised in experiment above-mentioned 15 kinds of interfering ions with Fe²⁺、Fe³⁺Mixed solution.Prepare Na₂When EA and hybrid ionic concentration are all 8 μM, detection is added without Fe²⁺Or Fe³⁺, Yi Jijia Enter Fe²⁺(concentration is 8 μM) and Fe³⁺The fluorescent emission intensity of the solution of (concentration is 8 μM), as a result as shown in Figure 5.

As can be seen from Figure 5, the solution containing 15 kinds of hybrid ionics is close with the fluorescence intensity of blank solution, but Fe is added²⁺ Or Fe³⁺Afterwards, fluorescence intensity still obviously quenches.The result shows that: common mixed metal ion pair Na₂EA measures Fe²⁺And Fe³⁺? It is noiseless.

Embodiment 3

The present embodiment provides pH value to detect Fe to EA²⁺And Fe³⁺Influence research.

Since pH value is to Fe²⁺And Fe³⁺And the existence form of EA has a significant effect, then influence EA fluorescent emission intensity and Fe²⁺And Fe³⁺Testing result, therefore following probe into has been done in influence of this experiment to pH value.In the concentration of Tris-HCl buffer solution In the detection solution that volume fraction for 0.02M and methanol is 80%, when pH value is respectively 1.5,2.0,2.5,3.0,3.5, 4.0,4.5,5.0,5.5,6.0,6.5 and 7.0, and Na₂EA and Fe²⁺、Fe³⁺Concentration when being all 8 μM, survey the fluorescence of different solutions Emissive porwer variation, as a result as shown in Figure 6.

As seen from Figure 6, when pH value is 2.5~5.0, fluorescent emission intensity starts sudden with the increase of pH value It goes out；When pH is 5.0~7.0, Fe is added²⁺Or Fe³⁺The fluorescent emission intensity of EA obviously quenches and stablizes afterwards.

Embodiment 4

The present embodiment provides Fe²⁺And Fe³⁺Quantitative detection research.

(1)Fe²⁺And Fe³⁺Independent quantitative detection

In order to probe into EA and Fe²⁺With Fe³⁺Whether quantitative relationship is had, in pH=6.5, Tris-HCl buffer concentration is In the detection solution that 0.01M and methanol volume fraction are 80%, devising a series of EA concentration is 8 μM and Fe²⁺、Fe³⁺Concentration point Wei not be 0.08 μM, 0.09 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.4 μM, 0.5 μM, 0.6 μM, 0.7 μM, 0.8 μM, 0.9 μM, 1.0 μ M, 1.1 μM of mixed liquor, then using 357nm as excitation wavelength, 5nm exciting slit, 5nm transmite slit, 700V photomultiplier tube Voltage measures the fluorescent emission intensity variation of blank sample and mixed liquor, as a result as illustrated in figs. 7 and 8.

It can be seen that by Fig. 7 and 8, the fluorescent emission intensity of probe EA is with Fe²⁺With Fe³⁺The increase of concentration and quench, and Fe² ⁺With Fe³⁺Concentration is the fluorescent emission intensity and Fe of probe EA at 0.08~1.10 μM²⁺With Fe³⁺It is in a linear relationship.? Its equation of linear regression is respectively F=-1099.47c+4241.78 (R²=0.9985) and F=-1080c+4108.52 (R²= 0.9987), in formula, F indicates fluorescent emission intensity, and c indicates Fe²⁺Or Fe³⁺Concentration (unit: μM).When signal-to-noise ratio is 3, According to formula: 3 σ/k show that its detection is limited to 72nM and 63nM.Due to Fe³⁺When pH value is greater than 4, hydrolysis degree is larger, therefore glimmering The quenching degree of light is compared with Fe²⁺Low, i.e., amplitude is compared with Fe²⁺It is unobvious.

