A method for constructing a ternary logic gate based on fluorescent response of a Mn coordination polymer and output mode conversion

Abstract

The application discloses a ternary logic gate construction and output mode conversion method based on coordination polymer fluorescence response, and belongs to the technical field of fluorescent molecular logic devices. In view of the problem that the existing fluorescence response logic gate can only realize binary output, the operation mode is single, and ternary output and mode conversion cannot be carried out, the application takes Mn(II) coordination polymer (Mn(II)-CP) with stable fluorescence performance as a sensing material, and constructs a fluorescence system with multi-stage fluorescence response by using the fluorescence quenching effect of MnO4 − , the fluorescence enhancement effect of ascorbic acid (AA) and the oxidation-reduction effect of the two. The system can realize three stable states of fluorescence off, conventional on and super-enhanced on in sequence, relies on the gradient fluorescence response characteristics, respectively establishes two sets of assignment rules, successfully constructs two molecular logic gates of ternary (0, 1, 2) and ternary (-1, 0, 1), and can realize the mutual conversion of the two output modes. Experiments show that the system has good linear relationship for AA detection and low detection limit, and the Mn(II)-CP can be regenerated and used repeatedly after simple treatment. The application breaks through the limitation of the traditional binary output of the fluorescence logic gate, improves the logic operation dimension and functional flexibility, and is suitable for a wider application scene, and provides a new scheme for the design and application of multi-ary fluorescent molecular logic devices.

Description

Technical Field

[0001] This invention relates to the fields of fluorescence sensing and molecular computing, specifically a method for constructing and converting the output mode of a ternary logic gate based on the fluorescence response of a Mn(II) coordination polymer. Background Technology

[0002] In existing technologies, coordination polymers possess stable fluorescence emission properties, initially exhibiting fluorescence on or enhanced (turn-on) states. When a specific analyte is added to the coordination polymer system, the analyte can interfere with the luminescence of the coordination polymer through intermolecular interactions, energy competitive absorption, resonant energy transfer, and photoinduced electron transfer, causing the fluorescence of the coordination polymer to quench or decrease (turn-off). Subsequently, an appropriate recovery agent is introduced into the system. This recovery agent can interact with the analyte in the system through redox reactions, sparingly soluble salt precipitation reactions, coordination reactions, etc., effectively eliminating or weakening the influence of the analyte on the fluorescence emission of the coordination polymer, thus restoring the fluorescence of the coordination polymer and ultimately achieving an on-off-on response of the coordination polymer fluorescence signal. Currently, all coordination polymer fluorescence logic gates are constructed based on the aforementioned response mechanism to create a binary logic operation system. Their signal definition method is unified: the analyte and the reconstitute are used as two input signals; adding the substance to the system is defined as input signal "1", and not adding it is defined as input signal "0". The fluorescence state of the coordination polymer is used as the output signal; the fluorescence-on state corresponds to output signal "1", and the fluorescence-quenched state corresponds to output signal "0", thus completing the logical output of a binary (0,1) signal. Furthermore, the reconstitute selected in the existing technology does not significantly affect the fluorescence performance of the coordination polymer itself; it only achieves fluorescence signal modulation through interaction with the analyte. However, existing publicly available coordination polymer fluorescence-responsive logic gate technologies can only achieve binary (0,1) logic output and operation modes, with limited functionality. They cannot overcome the limitations of binary logic, making it difficult to construct ternary logic output systems, and they lack the ability to convert between output modes. Therefore, there is an urgent need to propose a coordination polymer fluorescence logic gate technology capable of constructing ternary logic gates and switching modes, in order to overcome the limitations and defects of existing technologies.

