Self‐Assembly of Anionic Porphyrins and Alkaline or Alkaline Earth Metal Ions Mediated by Cucurbit[7,8]uril

Nanoscaled coordination polymers based on biologically prevalent ions have potential applications in drug delivery and biomedical imaging. Herein, coordination polymer nanoparticles of anionic porphyrins, including meso‐tetra(4‐carboxyphenyl)‐porphyrin (H₂TCPP^4?) and meso‐tetra(4‐sulfonatophenyl)‐porphyrin (H₂TPPS^4?), and alkaline or alkaline earth metal cations, such as K⁺ and Ca²⁺, were constructed in aqueous solution in the presence of cucurbit[7]uril (CB7) or cucurbit[8]uril (CB8). UV/Vis absorption and fluorescence spectroscopy, dynamic light scattering (DLS), scanning electron spectroscopy (SEM), and atomic force microscopy (AFM) were applied to explore the assembly and particle formation of porphyrin anions and metal cations mediated by CBn. The particle size depends on the kinds of CBn and metal cations and their concentrations. The uptake of H₂TPPS^4? particles by tumor cells (A549 cells) was found to be more efficient than H₂TPPS^4? at 37 °C, showing the application potential of such assembled particles in biology and medicine.     

Supramolecular Formation of Li+@PCBM Fullerene with Sulfonated Porphyrins and Long‐Lived Charge Separation

Lithium‐ion‐encapsulated [6,6]‐phenyl‐C₆₁‐butyric acid methyl ester fullerene (Li⁺@PCBM) was utilized to construct supramolecules with sulfonated meso‐tetraphenylporphyrins (MTPPS^4?; M=Zn, H₂) in polar benzonitrile. The association constants were determined to be 1.8×10⁵ M ^?1 for ZnTPPS^4?/Li⁺@PCBM and 6.2×10⁴ M ^?1 for H₂TPPS^4?/Li⁺@PCBM. From the electrochemical analyses, the energies of the charge‐separated (CS) states were estimated to be 0.69 eV for ZnTPPS^4?/Li⁺@PCBM and 1.00 eV for H₂TPPS^4?/Li⁺@PCBM. Upon photoexcitation of the porphyrin moieties of MTPPS^4?/Li⁺@PCBM, photoinduced electron transfer occurred to produce the CS states. The lifetimes of the CS states were 560 μs for ZnTPPS^4?/Li⁺@PCBM and 450 μs for H₂TPPS^4?/Li⁺@PCBM. The spin states of the CS states were determined to be triplet by electron paramagnetic resonance spectroscopy measurements at 4 K. The reorganization energies (λ) and electronic coupling term (V) for back electron transfer (BET) were determined from the temperature dependence of k_BET to be λ=0.36 eV and V=8.5×10^?3 cm^?1 for ZnTPPS^4?/Li⁺@PCBM and λ=0.62 eV and V=7.9×10^?3 cm^?1 for H₂TPPS^4?/Li⁺@PCBM based on the Marcus theory of nonadiabatic electron transfer. Such small V values are the result of a small orbital interaction between the MTPPS^4? and Li⁺@PCBM moieties. These small V values and spin‐forbidden charge recombination afford a long‐lived CS state.     

Carbonized Hemoglobin Nanofibers for Enhanced H2O2 Detection

Electrospun hemoglobin (Hb) microbelts were used as a novel precursor to produce a new class of carbon nanofibers (Hb‐CNFs) containing Fe species (Fe₂O₃ and/or Fe‐N₄ moiety). The Hb‐CNFs modified glassy carbon electrode (Hb‐CNFs/GCE) exhibits significant oxidation/reduction towards H₂O₂. The observed H₂O₂ oxidation/reduction starting at ca. +0.26 V and +0.15 V (vs. Ag/AgCl) are significantly lower than the values observed at other CNFs modified GCE. The Hb‐CNFs/GCE was also applied to the amperometric detection of H₂O₂ and the results showed fast response, high sensitivity, excellent reproducibility, good selectivity, and wide dynamic range with good limit of detection.     