(2)Fe²⁺And Fe³⁺Fe is sheltered when coexisting³⁺Under the premise of to Fe²⁺Quantitative detection

In order to probe into Fe²⁺And Fe³⁺Whether EA remains to Fe when coexisting²⁺Quantitative detection is carried out, in pH=6.5, Tris- wine In the detection solution that stone acid buffer concentration is 0.01M and methanol volume fraction is 80%, devising a series of EA concentration is 8 μ M、Fe³⁺Concentration is 1.1 μM and Fe²⁺Concentration is respectively 0.08 μM, and 0.09 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.4 μM, 0.5 μM, 0.6 μM, 0.7 μM, 0.8 μM, 0.9 μM, 1.0 μM and 1.1 μM of mixed liquor, using 357nm as excitation wavelength, 5nm exciting slit, 5nm transmite slit, 700V Photomultiplier tube voltage are measured without Fe²⁺Solution 10 times, mixing various concentration Fe²⁺Solution is each put down Row 3 times, record fluorescent emission intensity variation, as a result as shown in Figure 9.

As seen from Figure 9, the fluorescent emission intensity of probe EA is with Fe²⁺The increase of concentration and quench, and Fe²⁺Concentration At 0.08~1.10 μM, the fluorescent emission intensity and Fe of probe EA²⁺It is in a linear relationship.Obtaining its equation of linear regression is F=- 1078.43c+4297.06(R²=0.9962), in formula, F indicates fluorescent emission intensity, and c indicates Fe²⁺Concentration (unit: μM). When signal-to-noise ratio is 3, according to formula: 3 σ/k show that its detection is limited to 76nM, while also demonstrating tartaric acid to shelter Fe³⁺ And masking effect is good, and [Fe (C₄H₄O₆)₃]^3-Presence do not generate excessive interference to testing result.

Embodiment 5

The present embodiment provides EA and Fe²⁺And Fe³⁺Proportion probe into.

EA and Fe²⁺And Fe³⁺Proportion inquire into using Job ' s plot method, control compound EA and Fe²⁺, EA with Fe³⁺Total concentration be 10 μM it is constant, prepare compound EA and Fe²⁺, EA and Fe³⁺Concentration than be respectively 1:9,2:8,3:7,4: 6,5:5,6:4,7:3,8:2,9:1, so that Fe²⁺、Fe³⁺10wt.%, the 20wt.% of the total concentration of respective system are accounted for respectively, 30wt.%, 40wt.%, 50wt.%, 60wt.%, 70wt.%, 80wt.%, 90wt.%, 100wt.%.Take fluorescence enhancement value (F-F₀) it is ordinate, Fe²⁺、Fe³⁺The specific gravity for accounting for total concentration is abscissa, as a result such as Figure 10 (Fe²⁺), Figure 11 (Fe³⁺) shown in. By this two width figure it is found that Fe²⁺For, it is F-F near 0.75 in ratio₀Reach maximum value；To Fe³⁺For, it is in ratio Near 0.66, F-F₀Reach maximum value.Work as F-F₀When reaching maximum value, coordination is maximum, so EA and Fe²⁺Coordination ratio be 1:3, With Fe³⁺Coordination ratio be 1:2.

Embodiment 6

The present embodiment provides a kind of Fe²⁺/Fe³⁺When concentration ratio is greater than 0.07, iron concentration in tap water and Pearl River water Detection method.

Due to unsuitable iron contamination water source, the present embodiment is by adding iron into tap water and Pearl River water The method of ion simulates contaminated water source to be measured.Detailed process is as follows:

The preparation of water sample to be measured: with tap water and Pearl River water for two groups of basis water bodys, Fe is added into every group of basis water body² ⁺、Fe³⁺Titer makes every group of basis water body be divided into only Fe²⁺, only Fe³⁺With while comprising Fe²⁺、Fe³⁺3 kinds of water samples to be measured. Every kind of water sample to be measured is divided into different 3 of iron concentration again, makes the Fe in 3 water samples to be measured²⁺/Fe³⁺Concentration is respectively 0.2, 0.5 and 1.0 μM.