[0003] The basic materials and fluorescent responsive carriers of this invention are derived from the applicant's previously published research (Dyesand Pigments 2026, 246: 113390). This published literature reports a Mn(II) coordination polymer (Mn(II)-CP)Mn3( L The preparation of 4(4,4ʹ-bipy)2(H2O)2⋅Mn(4,4ʹ-bipy)2(H2O)2⋅4H2O, wherein H2L = 4,4'-azobis(2-hydroxybenzoic acid), 4,4ʹ-bipyridine, and the fluorescence-enhancing effect of ascorbic acid (AA), MnO4 − The fluorescence quenching effect of this substance was investigated. These results provide the existing material and technological basis for the selection of materials and the construction of redox fluorescence response systems in this invention. Summary of the Invention

[0004] To address the limitations of existing fluorescence-responsive logic gates based on coordination polymers, which can only achieve binary (0, 1) outputs, have a single mode, and cannot perform ternary logic operations or convert between different ternary output modes, this invention aims to provide a method for constructing ternary logic gates based on the fluorescence response of coordination polymers and a method for output mode conversion. This invention overcomes the limitations of traditional on-off-on fluorescence systems' binary logic, achieving ternary (0, 1, 2) logic outputs, while simultaneously enabling mutual conversion between ternary (-1, 0, 1) output modes. This solves the technical problems of existing fluorescence logic gates, such as low operational dimensionality, single function, and limited applicability.

[0005] This invention utilizes the existing publicly disclosed Mn(II) coordination polymer (Mn(II)-CP) with stable fluorescence emission properties to coordinate MnO4. − Based on the fluorescence response characteristics of ascorbic acid (AA), and further utilizing the novel fluorescence response characteristics of this system, a fluorescent ternary output molecular logic gate was constructed, breaking through the limitation of traditional on-off-on fluorescence responses that can only achieve binary output. Mn(II)-CP exhibits stable fluorescence emission and is in a fluorescence-turn-on state; MnO4 − It has a significant fluorescence quenching effect on Mn(II)-CP, causing MnO4 to... − The Mn(II)-CP system is in a fluorescence-turn-off state; towards MnO4 − After quantitatively adding AA solution to the Mn(II)-CP system, AA reacts with MnO4. − A redox reaction occurs, gradually eliminating MnO4. − The fluorescence turn-off effect of Mn(II)-CP is restored, bringing Mn(II)-CP to a fluorescence turn-on state; MnO4 − After complete reduction, with the continued addition of AA, AA enhances the fluorescence of Mn(II)-CP, making the fluorescence intensity of the system higher than the initial fluorescence intensity of Mn(II)-CP, thus achieving a turn-on fluorescence enhancement. plus The system achieved an on-off-on-on fluorescence state. plus response. Because MnO4− It has strong oxidizing properties and selectively reacts with AA, which has reducing properties, to eliminate MnO4. − The fluorescence turn-off effect. For example... Figure 1a As shown, towards MnO4 − When AA solution is added dropwise to the @Mn(Ⅱ)-CP system, the fluorescence intensity of the system gradually recovers and increases with the change in AA concentration. When the AA concentration is 6×10⁻⁶... −5 At M, the luminescence intensity of the system recovered to more than 50% of the original luminescence intensity of Mn(Ⅱ)-CP; when the concentration increased to 9×10 −5 At point M, the luminescence intensity of the system almost completely recovered; with further increase in the AA concentration, the fluorescence of the system continued to enhance, reaching 2 × 10⁻⁶. −4 At M, the luminescence intensity reached 1.5 times that of the original Mn(II)-CP; when the AA concentration increased to 3×10 −4 At concentration M, the luminescence intensity reached its peak, 1.8 times the original intensity. Further addition of AA did not change the luminescence intensity. Within the AA concentration range of 0-0.01 mM, MnO4... − The @Mn(Ⅱ)-CP system exhibits a good linear relationship between I0 / I and AA concentration, which can be verified using the Stern-Volmer equation: I0 / I = K sv Linear fitting was performed using [M] + 1, where I0 and I are the concentrations of MnO4 before and after the addition of AA, respectively. − @Mn(Ⅱ)-CP luminescence intensity, [M] is the molar concentration of AA, K sv This represents the slope of the line or the Stern-Volmer constant. For example... Figure 1b As shown, the fitted linear equation is I0 / I = −0.02145[AA] + 0.978, R0 2 =0.999, K sv The value is 2.145 × 10 4 M −1 According to 3σ / K sv The calculated LOD is 1.96 × 10⁻⁶. −6 M. In addition, such as Figure 1c As shown, MnO4 − @Mn(Ⅱ)-CP samples were recovered and regenerated after each AA detection by centrifugation, filtration, and multiple deionized water washing. After four cycles, Mn(Ⅱ)-CP could basically recover to its initial fluorescence intensity, and AA was effective against MnO4. − The fluorescence recovery ability of the @Mn(Ⅱ)-CP system remains basically unchanged.