Electrochemical Studies of a New Iron Porphyrin Entrapped in a Propylpyridiniumsilsesquioxane Polymer Immobilized on a SiO2/Al2O3 Surface

In this work, a new porphyrin, the 5,10,15,20‐tetrakis‐(2,6‐difluoro‐3‐sulfonatophenyl) porphyrinato iron(III) chloride (denoted as FeTsP) was immobilized on SiO₂/Al₂O₃ (SiAl) coated with n‐propylpyridiniumsilsesquioxane polymer (SiPy⁺Cl^?). The FeTsP was adsorbed on SiAl/SiPyCl by an ion exchange reaction, obtaining a modified solid, SiAl/SiPy/FeTsP, where the porphyrin complex was strongly adhered. Cyclic voltammograms of the SiAl/SiPy/FeTsP carbon paste electrode showed an irreversible response, with an oxidation peak at E_pa=0.40 V and nondefined reduction peak at E_pc=0.15 V (vs. SCE). These peaks were not observed for the nonmetallated porphyrin, indicating that they probably correspond to the Fe(III)/Fe(II) process. Studies made in solutions having different pH, (between pH 2 and 9) using the modified electrode showed that the peak potentials and the current density were not affect by pH changes, indicating that the iron porphyrin is very stable and strongly entrapped in the matrix. The modified electrode presented the property to electrocatalyze the eletrooxidation of hydrazine at 0.41 V (vs. SCE), at pH 7. The potentiality of the SiAl/SiPy/FeTsP electrode as a sensor for hydrazine was evaluated by the using the chronoamperometric technique. A linear response was obtained in the concentration range between 5×10^?5 and 6×10^?4 mol L^?1 of hydrazine.     

Evaluation of antioxidative capacity via measurement of the damage of DNA using an electrochemical biosensor and an ionic liquid solvent

We report on the electrodeposition of palladium nanomaterials in choline chloride–based ionic liquid ethaline. A glassy carbon electrode (GCE) was modified with cobalt nanoparticles (acting as sacrificial templates) and a GCE modified with palladium nanoparticles (PdNPs) were fabricated and used to study the electrocatalytic oxidation of hydrazine (N₂H₄). Scanning electron microscopy revealed that the PdNP modified GCE has a uniform morphology. Zero current potentiometry was used for in-situ probing the changes in interfacial potential of the oxidation of hydrazine. An amperometric study showed that the PdNP modified GCE possesses excellent electrocatalytic activity towards N₂H₄. The modified electrode displays a fast response (<2 s), high sensitivity (74.9 μA m(mol L^?1)^?1?cm^?2) and broad linearity in the range from 0.1 to 800 μmol L^?1 with a detection limit of 0.03 μmol L^?1 (S/N?=?3).

Spectroscopic studies of nanostructures of negatively charged free base porphyrin and positively charged tin porphyrins

Spectroscopic studies were carried out on the homoaggregates of negatively charged free base meso-tetraphenylsulfonated porphyrin ([H₂TPPS₄]⁴⁻) and heteroaggregates of a mixture of protonated ([H₄TPPS₄]²⁻) and tin meso-tetra (N-methyl-4-pyridyl) porphyrin ([SnTMPyP]⁴⁺). The spectroscopic studies were done to determine the optimal conditions required for the fabrication of porphyrin nanorods by ionic self assembly of two oppositely charged porphyrins. In addition, the various spectral changes of [H₄TPPS₄]²⁻ with concurrent change in pH and concentration are also investigated. In acid media at pH <3, and at concentrations >1 × 10⁻⁵ M, [H₄TPPS₄]²⁻ molecules form J aggregates. A mixture of [H₄TPPS₄]²⁻ and [SnTMPyP]⁴⁺ forms heteroaggregates of the J type in acid media. At pH’s 2 to 3, the optimum ratio for the formation of J aggregates is 3:1 and for pH 1, the optimum ratio is 2:1. Transmission electron microscope images of the nanostructures formed show that they are of cylindrical shape.     

Electrochemical Behavior and Determination of L‐Tyrosine at Single‐walled Carbon Nanotubes Modified Glassy Carbon Electrode

Based on single‐walled carbon nanotubes (SWCNTs) modified glassy carbon electrode (GCE/SWCNTs), a novel method was presented for the determination of L ‐tyrosine. The GCE/SWCNTs exhibited remarkable catalytic and enhanced effects on the oxidation of L ‐tyrosine. In 0.10 mol/L citric acid‐sodium citrate buffer solution, the oxidation potential of L ‐tyrosine shifted negatively from +1.23 V at bare GCE to +0.76 V at GCE/SWCNTs. Under the optimized experimental conditions, the linear range of the modified electrode to the concentration of L ‐tyrosine was 5.0×10^?6–2.0×10^?5 mol/L (R₁=0.9952) and 2.7×10^?5–2.6×10^?4 mol/L (R₂=0.9998) with a detection limit of 9.3×10^?8 mol/L. The kinetic parameters such as α (charge transfer coefficient) and D (diffusion coefficient) were evaluated to be 0.66, 9.82×10^?5 cm² s^?1, respectively. And the electrochemical mechanism of L ‐tyrosine was also discussed.     

