CN107589085A - It is a kind of to regulate and control nano silicon active absorption spectroscopic assay Hg with aptamers2+Method - Google Patents

Abstract

Regulate and control nano silicon active absorption spectroscopic assay Hg with aptamers the invention discloses one kind²⁺Method, it is characterized in that, comprise the following steps：（1）Prepare the Hg of concentration known²⁺Standard liquid system, it is A to determine its absorbance；（2）Placebo solution system is prepared, it is A to determine its absorbance₀；（3）Calculate Δ A=A A₀；（4）With Δ A to Hg²⁺Concentration relationship work curve；（5）Sample solution is prepared, it is A to determine its absorbance_Sample, calculate Δ A_Sample=A_Sample‑A₀；（6）According to step（4）Working curve, calculate sample solution Hg²⁺Content.Of the invention this assay method need not build the complex process of aptamers nano-probe compared with existing method, and method is easier, quick；Non pinetallic nano enzymatic, high sensitivity, system are more stable.

Description

It is a kind of to regulate and control nano silicon activity-absorption spectromtry Hg with aptamers2+'s Method

Technical field

The present invention relates to analytical chemistry field, is specifically a kind of aptamers regulation and control nano silicon activity-absorption light Spectrum measure Hg²⁺Method.

Background technology

Aptamers are a bit of oligonucleotide sequences obtained through in-vitro screening, can with plurality of target material high specific, High-affinity and combine with high selectivity, when aptamer and target substance are specifically bound, aptamer oneself The configuration of body can change, and its detection signal changes so as to realize the detection to object therewith.Mercury is that toxicity is very strong Heavy metal, mercury is easy to produce enrichment in human body and animal, the particularly Fish by food chain, even if dense at its In the case that degree is very low, mercury can also cause very big, long-term toxic action to human body and environment.Therefore, Trace Hg is studied Assay method is significant.

At present, the assay method of mercury mainly has the gentle Liquid Chromatography-Mass Spectrometry of atomic absorption spectrography (AAS) and with exempting from The method of epidemic disease reaction bonded such as colorimetric method, fluorescent spectrometry, Resonance Rayleigh Scattering Spectral Method, Surface Enhanced Raman Scattering Spectrum Method.In these methods, although atomic absorption spectrography (AAS) instrument is popularized, stability is good, instrument precision is poor；Liquid phase color Spectrum-mass spectrometric hyphenated technique is sensitiveer than atomic absorption spectrography (AAS), has the advantages that the range of linearity is wide, but process is numerous and diverse, cost It is higher, and detection sensitivity depends on detection technique after post；Immune colorimetric method is simple and easy to do, economical, but sensitivity is not good enough；Fluorescence Spectroscopic methodology process is numerous and diverse, and cost is higher；Resonance Rayleigh Scattering Spectral Method it is sensitive, quick, easy biochemistry, analytical chemistry, Nano materials research etc. has application.However, above immunoassay method is substantially according to Hg²⁺With the thymus gland in aptamers Pyrimidine forms T-Hg²⁺- T structures, immunological probe molecule is built, then carries out corresponding experimental method operation again, it is generally speaking real It is all more complicated to test operation.

Nano enzyme is the special performance of a kind of existing nano material, there is the analogue enztme of catalysis again.Nano enzyme, which has, urges Change efficiency high, stably, economy and the characteristics of prepare with scale.Since HRP nano enzymes in 2007 are reported, the research of nano enzyme is fast Speed emerge, research be related to face also gradually extensively, including material science, physics, chemistry, biology, medical science and environment etc. no Same domain.Compared with native enzyme, nano material has the advantages that stability is high, catalytic activity is high and cheap and easy to get, particularly keeps away Exempt from that native enzyme possessed is unstable and mutability feature, added it in process catalysis and the application of enzyme kinetic analysis field Prospect, thus there is the nano material of analogue enztme activity to have great importance in analytical chemistry for these.Nano enzyme is applied to In analytical chemistry, detection of heavy metal ion and biomolecule detection and immunoassay are related generally to, but be based on metal nano Using more, the research for non pinetallic nano enzyme is very few for the research of enzyme.Surface plasma resonance (Surface Plasmon Resonance, SPR) it is irradiated to metal free electron caused by the dielectric surface of different refractivity from critical angle according to incident light Resonance, the interaction specific signals between biomolecule are obtained to carry out qualitative and quantitative analysis to molecular components.Nanometer Silica is increasingly widely used as a kind of new nano material, and it is non-to regulate and control nano silicon using aptamers The catalytic action of metal nano enzyme is applied to quantitative determination Hg with surface plasmon resonance absorption spectral technique²⁺Analysis method still Have no report.