[0006] The above MnO4 −The redox reaction mechanism between AA and UV-Vis can be fully confirmed through ultraviolet-visible (UV-Vis) absorption spectroscopy, macroscopic color changes in the solution, and Tyndall effect experiments, such as... Figure 2 As shown. AA titration of MnO4 − The UV-Vis absorption spectrum of the solution shows that with the addition of AA, MnO4 − The characteristic peaks of the UV-Vis absorption spectrum gradually weaken, indicating that AA and MnO4... − A redox reaction occurred. AA belongs to aliphatic compounds, contains an enediol structure, and has strong reducing properties, reacting with MnO4. − It can undergo a redox reaction, and the product is Mn. 2+ And dehydroascorbic acid. Figure 2 As shown in the illustration, with the addition of AA solution, MnO4... − The solution color disappeared and no Tyndall effect was observed, indicating that MnO4... − The reduction product is Mn 2+ Therefore, MnO4 − Before being completely reduced, AA can gradually eliminate MnO4. − The fluorescence turn-off effect of Mn(II)-CP is restored, bringing Mn(II)-CP to a fluorescence turn-on state; MnO4 − After complete reduction, with the continued addition of AA, AA exhibits a specific fluorescence enhancement effect on Mn(II)-CP, causing the fluorescence intensity of the system to exceed the initial fluorescence intensity of Mn(II)-CP, thus achieving a turn-on fluorescence enhancement. plus )state. Based on AA for MnO4 − The fluorescence recovery performance of the @Mn(Ⅱ)-CP system was studied, a ternary logic output rule was established, and a molecular logic gate with ternary (0, 1, 2) outputs was constructed, such as... Figure 3a As shown. This logic gate is a single-output, multi-input logic gate, where AA is the main signal input and MnO4 is the input. − To suppress the input, the output is affected by the suppression signal when the suppression input is active, and determined by the main signal when the suppression input is inactive. Therefore, the fluorescence emission intensity of Mn(Ⅱ)-CP is defined as the output signal of the logic gate, which can realize a ternary (0, 1, 2) output, such as... Figure 3b As shown. Figure 3b The diagram shows the molecular logic gates and their corresponding truth values ​​based on the normalized fluorescence emission intensity of Mn(II)-CP. I / I0 represents the normalized fluorescence emission intensity, I0 is the initial fluorescence intensity of Mn(II)-CP, and I is the system fluorescence intensity. The specific logic assignment rules are as follows: MnO4 is not added. −Let this be the input signal "0", then add MnO4. − The input signal is recorded as "1"; no AA is recorded as "0"; adding an appropriate amount of AA is recorded as "1"; adding excessive AA results in a fluorescence super-enhanced turn-on. plus The state is denoted as input signal "2"; based on the initial luminescence intensity of Mn(II)-CP, an intensity greater than 1 times the initial luminescence intensity of Mn(II)-CP is denoted as output signal "2", an intensity less than 0.2 times is denoted as output signal "0", and an intensity between the two is denoted as output signal "1". According to the above definition, when MnO4 is added... − Without the addition of AA, the fluorescence intensity of the system drops to less than 0.2 times the initial luminescence intensity of Mn(II)-CP, at which point the output signal is determined to be "0"; when AA is added, but without the addition of MnO4... − When Mn(II)-CP is added, the luminescence intensity is more than twice its initial intensity, and the output signal is determined to be "2"; when MnO4 is added... − When an appropriate amount of AA is added, the luminescence intensity of Mn(II)-CP is between 0.2 and 1 times the initial luminescence intensity, and the output signal is determined to be "1"; when MnO4 is added... − When AA is added in excess, the output signal of the system is more than twice the initial luminescence intensity of Mn(II)-CP, and the output signal is determined to be "2". By controlling the input combination state of the two substances, a stable, repeatable, and highly distinguishable ternary (0, 1, 2) logic operation output is achieved, which solves the technical bottleneck that traditional fluorescent logic gates cannot achieve ternary operations. Under the criterion of identifying three gradient states—initial fluorescence / recovery fluorescence, quenching fluorescence, and enhanced fluorescence—the system operates in a ternary (0, 1, 2) logic mode. The selected AA eliminates MnO4 through redox reactions. − The quenching effect of MnO4 − Once completely eliminated, AA can specifically enhance the fluorescence emission intensity of Mn(II)-CP without causing fluorescence signal disorder or state overlap, and can stably maintain fluorescence turn-off, normal turn-on, and super-enhanced turn-on. plus Three independent steady states ensure the accuracy and repeatability of ternary logic output.