Behavior of Palladium Nanoparticles in the Absence or Presence of Cobalt Tetraaminophthalocyanine for the Electrooxidation of Hydrazine

We report on the electrodeposition of palladium nanoparticles (PdNPs) on a glassy carbon electrode (GCE) and onto a poly‐CoTAPc‐GCE (CoTAPc=cobalt tetraamino phthalocyanine) surface. The electrodes are denoted as PdNPs‐GCE and PdNPs/poly‐CoTAPc‐GCE, respectively. PdNPs/poly‐CoTAPc‐GCE showed the best activity for the oxidation of hydrazine at the lowest potential of ?0.28 V and with the highest currents. The results were further supported by electrochemical impedance spectroscopy (EIS) which showed that there was less resistance to charge transfer for PdNPs/poly‐CoTAPc‐GCE compared to PdNPs‐GCE. The catalytic rate constant for hydrazine oxidation was 6.12×10⁸ cm³ mol^?1 s^?1 using PdNPs/poly‐CoTAPc‐GCE.     

The Marriage of Peripherally Metallated and Directly Linked Porphyrins: Bromidobis(phosphine)platinum(II) as a Cation‐Stabilizing Substituent on Directly Linked and Fused Triply Linked Diporphyrins

A meso‐bromidoplatiniobis(triphenylphosphine) η¹‐organometallic porphyrin monomer was prepared by the oxidative addition of meso‐bromoZnDPP (DPP=dianion of 5,15‐diphenylporphyrin) to a platinum(0) species. The meso–meso directly linked dimeric porphyrin ( 5 ) was prepared from this monomer by silver(I)‐promoted oxidative coupling and planarized to give a triply linked dizinc(II) porphyrin dimer ( 8 ). Acidic demetallation of 8 afforded the bis(free base) 9 . Dimer 5 was demetallated then remetallated with nickel(II) to give the dinickel(II) analogue 10 , the X‐ray crystal structure of which showed a twisted molecule with ruffled, orthogonal NiDPP rings, terminated by square‐planar trans‐[Pt(PPh₃)₂Br] units. New compounds were fully characterized spectroscopically, and the fused diporphyrin exhibited a broad, low‐energy, near‐IR electronic absorption band near 1100 nm. Electrochemical measurements of this series indicate that the organometallic fragment is a strong electron donor towards the porphyrin ring. The triply linked organometallic diporphyrin has a substantially lowered first one‐electron oxidation potential (?0.35 V versus the ferrocene/ferrocenium couple (Fc/Fc⁺)) and a narrow HOMO–LUMO gap of 0.96 V. Solutions prepared for NMR spectroscopy slowly decompose with degradation of the signals, which is attributed to partial oxidation to the cation radical. This paramagnetic species can be reduced in situ by hydrazine to restore the NMR spectrum to its former appearance. The combined influence of the two [Pt(PPh₃)₂Br] electron‐donating substituents is sufficient to make dimer 5 too aerobically unstable to allow further elaboration.     

Large Porphyrin Squares from the Self‐Assembly of meso‐Triazole‐Appended L‐Shaped meso–meso‐Linked ZnII–Triporphyrins: Synthesis and Efficient Energy Transfer

meso‐Triazolyl‐appended Zn^II–porphyrins were readily prepared by Cu^I‐catalyzed 1,3‐dipolar cycloaddition of benzyl azide to meso‐ethynylated Zn^II–porphyrin (click chemistry). In noncoordinating CHCl₃ solvent, spontaneous assembly occurred to form tetrameric array ( 3 )₂ from meso–meso‐linked diporphyrins 3 , and dodecameric porphyrin squares ( 4 )₄ and ( 5 )₄ from the L ‐shaped meso–meso‐linked triporphyrins 4 and 5 . The structures of these assemblies were examined by ¹H NMR spectra, absorption spectra, and their gel permeation chromatography (GPC) retention time. Furthermore, the structures of the dodecameric porphyrin squares ( 4 )₄ and ( 5 )₄ were probed by small‐ and wide‐angle X‐ray scattering (SAXS/WAXS) measurements in solution using a synchrotron source. Excitation‐energy migration processes in these assemblies were also investigated in detail by using both steady‐state and time‐resolved spectroscopic methods, which revealed efficient excited‐energy transfer (EET) between the meso–meso‐linked Zn^II–porphyrin units that occurred with time constants of 1.5 ps^?1 for ( 3 )₂ and 8.8 ps^?1 for ( 5 )₄.     