Take above-mentioned only Fe²⁺And Fe²⁺Concentration is respectively 0.2,0.5 and 1.0 μM of water sample to be measured, and it is slow that Tris-HCl is added The volume fraction of fliud flushing and methanol, the concentration 0.01M and methanol that make Tris-HCl buffer in entire solution is 80%, then to Na is added in water₂EA makes Na in entire solution₂The concentration of EA is 8 μM.The fluorescent emission intensity for detecting all water samples to be measured, according to Equation of linear regression F=-1099.47c+4241.78 (Fe²⁺) Fe in water sample is calculated²⁺Detectable concentration is removed with detectable concentration Fe is calculated with normal concentration (0.2,0.5 and 1.0 μM)²⁺The rate of recovery, the results are shown in Table 1.For Fe²⁺、Fe³⁺It coexists Solution, when addition hydroxylamine hydrochloride is by Fe³⁺It is reduced into Fe²⁺Afterwards, Fe is all in solution²⁺, and verified ellagic acid can for the present embodiment To single Fe²⁺Fe in solution²⁺Concentration is detected, therefore also indirect proof can detect to obtain the result by ellagic acid Fe²⁺、Fe³⁺The full concentration of iron in solution coexists, and the rate of recovery is 80%~120%.

Take above-mentioned only Fe³⁺And Fe³⁺Concentration is respectively 0.2,0.5 and 1.0 μM of water sample to be measured, and it is slow that Tris-HCl is added The volume fraction of fliud flushing and methanol, the concentration 0.01M and methanol that make Tris-HCl buffer in entire solution is 80%, then to Na is added in water₂EA makes Na in entire solution₂The concentration of EA is 8 μM.The fluorescent emission intensity for detecting all water samples to be measured, according to Equation of linear regression F=-1080c+4108.52 (Fe³⁺) Fe in water sample is calculated³⁺Detectable concentration, with detectable concentration divided by mark Fe is calculated in quasi- concentration (0.2,0.5 and 1.0 μM)³⁺The rate of recovery, the results are shown in Table 1.

It takes above-mentioned while including Fe²⁺、Fe³⁺And Fe²⁺Concentration is respectively 0.2,0.5 and 1.0 μM and Fe³⁺Concentration is all 1.1 μM water sample to be measured, be added tartaric acid diammonium, make the concentration 0.01M of entire solution mesotartaric acid diammonium, Tris- be then added The volume fraction of HCl buffer and methanol, the concentration 0.01M and methanol that make Tris-HCl buffer in entire solution is 80%, then Na is added into water₂EA makes Na in entire solution₂The concentration of EA is 8 μM.Detect the fluorescent emission of all water samples to be measured Intensity, according to equation of linear regression F=-1078.43c+4297.06 (Fe²⁺, shield Fe³⁺) Fe in water sample is calculated²⁺Inspection Concentration is surveyed, Fe is calculated divided by normal concentration (0.2,0.5 and 1.0 μM) with detectable concentration²⁺The rate of recovery, as a result such as 1 institute of table Show.

It should be noted that as shielding Fe³⁺When, Fe²⁺Detection rate of recovery when being still located at 80%~120%, can illustrate Ellagic acid can be to Fe²⁺、Fe³⁺The Fe in solution coexists²⁺Concentration is detected.Pass through since above-described embodiment is verified Ellagic acid detects to obtain Fe²⁺、Fe³⁺It coexists the full concentration of iron in solution, and the rate of recovery is 80%~120%, therefore passes through full iron Concentration subtracts Fe²⁺Concentration further can accurately obtain Fe²⁺、Fe³⁺The Fe in solution coexists³⁺Concentration.