[0007] In addition, AA for MnO4 − The fluorescence recovery performance of the @Mn(Ⅱ)-CP system allows for the construction of not only ternary (0, 1, 2) output logic gates, but also ternary (-1, 0, 1) output logic gates, thus enabling the mutual conversion between the two types of ternary logic gates. Figure 4a As shown. Therefore, MnO4 −As a suppression input; AA as the main signal input; the fluorescence enhancement efficiency of Mn(Ⅱ)-CP is defined as the output signal of the logic gate, which can realize a ternary (-1, 0, 1) output, such as Figure 4b As shown, the fluorescence enhancement efficiency is (I-I0) / I0, where I0 is the initial fluorescence intensity of Mn(II)-CP and I is the fluorescence intensity of the system. Figure 4b This paper presents molecular logic gates that achieve logical functions based on the fluorescence enhancement efficiency of Mn(II)-CP, along with their corresponding truth values. The specific logic assignment rules are as follows: MnO4 is not added. − Let this be the input signal "-1", then add MnO4. − The input signal is recorded as "1"; no AA is recorded as "-1"; adding an appropriate amount of AA is recorded as "0"; adding excess AA results in a fluorescence super-enhanced turn-on. plus The state is denoted as input signal "1"; based on the initial fluorescence intensity of Mn(Ⅱ)-CP, a fluorescence enhancement efficiency greater than 0 is denoted as output signal "1", a fluorescence enhancement efficiency less than -80% is denoted as output signal "-1", and a fluorescence enhancement efficiency between -80% and 0 is denoted as output signal "0". According to the above definitions, when MnO4 is not added... − Without the addition of AA, the fluorescence enhancement efficiency of Mn(II)-CP is 0, and the output signal is determined to be "0". When MnO4 is added... − Without the addition of AA, the fluorescence of Mn(II)-CP is significantly quenched, with a fluorescence enhancement efficiency below -80%, at which point the output signal is determined to be "-1". When AA is added, but without MnO4... − When Mn(II)-CP fluorescence intensity is higher than the initial value, fluorescence enhancement efficiency is greater than 0, and the output signal is determined to be "1"; when MnO4 is added... − With an appropriate amount of AA, the fluorescence enhancement efficiency of Mn(II)-CP is between -80% and 0, and the output signal is determined to be "0"; when MnO4 is added... − When there is excess AA, the fluorescence enhancement efficiency of Mn(Ⅱ)-CP is greater than 0, and the output signal is determined to be "1".

[0008] Compared with the prior art, the present invention has the following advantages: (1) This invention is the first to be based on coordination polymer on-off-on-on plus The fluorescent response system constructs a ternary logic gate, breaking through the limitation of traditional fluorescent logic gates that can only perform binary logic operations; (2) This invention realizes the (0, 1, 2) ternary logic output and the mutual conversion with the (-1, 0, 1) output mode. The mode can be switched according to the actual detection and operation needs, which has stronger functional expandability and wider application scenarios; (3) This invention relies on a Mn(II)-CP fluorescence response, which has high system stability and good repeatability. The input and output logic correspondence is clear. It does not require complex and precise equipment, is easy to operate and has low cost, which is conducive to its application in fields such as intelligent sensing, optoelectronic devices, logic operation chips and information encryption. Attached Figure Description