Imine Gels Based on Ferrocene and Porphyrin and Their Electrocatalytic Property

A series of porphyrin‐based imine gels have been synthesized via dynamic covalent gelation between 5,10,15,20‐tetra(4‐aminophenyl)‐21H,23H‐porphyrin (H₂TAPP) derivatives and various aldehyde compounds. The porphyrin‐ferrocene imine gels based on MTAPP (M=H₂, Ni²⁺, Co²⁺, Pd²⁺ and Zn²⁺) and ferrocene‐1,1′‐dicarbaldehyde (NA) display efficient HER, OER and ORR activities in alkaline media. Among the gels, CoTAPP‐NA shows an HER current density of 10 mA cm^?2 at low overpotential of 470 mV and small Tafel slope of 110 mV decade^?1 in alkaline media. CoTAPP‐NA also exhibits OER catalytic activity with low overpotential (416 mV for 10 mA cm^?2). CoTAPP‐NA shows ability in overall water splitting in alkaline media. In addition, CoTAPP‐NA exhibits onset potential (E_p) of 0.95 V and half‐wave potential (E_1/2) of 0.84 V in 1.0 mol L^?1 KOH solution for oxygen reduction. Moreover, the gel catalyst shows good stability.     

Metallkomplexe mit Tetrapyrrol-Liganden. 68. Synthese wasserlöslicher Osmium-Porphyrin-Komplexe

Metal Complexes with Tetrapyrrole Ligands. 68. Synthesis of Water-Soluble Osmium Porphyrin Complexes The synthesis of osmium tetraphenylporphyrinates with functional groups in the para-position of the phenyl rings is described. By sulfonation of the corresponding para-unsubstituted complex the carbonylosmium(II)-complex [OsCO(TPPS₄)H₂O]^4? or the dioxoosmium(VI)-complex [OsO₂(TPPS₄)]^4? [(TPPS₄)^6?: hexa-anion of tetrakis(4-sulfonatophenyl)porphyrin] is obtained. The osmochrome complex [Os(TPPS₄)(1-Meim)₂]^4?, which changes to the osmichrome complex [Os(TPPS₄)(1-Meim)₂]^3? in the presence of air, is formed from the dioxo-compound by reduction. These anions are deposited as water-soluble sodium- or as water-insoluble tetraphenylarsonium salts. The novel osmochrome complex Os(TMeCPP)(1-Meim)₂ (TMeCPP)^2?: [dianion of tetrakis(4-methoxycarbonylphenyl)porphyrin] is transformed by alcaline saponification and precipitation with hydrochloric acid to the corresponding alcali-soluble osmochrome tetracarbonic acid Os(TH₄CPP)(1-Meim)₂. UV/Vis-, ¹H-NMR-spectra and electrophoreses provide insight into the behaviour of the osmiumporphyrinate anions in water.     

meso–meso‐Linked Diarylamine‐Fused Porphyrin Dimers

A meso–meso‐linked diphenylamine‐fused porphyrin dimer and its methoxy‐substituted analogue were synthesized from a meso–meso‐linked porphyrin dimer by a reaction sequence involving Ir‐catalyzed β‐selective borylation, iodination, meso‐chlorination, and S_NAr reactions with diarylamines followed by electron‐transfer‐mediated intramolecular double C?H/C?I coupling. While these dimers commonly display characteristic split Soret bands and small oxidation potentials, they produced different products upon oxidation with tris(4‐bromophenyl)aminium hexachloroantimonate. Namely, the diphenylamine‐fused porphyrin dimer was converted into a dicationic closed‐shell quinonoidal dimer, while the methoxy‐substituted dimer gave a meso–meso, β‐β doubly linked porphyrin dimer.     