Table 1

As can be seen from Table 1, Fe in detection tap water and Pearl River water is carried out in aforementioned manners²⁺/Fe³⁺When, the rate of recovery is located at 81.15 between~116.43%.Wherein individually detect Fe²⁺The rate of recovery is between 87.34~105.46%, Fe³⁺It is located at Between 81.15~112.96%, Fe is sheltered³⁺Survey Fe²⁺When, Fe²⁺The rate of recovery is between 86.88~116.43%.Prove fluorescence Probe ellagic acid provides a kind of highly selective Fe²⁺、Fe³⁺Detection method.

Embodiment 7

The present embodiment provides a kind of Fe²⁺/Fe³⁺When concentration ratio is less than or equal to 0.07, the detection of iron concentration in Pearl River water Method.

Moxifloxacin is to Fe³⁺Quantitative detection

Using 295nm as excitation light source, excitation voltage is that 700V carries out the following fluorescent scanning tested.It is husky toward 2 μM of Moses Fe is gradually added dropwise in star aqueous solution³⁺Solution, with Fe³⁺Concentration increase (ferric ion concentration is successively from bottom to top are as follows: 0, 0.05,0.125,0.25,0.375,0.50,0.75,1.00,1.25,1.50,1.75,2.00,2.50,3.00,3.75,5.00, 7.50,12.50,15.00,20.00,25.00and 30.00 μM), apparent variation has occurred in the fluorescent emission intensity of solution, Fluorescence intensity is with Fe³⁺Concentration increase and gradually weaken.Taking the fluorescent emission intensity at fluorescence intensity highest point is vertical sit Mark, Fe³⁺Concentration is that abscissa obtains conic section.With the conic section relationship of Origin software fitting between the two, song is obtained Line equation Δ F=1868.12*c^1/2-467.71(Fe³⁺)。

The side for passing through the addition iron ion into Pearl River water due to unsuitable iron contamination water source, the present embodiment Method simulates contaminated water source to be measured.Detailed process is as follows:

Fe is added into Pearl River water²⁺、Fe³⁺Titer makes in water while comprising Fe²⁺And Fe³⁺, and Fe²⁺Concentration be 0.08 μM, Fe³⁺Concentration be 1.2 μM, 3.6 μM, 10.8 μM respectively, as water sample to be measured.Moxifloxacin is added, obtains Moses's sand Then Tris-HCl buffer solution is added in the solution that star concentration is 2 μM, obtaining Tris-HCl buffer concentration is 0.01M's Solution, the fluorescent emission intensity for detecting solution is F；Moxifloxacin is separately added into Pearl River water, it is husky to obtain the Moses that concentration is 2 μM Star blank solution, detecting its fluorescence intensity is F₀, according to F₀- F=1868.12*c^1/2- 467.71 equations of linear regression calculate The Fe into solution³⁺Detectable concentration c be respectively 1.02 μM, 4.00 μM, 12.44 μM, with detectable concentration divided by 1.2 μ of normal concentration M, 3.6 μM, 10.8 μM, are calculated Fe³⁺The rate of recovery be respectively 85.00%, 111.11%, 115.19%.Due to embodiment 6 It is verified to detect to obtain Fe by ellagic acid²⁺、Fe³⁺Coexist the full concentration of iron in solution, and the rate of recovery 80%~ 120%, therefore the Fe that the present embodiment obtains is subtracted by full concentration of iron³⁺Concentration further can accurately obtain Fe²⁺、Fe³⁺Altogether Deposit the Fe in solution²⁺Concentration.

The above embodiment is a preferred embodiment of the present invention, but embodiments of the present invention are not by above-described embodiment Limitation, other any changes, modifications, substitutions, combinations, simplifications made without departing from the spirit and principles of the present invention, It should be equivalent substitute mode, be included within the scope of the present invention.