[0009] Figure 1a MnO4 was added dropwise to the AA solution. − Fluorescence response of @Mn(Ⅱ)-CP Figure 1b MnO4 − Stern–Volmer plot of fluorescence recovery of @Mn(Ⅱ)-CP Figure 1c MnO4 − Fluorescence intensity during @Mn(Ⅱ)-CP cycling Figure 2 AA titration of MnO4 − UV-Vis absorption spectra of the solution, inset: MnO4 before (left) and after (right) addition of AA. − Photo of the solution Figure 3a Normalized fluorescence intensity of Mn(II)-CP used for constructing logic gates under different input combinations Figure 3b MnO4 − The ternary (0, 1, 2) output logic gate constructed with input AA and its corresponding truth value. Figure 4a To assess the fluorescence enhancement efficiency of Mn(II)-CP used for constructing logic gates under different input combinations Figure 4b MnO4 − The ternary (-1, 0, 1) output logic gate constructed with input AA and its corresponding truth value Detailed Implementation

[0010] Example 1: Preparation of Mn(II) coordination polymer (Mn(II)-CP) sample and preparation of mother liquor Referring to the literature Dyes and Pigments, 2026, 246: 113390, the steps are briefly described as follows: 0.022 g (0.1 mmol) MnSO4·4H2O, 0.016 g (0.1 mmol) 4,4'-bipy and 0.012 g (0.05 mmol) H2 LDissolved in 15 mL of deionized water, the solution was sealed in a 20 mL PTFE-lined stainless steel reactor, heated to 130 °C and maintained for 48 h, then slowly cooled to room temperature to obtain yellow, blocky Mn(II)-CP crystals. The crystals were filtered, washed with deionized water and ethanol, dried at room temperature, ground, and then sealed for later use. This Mn(II)-CP exhibits stable fluorescence emission in aqueous solution, initially in a turn-on state. The prepared concentration was 1 × 10⁻⁶. −4 MnO4 − Aqueous solution, concentration 1×10 −4 M in AA aqueous solution, stored away from light and at low temperature.

[0011] Example 2 MnO4 − Fluorescence response and AA concentration gradient test of the Mn(II)-CP system Take 3 mg of dried Mn(II)-CP sample and disperse it in 3 mL of 1×10 −4 MnO4 − In an aqueous solution, the mixture was sonicated for 15 min to form a homogeneous suspension, which was then transferred to a 1 cm wide quartz cuvette as MnO4. − In the Mn(II)-CP test system, the fluorescence was significantly quenched, indicating a fluorescence turn-off state. AA stock solution was added dropwise to the above system. When the AA concentration was 6 × 10⁻⁶... −5 At M, the fluorescence intensity of the system recovered to more than 50% of the original fluorescence intensity of Mn(Ⅱ)-CP; when the AA concentration increased to 9×10 −5 At time M, the fluorescence of the system basically recovered to the initial level; when the AA concentration was 2×10 −4 At M, the fluorescence intensity reached 1.5 times the original intensity; when the AA concentration was 3×10 −4 At point M, the fluorescence intensity reaches its peak, 1.8 times the original intensity; further addition of AA stock solution does not change the fluorescence intensity. This system can achieve fluorescence on / off → fluorescence off → conventional on → super-enhanced on (turn-on) plus The gradient response of ) provides a foundation for the construction of ternary logic gates.

[0012] Example 3: Fluorescence linear fitting and detection limit determination The concentration of AA was controlled within the range of 0–0.01 mM, and MnO4 was tested sequentially at different AA concentrations. − Fluorescence intensity of the @Mn(Ⅱ)-CP system. The Stern-Volmer equation I0 / I=K was used. sv [M]+1 (I0 and I represent the fluorescence intensity of the system without AA and with AA, respectively; [M] is the molar concentration of AA; K...) svLinear fitting of the experimental data (where I is the slope of the line or the Stern-Volmer constant) yields the linear equation: I0 / I = −0.02145[AA] + 0.978, with a linear correlation coefficient R0. 2 =0.999; the Stern-Volmer constant K was obtained by fitting. sv =2.145×10 4 M −1 According to the limit of detection (LOD) formula 3σ / K sv The final calculated LOD of this system for AA is 1.96 × 10⁻⁶. −6 M. This system has a high sensitivity to AA.

