Eco-friendly high sensitive electrochemical method of luminescence detection
Technical field
The present invention relates to a kind of eco-friendly high sensitive electrochemical luminescent detection techniques field.
Background technology
Electrochemiluminescence is the product that chemiluminescence and electrochemical method mutually combine, be meant by electrochemical method to produce some special materials, further react and a kind of luminescence phenomenon of generation between these electric living beings or between electric living beings and other material then.Electrochemiluminescence analysis method highly sensitive, the range of linearity is wide, and controllability is strong, and selectivity is good, and device is simple, is subjected to people's attention day by day.Nineteen twenty-seven, it is found that the Grignard compound is applied current potential can be produced luminous.During the electrolysis luminol, find all has luminescence phenomenon to nineteen twenty-nine Harvey on negative electrode and anode in alkaline solution, has opened the prelude of electrochemiluminescence research.The eighties is found the luminous mensuration of oxalic acid, aminated compounds, amino acid, NADH, pyruvic acid and the hypersensitive mensuration of pyridine ruthenium of can be used for of pyridine ruthenium electrochemical.During this period, electrochemiluminescence begins to separate the technology coupling with Flow Injection Analysis (FIA), high performance liquid chromatography (HPLC) and Capillary Electrophoresis (CE) etc., has improved the reappearance and the stability of luminous signal, for its practical application is laid a good foundation.The nineties, electrochemiluminescence begin to be used for the Single Molecule Detection of immunoassay, pcr analysis and DNA.Research at present and most widely used be pyridine ruthenium electrochemical luminescence system because it has outstanding advantages such as good water solubility, luminescence efficiency height, stable performance and electrochemical reversible.
The luminesceence analysis of pyridine ruthenium electrochemical is labelled immune analysis of new generation and nucleic acid determination technology.Prior art is based on tripropyl amine (TPA) and the pyridine ruthenium label generation electrochemiluminescence of low concentration of concentration about up to 100mM and reacts and carry out bioanalysis, is that a few is applied to one of electroanalytical technique of practical measurement.But there is following main weak point in pyridine ruthenium/tripropyl amine (TPA) electrochemiluminescsystem system.First and third propylamine oxidation rate on electrode is slower, causes electrochemiluminescence intensity lower, has limited the sensitivity that detects; The second, very the tripropyl amine (TPA) of high concentration could be realized highly sensitive detection; Three, tripropyl amine (TPA) solubleness in neutral solution is not so good, and generally will adopting very, high concentrations of phosphoric acid salt just can make the tripropyl amine (TPA) up to 100mM dissolve in neutral phosphate buffered solution; At last, the tripropyl amine (TPA) volatility is bigger, has bigger peculiar smell and certain toxicity.Therefore pressing for searching has the material of excellent properties more than tripropyl amine (TPA).
The pyridine ruthenium not only can with tripropyl amine (TPA) generation electrochemiluminescence reaction, can also with other a large amount of amine substance electrochemiluminescence rules.First kind of situation is the concentration that bipyridyl ruthenium concentration is close to or higher than amine substance.In this case, the structure of amine is to the more also comparison system of the research of the influence of electrochemiluminescence.At this moment, bipyridyl ruthenium catalytic oxidation amine is very big to electrochemiluminescence contribution, and contain usually the class of electron withdraw group luminous a little less than.Second kind of situation is the concentration of the concentration of bipyridyl ruthenium well below amine.Only there is one piece of document (J.Electrochem.Soc.1990,137,3127) to compare the electrochemiluminescence intensity of several amine roughly at present, but do not sum up luminescence law.This article finds that the electrochemiluminescence intensity of tripropyl amine (TPA) is better than other several amine, and bipyridyl ruthenium/tripropyl amine (TPA) electrochemiluminescsystem system can be used for immunoassay.Many pieces of documents have carried out deep research to the electrochemiluminescence mechanism of bipyridyl ruthenium/tripropyl amine (TPA) system subsequently.Discovery plays important effect (Anal.Chem.2000 in the Direct Electrochemistry oxidation of tripropyl amine (TPA) on electrode under the situation of the concentration of tripropyl amine (TPA) of the concentration of bipyridyl ruthenium, 72.3223), bipyridyl ruthenium catalytic oxidation tripropyl amine (TPA) is less relatively to the electrochemiluminescence contribution.Can strengthen electrochemiluminescence intensity by adding the Direct Electrochemistry oxidations of promotion tripropyl amine (TPA) on electrode such as surfactant.
Summary of the invention
It is bigger to the purpose of this invention is to provide a kind of luminous intensity, sensitive more, and the electrochemical luminescence method friendly more to environment provides the method that is applied to immune electrochemiluminescence analysis and the analysis of other important substance.