Adsorptive Stripping Voltammetric Detection of Single‐Stranded DNA at Electrochemically Modified Glassy Carbon Electrode

Electrochemically modified glassy carbon electrode (GCE) was used to study the electrochemical oxidation and detection of denatured single‐stranded (ss) DNA by means of adsorptive stripping voltammetry. The modification of GCE, by electrochemical oxidation at +1.75 V (vs.SCE) for 10 min and cyclic sweep between +0.3 V and ?1.3 V for 20 cycles in pH 5.0 phosphate buffer, results in 100‐fold improvement in sensitivity for ssDNA detection. We speculated that the modified GCE has a high affinity to single‐stranded DNA through hydrogen bond (specific static adsorption). Single‐stranded DNA can accumulate at the GCE surface at open circuit and produce a well‐defined oxidation peak corresponding to the guanine residues at about +0.80 V in pH 5.0 phosphate buffer, while the native DNA gives no signal under the same condition. The peak currents are proportional to the ssDNA concentration in the range of 0–18.0 μg mL^?1. The detection limit of denatured ssDNA is ca. 0.2 μg mL^?1 when the accumulation time is 8 min at open circuit. The accumulation mechanism of ssDNA on the modified GCE was discussed.     

Effect of long alkyl chains of aniline donor on the photovoltaic performance of D‐π‐A zinc porphyrin for dye‐sensitized solar cells

Three novel dyes of JJ1 , JJ2 , and JJ6 featured zinc porphyrin as a basic core structure; N, N‐alkyl‐4‐(prop‐1‐yn‐1‐yl)aniline as an electron donor linked to meso‐10‐position; 4‐(prop‐1‐yn‐1‐yl)benzoic acid as an electron acceptor linked to meso‐20‐position; and 2,6‐bis(dodecyloxy)phenyl or 2,6‐bis(octyloxy)phenyl respectively linked to meso‐5 and meso‐15‐positions of zinc porphyrin have been synthesized and used for dye‐sensitized solar cells. Porphyrin JJ6 featured the shortest alkyl group (─C₄H₉) on the donor, whereas JJ2 contained the longest alkyl groups (─C₁₂H₂₅), and JJ1 has a medium length of octyl groups. With these new porphyrin sensitizers, we observed that JJ6 has 7.55% power conversion efficiency under simulated one‐sun illumination (AM 1.5 G, 100 mW/cm²) with J_SC = 18.64 mA/cm², V_OC = 0.66 V, and fill factor (FF) = 0.61, which was higher than the other two; JJ1 (7.35%) with J_SC = 18.83 mA/cm², V_OC = 0.68 V, and FF = 0.60; and JJ2 (6.33%) with J_SC = 15.69 mA/cm², V_OC = 0.62 V, and FF = 0.65. The power conversion efficiency of JJ6 and JJ1 were higher than JJ2 , demonstrating that the lengthy alkyl groups on the aniline cause a decrease in efficiency of the devices.     

Determination of Xenoestrogenic Compounds Using a Nanostructured Biosensing Device

A ternary composite material based on Prussian blue, single‐walled carbon nanotubes and 1‐butyl‐3‐methylimidazolium hexafluorophosphate was prepared and tested for electrochemical detection of H₂O₂. The sensor allows amperometric detection of H₂O₂ at ?0.05 V, with a sensitivity of 137 mA M^?1?cm^?2. The nanocomposite provides a favorable microenvironment for immobilization of horseradish peroxidase (HRP). Determination of xenoestrogenic compounds was performed by enzymatic oxidation at the surface of modified screen printed biosensor in the presence of H₂O₂. The developed electrochemical biosensors exhibited high sensitivity, low detection limits, good operational and storage stability, for detection of 4‐t‐butylphenol, 4‐t‐octylphenol, 4‐n‐nonylphenol and 4‐n‐nonylphenol ethoxylate.     

Determination of 1‐Naphthol with Denatured DNA–Modified Pretreated Glassy Carbon Electrode

Abstract

A highly sensitive electrochemical biosensor for the detection of trace amount of 1‐naphthol was designed. Acid‐denatured DNA were immobilized onto the pretreated glassy carbon electrode (GCE(ox)) surface. Two well‐defined oxidation peaks were observed on the denatured DNA‐modified GCE(ox) at about +0.80 V and +1.10 V (vs. Ag/AgCl) in 0.10‐M acetate buffer (pH 5.0). The peak current of the guanine residue decreased with increasing concentration of 1‐naphthol. The optimum experimental conditions for the detection of 1‐naphthol were explored, and the calibration was linear for 1‐naphthol in the range of 1.0×10^?8?1.1×10^?6 M, with a correlation coefficient of 0.998. The limit of detection (LOD) was 5.0×10^?9 M (S/N=3).     