[0013] Example 4: Mn(II)-CP Cyclic Regeneration Performance Test MnO4 after AA fluorescence detection − The Mn(II)-CP mixture was subjected to centrifugation and filtration to separate the solid sample. The solid sample was then washed multiple times with deionized water to regenerate the Mn(II)-CP sample. The regenerated Mn(II)-CP was then redispersed in MnO4. − A quenching system was constructed in aqueous solution, and the fluorescence detection, recovery, and regeneration procedures described above were repeated four times. After four cycles, the fluorescence intensity of the regenerated Mn(II)-CP was essentially the same as that of the initial sample, and the fluorescence intensity of MnO4 was... − The fluorescence quenching and fluorescence recovery effects of the system were not significantly different from those of AA, and the sample showed good cyclic stability and could be repeatedly used in the logic gate detection system.

[0014] Example 5 MnO4 − Characterization experiment of redox reaction with AA The testing instrument used was a UV-Vis spectrophotometer; the experimental reagents were directly prepared using the 1×10⁻⁶ reagents from Example 1. − 4 M MnO4 − Aqueous solution and 1×10 −4 MAA aqueous solution. Take an appropriate amount of MnO4. − An aqueous solution was added to a cuvette, and the initial UV-Vis absorption spectrum of the system was collected. Then, AA solution was added dropwise to the system, and after each drop was added and thoroughly mixed, the corresponding UV-Vis absorption spectrum was collected sequentially, observing the color change of the solution throughout the process. After the reaction was complete, the reaction system was irradiated with a laser pointer to detect the presence of the Tyndall effect.

[0015] Experimental Results and Analysis (1) UV-Vis spectral results: As AA solution was continuously added, MnO4 − The characteristic absorption peak intensity gradually decreases, proving that MnO4 is present in the system.− (2) Macroscopic color change: pure MnO4 is continuously consumed and undergoes redox reaction; − The aqueous solution is characteristically purplish-red. With the addition of AA, the purplish-red color of the solution gradually fades and eventually becomes colorless and transparent. (3) Tyndall effect detection: After irradiating the system with a laser pointer, no Tyndall effect was observed, indicating that no colloidal particles or solid precipitates were formed in the system. Based on the reaction rules, it can be known that the strong oxidizing MnO4 − Reduced to soluble Mn 2+ The reducing AA is oxidized to dehydroascorbic acid.

[0016] In summary, MnO4 − It can undergo a complete redox reaction with AA, and the reaction products are all soluble substances, providing a reliable chemical basis for the fluorescence gradient regulation and construction of ternary molecular logic gates in the system of this invention.

[0017] Example 6: Construction and Performance of Ternary (0, 1, 2) Molecular Logic Gates With MnO4 − To suppress the input signal, AA is used as the main input signal, and Mn(II)-CP fluorescence intensity is used as the output signal. Input and output assignment rules are set. Input rule: No MnO4 is added. − Record this as input 0, add MnO4 − Input 1 is recorded as input 0 if no AA is added, input 1 is recorded as input 1 if an appropriate amount of AA is added, and input 2 is recorded as input 2 if an excessive amount of AA is added (to achieve super-enhanced fluorescence). Output rules: Based on the initial fluorescence intensity of Mn(Ⅱ)-CP, output 0 is recorded as output 0 if the fluorescence intensity of the system is 0.2 times lower than the initial intensity of Mn(Ⅱ)-CP, output 1 is recorded as output 1 if the fluorescence intensity is between 0.2 and 1 times the initial intensity, and output 2 is recorded as output 2 if the fluorescence intensity is more than 1 times higher than the initial intensity.

[0018] Multiple control experimental groups were set up, and the combined states of the two input signals were adjusted respectively. The system output results were then tested. Group 1: Add MnO4 − Without the addition of AA, the fluorescence of the system is significantly quenched, the fluorescence intensity is 0.2 times lower than the initial value, and the logic output is 0. Group 2: No MnO4 added − The addition of AA resulted in a super-enhanced fluorescence in the system, with the intensity exceeding the initial value by 1 time, and the logic output was 2. Group 3: Add MnO4 − Adding an appropriate amount of AA will restore the fluorescence to 0.2 to 1 times its initial intensity, and the logic output will be 1. Group 4: Add MnO4 − When excess AA is added, the fluorescence intensity is more than twice the initial value, and the logic output is 2.

[0019] The experimental results of each group have high discrimination and good repeatability, and a stable ternary (0, 1, 2) logic operation has been successfully achieved, breaking through the limitations of traditional binary fluorescent logic gates.