The content of the invention

The purpose of the present invention is for measure Hg²⁺The deficiencies in the prior art, and a kind of aptamers regulation and control nanometer two is provided Silica activity-absorption spectromtry Hg²⁺Method.This method need not build the complex process of aptamers nano-probe, Method is easier, quick；Non pinetallic nano enzymatic, high sensitivity, system are more stable.

Realizing the technical scheme of the object of the invention is：

It is a kind of to regulate and control silicon dioxide activity-absorption spectromtry Hg with aptamers²⁺Method, comprise the following steps：

(1) Hg of concentration known is prepared²⁺Standard liquid system：In scale test tube, 10 μ L-200 μ L are sequentially added 100nmol/L Hg²⁺Standard liquid, 50 μ L-120 μ L 66ng/mL mercury aptamers and the μ g/mL titanium dioxides of 10 μ L-20 μ L 100 Silicon, mix, stand 10 minutes；Then 100 μ L-200 μ L 0.5moL/L glucose, 100 μ L-180 are sequentially added in each test tube μ L 0.01moL/L HCl and 100 84 μm of oL/L HAuCl of μ L-120 μ L₄, mix, 1.5mL is settled to redistilled water, 75 DEG C water-bath 20 minutes, test tube is taken out, cool down terminating reaction with frozen water, 2.0mL is settled to redistilled water；

(2) placebo solution system is prepared：Hg is not added with the method for step (1)²⁺It is molten that standard liquid prepares blank control Liquid system；

(3) Hg by step (1), (2) preparation is taken respectively²⁺Standard liquid system and placebo solution system are poured into colorimetric In ware, on spectrophotometer, instrument parameter slit is set as 5nm, scans the absorption spectrum of acquisition system, is determined at 580nm Absorbance be A, while the absorbance for determining placebo solution system is A₀, calculate Δ A=A-A₀；

(4) with Δ A to Hg²⁺Concentration relationship work curve；

(5) method according to step (1) prepares sample solution, wherein the Hg added²⁺Standard liquid replaces with sample solution, And the absorbance for pressing the method determination sample solution of step (3) is A_Sample, calculate Δ A_Sample=A_Sample-A₀；

(6) working curve according to step (4), calculates sample solution Hg²⁺Content.

The sequence of mercury aptamers described in step (1) is 5 '-TTTCTTCTTTCTTCCCCCCTTGTTTGTTGTTT-3 '.

Realizing the principle of the technical program is：

Under the conditions of the technical program, nano silicon is to glucose-HAuCl₄This reaction of generation golden nanometer particle With stronger catalytic action；When aptamers are adsorbed on silica nanometer enzyme surface, it is suppressed that glucose-HAuCl₄Generation This reaction of golden nanometer particle；When system adds Hg²⁺When, combine to form stable aptamers-Hg with aptamers²⁺Conjugate is simultaneously Depart from from silica nanometer enzyme surface, silica catalytic activity is recovered.With Hg in system²⁺The increase of concentration, titanium dioxide Silicon catalytic activity strengthens, and surface plasmon resonance absorption, absorbance increase occur for the golden nanometer particle of generation.Hg²⁺Concentration with The absorbance enhancement value of system is linear, establishes measure Hg accordingly²⁺Aptamers regulation and control nano silicon activity suction Receive spectrographic technique.

The advantages of this method is：Compared with the existing methods, this assay method need not build aptamers nano-probe Complex process, method is easier, quick；Non pinetallic nano enzymatic, high sensitivity, system are more stable.

Brief description of the drawings

Fig. 1 is the abosrption spectrogram in embodiment.

In figure, a.3.3ng/mL μ g/mL silica+0.75mmoL/L HCl+37.5mmoL/L Portugals of mercury aptamers+0.6 + 4.2 μm of oL/L HAuCl of grape sugar₄b.a+0.5nmoL/L Hg²⁺c.a+2.5nmoL/L Hg²⁺d.a+5nmoL/L Hg²⁺e.a+ 7.5nmoL/L Hg²⁺f.a+10nmoL/L Hg²⁺。

Embodiment

Present invention is further elaborated with reference to embodiment and accompanying drawing, but is not limitation of the invention.