Electrode Modified with Langmuir–Blodgett (LB) Film of Calixarenes for Preconcentration and Stripping Analysis of Hg(II)

A new type of current sensor, Langmuir–Blodgett (LB) film of calixarene on the surface of glassy carbon electrode (GCE) was prepared for determination of mercury by anodic stripping voltammetry (ASV). An anodic stripping peak was obtained at 0.15 V (vs. SCE) by scanning the potential from ?0.6 to +0.6 V. Compared with a bare GCE, the LB film coated electrode greatly improves the sensitivity of measuring mercury ion. The fabricated electrode in a 0.1 M H₂SO₄+0.01 M HCl solution shows a linear voltammetric response in the range of 0.07–40 μg L^?1 and detection limit of 0.04 μg L^?1 (ca. 2×10^?10 M). The high sensitivity, selectivity, and stability of this LB film modified electrode demonstrates its practical application for a simple, rapid and economical determination of Hg²⁺ in a water sample.     

Sensitive Determination of Terbutaline Using a Platform Based on Nanoparticles of Europium Oxide and Carbon Nanotubes

This study presents a sensitive voltammetric determination of terbutaline (TER) on a platform based on carbon nanotubes (CNTs) and europium oxide nanoparticles (Eu₂O₃NPs) coated glassy carbon electrodes (GCEs). An ultrasonic bath was performed for the preparation of composite material. The material was characterized by energy dispersive X‐ray spectroscopy (EDX), X‐ray diffraction method (XRD) and scanning electron microscopy (SEM). The Eu₂O₃NPs/CNTs/GCE system was assessed for the oxidation of terbutaline (TER). A broad oxidation peak was appeared at 0.71 V using a bare GCE. However, the voltammetry of TER has been improved at a GCE coated with CNTs and a well‐defined anodic peak exhibited at 0.61 V. Furthermore, the nanoparticles of Eu₂O₃ and CNTs coated GCE has greatly improved the electrochemical behaviour of TER and a sharp peak was appeared at 0.59 V. Cyclic voltammetry at Eu₂O₃NPs/CNTs/GCE also reveals a high catalytic effect for the oxidation of TER with an oxidation peak that is distinctly enhanced compared to GCE and CNTs/GCE. Eu₂O₃ nanoparticles were utilized to enhance the surface area of GCE and then improve the sensitivity of the procedure. The response of TER was linear over a concentration range of 2.0×10^?8 M ?9.5×10^?6 M with an LOD of 3.7×10^?9 M. Square wave voltammetric analysis of tablets by Eu₂O₃NPs/CNTs/GCE yielded a recovery of 99.2 % with an RSD% of 3.2. The modified electrode (EuO₂NPs/CNTs/GCE) provides accuracy and precision to the analysis of samples.     

In situ Electrochemical Synthesis of a Composite Film Containing Nickel Hexacyanoferrate and Bentonite Clay for the Sensitive Determination of Acetaminophen and Dopamine

A composite film of nickel hexacyanoferrate (NiHCF) and bentonite (Bt) clay (abbreviated as NiHCF?Bt) is synthesized by an in situ electrochemical method. For this synthesis, nickel ions are immobilized on Bt clay by an ion‐exchange process, equilibrating Bt clay with nickel nitrate. On a glassy carbon electrode (GCE), the nickel ion‐exchanged Bt clay (Ni²⁺?Bt) is coated to get the modified electrode which is represented as GCE/Ni²⁺?Bt. The NiHCF?Bt composite film is prepared on the GCE surface using the GCE/Ni²⁺?Bt and scanning the electrode potentials between ?0.10 to 1.00 V continuously in an aqueous solution containing potassium hexacyanoferrate and potassium chloride. This NiHCF?Bt modified GCE (GCE/NiHCF?Bt) exhibits redox peaks due to the oxidation and reduction of the central metal ion, Fe²⁺. The electro‐generated Fe³⁺ present in the GCE/NiHCF?Bt, electrocatalytically oxidizes a range of drugs like acetaminophen (AC), dopamine (DA), and tyrosine (TY) at decreased overpotentials with high current. This property is advantageously used for the precise quantification of AC, DA, and TY. Sensitivity, limit of detection, and linear calibration range for the determination of AC are found to be 0.20 μA μM^?1 cm^?2, 1.5 μM, and 25.0–1000.0 μM, respectively. Further, the amount of AC present in pharmaceutical products is satisfactorily quantified which demonstrated the use of the NiHCF?Bt composite film in electroanalysis.