[0020] Example 7: Construction of Ternary (-1, 0, 1) Molecular Logic Gates and Dual-Mode Conversion MnO4 − Using suppression input and AA as the main input, and Mn(II)-CP fluorescence enhancement efficiency as the output signal, the assignment rules are reset. Input rule: No MnO4 is added. − Record this as input -1, add MnO4 − Input 1 is recorded as input 1; input -1 is recorded as input 0 is recorded as input 0 is recorded as input 0 is recorded as input 1 is recorded as input 1 is recorded as input 0 is recorded as input 0 is recorded as input 1 is recorded as input 0 is recorded as input 0 is recorded as input 1 is recorded as input 1 is recorded as input 1 is recorded as input 0 ...0 is recorded as input 0 is recorded as input 0 is recorded as input 1 is recorded as input 1 is recorded as input 0 is recorded as input 0 is recorded as input 0 is recorded as input 1 is recorded as input 1 is recorded as input 0 is recorded

[0021] Multiple experimental groups were set up for testing: Group 1: No MnO4 added − Without the addition of AA, the fluorescence of the system remains unchanged, the enhancement efficiency is 0, and the logic output is 0. Group 2: Add MnO4 − Without the addition of AA, fluorescence is significantly quenched, enhancement efficiency is less than -80%, and the logic output is -1; Group 3: No MnO4 added − Adding AA enhances fluorescence, resulting in an enhancement efficiency greater than 0, and the logic output is 1. Group 4: Add MnO4 − Adding an appropriate amount of AA partially restores the fluorescence, enhances the efficiency to the range of -80% to 0, and results in a logic output of 0. Group 5: Add MnO4 − Adding excessive AA significantly enhances fluorescence, with an enhancement efficiency greater than 0, resulting in a logic output of 1.

[0022] This system can freely switch between two logic modes, ternary (0, 1, 2) and ternary (-1, 0, 1), by changing the assignment rules, thus expanding the application scenarios of fluorescent molecular logic gates.

Claims

1. A method for constructing and converting output modes of a fluorescence-responsive ternary logic gate based on Mn(II) coordination polymers, characterized in that, Includes the following steps: S1. Select Mn(II) coordination polymer (Mn(II)-CP) with stable fluorescence emission as the basic material for fluorescence response and construct an initial fluorescence turn-on system; S2. With MnO4 − To suppress the input signal, ascorbic acid (AA) is used as the main input signal; MnO4 is utilized. − Specific fluorescence quenching (turn-off) effect of Mn(II)-CP, AA and MnO4 − The redox reaction re-turns Mn(II)-CP fluorescence and AA provides specific fluorescence super-enhancement of Mn(II)-CP. plus This function constructs an on-off-on-on network with gradient response characteristics. plus Fluorescent response system; S3. Based on the on-off-on-on... plus A gradient fluorescence response system is established, and a first set of ternary assignment rules is constructed to create a ternary fluorescence logic gate with an output of (0, 1, 2). In the first set of ternary assignment rules, the input signal is defined as: without MnO4. − Add MnO4 to the input of 0. − Input 1 is the result of adding AA; input 0 is the result of not adding AA, input 1 is the result of adding an appropriate amount of AA, and input 2 is the result of adding excessive AA to form a state of super-enhanced fluorescence. The output signal is defined based on the initial fluorescence intensity of Mn(Ⅱ)-CP: output 0 is the result of fluorescence intensity being 0.2 times lower than the initial intensity, output 1 is the result of fluorescence intensity being between 0.2 and 1 times the initial intensity, and output 2 is the result of fluorescence intensity being in a super-enhanced state, i.e., more than 1 times the initial intensity. S4. Switch the output mode of the fluorescent logic gate, establish a second set of ternary assignment rules, construct a ternary fluorescent logic gate with an output of (-1, 0, 1), and realize the conversion between two different ternary output modes; in the second set of ternary assignment rules, the input signal is defined as: without MnO4. − Add MnO4 to the input -1 − Input 1 is the input for Mn(II)-CP. Input -1 is the input for Mn(II)-CP without AA, input 0 is the input for Mn(II)-CP with appropriate AA, and input 1 is the input for Mn(II)-CP with excessive AA to form a super-enhanced fluorescence state. The output signal is defined based on the fluorescence enhancement efficiency corresponding to the initial fluorescence intensity of Mn(II)-CP: output -1 is the fluorescence enhancement efficiency less than -80%, output 0 is the fluorescence enhancement efficiency between -80% and 0, and output 1 is the fluorescence enhancement efficiency greater than 0, i.e., the fluorescence intensity is in a super-enhanced state.