Embodiment：

It is a kind of to regulate and control nano silicon activity-absorption spectromtry Hg with aptamers²⁺Method, comprise the following steps：

(1) Hg of concentration known is prepared²⁺Standard liquid system：In 7 scale test tubes, 10 μ L, 50 μ L are separately added into, 100 μ L, 150 μ L, 200 μ L 100nmol/L Hg²⁺100 μ L are sequentially added in standard liquid and then every scale test tube 66ng/mL mercury aptamers and the μ g/mL silica of 12 μ L 100, mix, stand 10 minutes；Then sequentially added in each test tube 84 μm of 150 μ L 0.5moL/L glucose, 150 μ L 0.01moL/L HCl and 100 μ L oL/L HAuCl₄, mix, with secondary steaming Distilled water is settled to 1.5mL, 75 DEG C of water-baths 20 minutes, takes out test tube, cools down terminating reaction with frozen water, determined with redistilled water Hold to 2.0mL；

(2) placebo solution system is prepared：Hg is not added with the method for step (1)²⁺It is molten that standard liquid prepares blank control Liquid system；

(3) Hg by step (1), (2) preparation is taken respectively²⁺Standard liquid system and placebo solution system are poured into colorimetric In ware, on spectrophotometer, instrument parameter is set, scans the absorption spectrum of acquisition system, determines the absorbance at 580nm For A, while the absorbance for determining placebo solution system is A₀, calculate Δ A=A-A₀；

(4) with Δ I to Hg²⁺Concentration relationship work curve；Acquisition equation of linear regression is Δ A_580nm=0.026C+ 0.035, wherein Hg²⁺The unit of concentration C is nmol/L, and the measure range of linearity is 0.5~10nmoL/L, and detection is limited to 0.09nmol/L；

(5) method according to step (1) prepares sample solution, wherein the Hg added²⁺Standard liquid replaces with sample solution, And the absorbance for pressing the method determination sample solution of step (3) is A_Sample, calculate Δ A_Sample=A_Sample-A₀, fetch from In The Suburbs of Guilin Pond water, the river in area, are filtered with filter paper, measure appropriate filtrate, and the method according to step (1) prepares sample, wherein adding The Hg entered²⁺Standard liquid replaces with sample, is operated by step (2)-(4).Calculate the Δ A of sample_Sample=A_Sample-A₀；

(6) working curve according to step (4), calculates sample solution Hg²⁺Content, the work according to step (4) is bent Line, calculate sample Hg²⁺Content, Hg in pond water²⁺Content is 3.9nmol/L, Hg in river²⁺Content is 5.3nmol/L。

The sequence of mercury aptamers described in step (1) is 5 '-TTTCTTCTTTCTTCCCCCCTTGTTTGTTGTTT-3 '.

The checking of the technical program detection method：

Each three parts of two kinds of water samples in above-described embodiment step (5) are taken, it is 3nmol/L and 5nmol/L to be separately added into concentration Hg²⁺Standard liquid, carry out recovery testu, try to achieve the rate of recovery be respectively 97.7%, 98.4%, 101.2% and 99.3%, 98.5%th, 97.6%, relative standard deviation is 4.7% and 4.9%.

Illustrate the technical scheme accurately and reliably.

Claims (2)

1. a kind of regulate and control nano silicon activity-absorption spectromtry Hg with aptamers²⁺Method, it is characterized in that, including such as Lower step：

(1) Hg of concentration known is prepared²⁺Standard liquid system：In scale test tube, 10 μ L-200 μ L 100nmol/ are sequentially added L Hg²⁺Standard liquid, 50 μ L-120 μ L 66ng/mL mercury aptamers (sequence 5 '- TTTCTTCTTTCTTCCCCCCTTGTTTGTTGTTT-3 ') and the μ g/mL silica of 10 μ L-20 μ L 100, mix, stand 10 Minute；Then 100 μ L-200 μ L 0.5moL/L glucose, 100 μ L-180 μ L 0.01moL/L are sequentially added in each test tube HCl and 100 84 μm of oL/L HAuCl of μ L-120 μ L₄, mix, 1.5mL, 75 DEG C of water-baths 20 be settled to redistilled water Minute, test tube is taken out, terminating reaction is cooled down with frozen water, 2.0mL is settled to redistilled water；

(2) placebo solution system is prepared：Hg is not added with the method for step (1)²⁺Standard liquid prepares placebo solution body System；

(3) Hg by step (1), (2) preparation is taken respectively²⁺Standard liquid system and placebo solution system are poured into cuvette In, on spectrophotometer, instrument parameter slit is set as 5nm, scans the absorption spectrum of acquisition system, is determined at 580nm Absorbance is A, while the absorbance for determining placebo solution system is A₀, calculate Δ A=A-A₀；

(4) with Δ A to Hg²⁺Concentration relationship work curve；

(5) method according to step (1) prepares sample solution, wherein the Hg added²⁺Standard liquid replaces with sample solution, and presses The absorbance of the method determination sample solution of step (3) is A_Sample, calculate Δ A_Sample=A_Sample-A₀；

(6) working curve according to step (4), calculates sample solution Hg²⁺Content.

2. according to claim 1 regulate and control nano silicon activity-absorption spectromtry Hg with aptamers²⁺Method, It is characterized in that the sequence of mercury aptamers described in step (1) is 5 '-TTTCTTCTTTCTTCCCCCCTTGTTTGTTGTTT-3 '.