The present invention is a kind of eco-friendly high sensitive electrochemical method of luminescence detection, this luminescence system is that the complex compound bipyridyl ruthenium with ruthenium is a luminescent substance, with amine is co-reactant, with the surfactant is improvement reagent, in buffer solution, mix, analyze with the electrochemical method stimulated luminescence, it is characterized in that, the basic structure of co-reactant amine is (R
1) (R
2) N (R
3), R wherein
1, R
2, R
3Be alkyl, and have hydroxyl, carboxyl, amido or sulfonic group at least one alkyl with two to five carbon;
(R of the present invention
1) (R
2) N (R
3) be the di-n-butyl monoethanolamine;
Improvement reagent of the present invention is surfactant, is selected from triton x-100, Tween-20 or sodium dodecylsulphonate; Amine working concentration scope of the present invention is 0.05-50mM; Buffer solution of the present invention is phosphate buffered solution or the borate buffer solution of pH at 5-9;
Potential range of the present invention is 1.1-1.5V.
Outstanding advantage of the present invention be this system luminescence efficiency height, highly sensitive, the range of linearity is wide, the coreaction reagent concentration is low, environmental friendliness, favorable reproducibility and stable reagent.Utilize the range of linearity of this system detection material wide, detectability is low, can be widely used in immunoassay, foranalysis of nucleic acids.The very low and concentration di-n-butyl monoethanolamine of pyridine ruthenium concentration only is under the situation of 20mM, just can realize than adopting the sensitive more detection of tripropyl amine (TPA), under the same terms at pyridine ruthenium/di-n-butyl monoethanolamine on the gold electrode even stronger more than 10 times, strong more than 30 times on the platinum electrode than the intensity of pyridine ruthenium/tripropyl amine (TPA) electrochemiluminescence.
Description of drawings
Accompanying drawing 1 is to utilize pyridine ruthenium/di-n-butyl ethanol system electrochemiluminescence to measure the synoptic diagram of pyridine ruthenium content.
Accompanying drawing 2 is pH synoptic diagram that influence to pyridine ruthenium/di-n-butyl ethanol system electrochemiluminescence.
Accompanying drawing 3 is di-n-butyl concentration of ethanol synoptic diagram that influence to pyridine ruthenium/di-n-butyl ethanol system electrochemiluminescence.
The subordinate list explanation
Table 1 is the luminous intensity contrast that has the various amine of different structure or functional group and the electrochemiluminescsystem system that the pyridine ruthenium is formed.
Amine |
Luminous intensity (a.u.) |
The di-n-butyl monoethanolamine |
381 |
Triethanolamine |
174 |
Tripropyl amine (TPA) |
62 |
N, N-diethyl-N '-methyl ethyleneamines |
28 |
Triacetamide |
21 |
Diethylpropanolamine |
13 |
Embodiment
Embodiment 1: fixedly di-n-butyl monoethanolamine concentration is 25mM, buffer solution is the 0.1M phosphate of pH 7.5, the pyridine ruthenium that adds 1fM, with the gold is working electrode, current potential is got on the rank that apply 1.35V, applies suitable luminous detection high pressure simultaneously, utilizes luminous signal to detect the pyridine ruthenium, replication three times, the mean intensity that obtains pyridine ruthenium luminous signal is 47.41.
Embodiment 2: fixedly di-n-butyl monoethanolamine concentration is 0.05mM, pyridine ruthenium concentration is 1 μ M, buffer solution is the 0.1M phosphate of pH 5, with the gold is working electrode, current potential is got on the rank that apply 1.5V, applies suitable luminous detection high pressure simultaneously, utilizes luminous signal to detect the pyridine ruthenium, replication three times, the luminous signal mean intensity that obtains is 52.4.
Embodiment 3: fixedly the concentration of di-n-butyl monoethanolamine is 1mM, pyridine ruthenium concentration is 1mM, be dissolved in pH9 the 0.1M phosphate buffered solution in, with the gold is working electrode, electrode potential from the 0V cyclic voltammetry scan to 1.1V, apply suitable luminous detection high pressure simultaneously, replication three times, the luminous signal mean intensity that obtains is 1.26 * 10
6
Embodiment 4: fixedly di-n-butyl monoethanolamine concentration is 10mM, pyridine ruthenium concentration is 1 μ M, buffer solution is the 0.1M borate of pH 9, with the gold is working electrode, current potential is got on the rank that apply 1.5V, applies suitable luminous detection high pressure simultaneously, utilizes luminous signal to detect the pyridine ruthenium, replication three times, the luminous signal mean intensity that obtains is 1.1 * 10
6
Embodiment 5: fixedly pyridine ruthenium concentration is 1 μ M, and buffer solution is the 0.1M phosphate of pH 7.5, adds the various amine that contain different structure or functional group, and fixedly the concentration of amine is 25mM.With the gold is working electrode, and assay method is with embodiment 1, every kind of amine replication three times, and its average result is face form 1 as follows.