2. The method according to claim 1, characterized in that, In step S2, AA eliminates MnO4 through a redox reaction. − Fluorescence quenching effect on Mn(II)-CP; As the concentration gradient of AA increases, the fluorescence of the system gradually recovers from the quenched state, and MnO4... − After complete consumption, AA further enhances the fluorescence of the system, and the fluorescence response of the system exhibits a gradient change characteristic.

3. The method according to claim 2, characterized in that, AA to MnO4 − The fluorescence gradient response of the @Mn(Ⅱ)-CP system satisfies the following parameters: AA concentration is 6×10 −5 At M, the fluorescence intensity of the system recovered to more than 50% of the original luminescence intensity of Mn(II)-CP; the AA concentration was 9×10 −5 At time M, the fluorescence intensity of the system was almost completely recovered; the AA concentration was 2×10⁻⁶. −4 At time M, the fluorescence intensity of the system reached 1.5 times the original intensity; the AA concentration was 3 × 10⁻⁶. −4 At point M, the fluorescence intensity of the system reaches its peak, which is 1.8 times the original intensity. Further increasing the AA concentration will not change the fluorescence intensity of the system.

4. The method according to claim 2, characterized in that, Within the AA concentration range of 0–0.01 mM, MnO4 − The I0 / I ratio of the @Mn(Ⅱ)-CP system exhibits a good linear relationship with the AA concentration, as confirmed by the Stern-Volmer equation: I0 / I = K sv Linear fitting with [M] + 1 yields the linear equation I0 / I = −0.02145[AA] + 0.978, with a fitting coefficient R0. 2 =0.999, Stern−Volmer constant K sv =2.145×10 4 M −1 Through 3σ / K sv The calculated limit of detection (LOD) for AA was 1.96 × 10⁻⁶. −6 M.

5. The method according to claim 1, characterized in that, The Mn(II)-CP exhibits cyclic regeneration capabilities. After a single fluorescence response test, it can regenerate MnO4. − The Mn(II)-CP system can be regenerated by centrifugation, filtration, and multiple washing with deionized water. After four cycles of testing, Mn(II)-CP can be restored to its initial fluorescence intensity, and the fluorescence recovery and enhancement performance of AA on the system remains stable.

6. The method according to claim 1, characterized in that, The appropriate amount of AA is capable of counteracting MnO4. − The amount of AA used to achieve fluorescence quenching effect and stabilize the fluorescence intensity of the system within the range of 0.2 to 1 times the initial intensity of Mn(II)-CP; the excess AA is the amount used to produce a fluorescence super-enhancement effect in the system, with the fluorescence intensity being more than 1 times higher than the initial intensity of Mn(II)-CP.

7. The method according to claim 1, characterized in that, The Mn(II)-CP, MnO4 − The response system composed of AA can stably maintain fluorescence turn-off, conventional turn-on, and super-enhanced turn-on. plus Three independent steady states ensure the accuracy and repeatability of ternary logic output.

8. The method according to claim 1, characterized in that, The Mn(II)-CP was synthesized by a hydrothermal method. Specifically, 0.1 mmol MnSO4·4H2O, 0.1 mmol 4,4'-bipyridine, and 0.05 mmol 4,4'-azobis(2-hydroxybenzoic acid) were dissolved in 15 mL of deionized water and sealed in a 20 mL polytetrafluoroethylene-lined reactor. The mixture was reacted at a constant temperature of 130 °C for 48 h, and then slowly cooled to room temperature to obtain yellow blocky crystals, which were the Mn(II)-CP. The fluorescence test system was prepared by dispersing the Mn(II)-CP powder in the test solution, sonicating it to form a uniform suspension, adding the corresponding response reagent, and collecting the fluorescence spectrum to complete the gradient fluorescence response test.

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