Claims

1. the detection method of two/ferric ion in a kind of water body, which comprises the following steps:

(1) it takes in a water sample to be measured, hydroxylamine hydrochloride is added thereto, makes the Fe in solution³⁺All it is reduced into Fe²⁺, then plus Enter Tris-HCl buffer and methanol, obtains solution I, then Na is added into solution I₂EA obtains solution II, detection solution II Fluorescent emission intensity, according to F₁=-1099.47c₁+ 4241.78 equation of linear regression calculates the Fe in solution²⁺With Fe³⁺It is total Concentration, wherein F₁For fluorescent emission intensity, c₁For Fe²⁺With Fe³⁺Total concentration；

(2) work as Fe²⁺/Fe³⁺When concentration ratio is greater than 0.07, a water sample to be measured is separately taken, tartaric acid diammonium is added thereto, obtains molten Then Tris-HCl buffer and methanol are added into solution III, obtains solution IV, then Na is added into solution IV for liquid III₂EA, Solution V is obtained, the fluorescent emission intensity of solution V is detected, according to F₂=-1078.43c₂+ 4297.06 equation of linear regression meter Calculate the Fe in solution²⁺Concentration, then c₂For the Fe in water sample to be measured²⁺Concentration, c₁-c₂For the Fe in water sample to be measured³⁺Concentration, Wherein, F₂For fluorescent emission intensity；

Work as Fe²⁺/Fe³⁺When concentration ratio is less than or equal to 0.07, a water sample to be measured is separately taken, Moxifloxacin is added, obtains solution VI, so Tris-HCl buffer solution is added in backward solution VI, obtains solution VII, the fluorescent emission intensity of detection solution VII is F₃；Separately to Moxifloxacin is added in distilled water, obtains the Moxifloxacin blank solution that concentration is 2 μM, detecting its fluorescence intensity is F_0,According to F₀- F₃=1868.12*c₃ ^1/2Fe in solution is calculated in -467.71 equations of linear regression³⁺Concentration, then c₃For water sample to be measured In Fe³⁺Concentration, c₁-c₃For the Fe in water sample to be measured²⁺Concentration.

2. the detection method of two/ferric ion in water body according to claim 1, it is characterised in that: institute in step (1) In solution VII described in solution IV described in the solution I stated, step (2) and step step (2), Tris-HCl buffer Concentration is 0.01M.

3. the detection method of two/ferric ion in water body according to claim 1, it is characterised in that: institute in step (1) In solution IV described in the solution I and step (2) stated, the volume fraction of methanol is 80%.

4. the detection method of two/ferric ion in water body according to claim 1, it is characterised in that: institute in step (1) In solution V described in the solution II and step (2) stated, Na₂The concentration of EA is 8 μM.

5. the detection method of two/ferric ion in water body according to claim 1, it is characterised in that: institute in step (2) In the solution III stated, the concentration of tartaric acid diammonium is 0.01M.

6. the detection method of two/ferric ion in water body according to claim 1, it is characterised in that: institute in step (2) In the solution VI and Moxifloxacin blank solution stated, the concentration of Moxifloxacin is 2 μM.

7. the detection method of two/ferric ion in water body according to claim 1, it is characterised in that: institute in step (1) The detector bar of the fluorescent emission intensity of detection solution V described in the fluorescent emission intensity and step (2) of the detection solution II stated Part is the 5nm exciting slit using 357nm as excitation wavelength, under the conditions of 5nm transmite slit and 700V Photomultiplier tube voltage, record Fluorescent emission intensity in 377~650nm wave-length coverage.

8. the detection method of two/ferric ion in water body according to claim 1, it is characterised in that: institute in step (1) It is slow that Tris-HCl is added after the addition Tris-HCl buffer and methanol stated and described in step (2) into solution III After fliud flushing and methanol, the pH for adjusting solution is 5~7.

9. the detection method of two/ferric ion in water body according to claim 1, which is characterized in that the Na₂EA For the disodium salt of ellagic acid, wherein ellagic acid has structural formula as follows:

10. the detection method of two/ferric ion in water body according to claim 1, it is characterised in that: the water body In two/ferric ion detection method be suitable for Fe²⁺Or Fe³⁺Water body of the concentration within the scope of 0.08~1.10 μM.