Low Detection Limit Research Articles

Fluorescence/colorimetric dual-signal sensor based on carbon dots and gold nanoparticles for visual quantification of Cr3.

A convenient and sensitive dual-signal visualization method is constructed for detection of trivalent chromium ions (Cr3+) based on fluorescent carbon dots (CDs) and glutathione-modified gold nanoparticles (GSH-Au NPs). The fluorescence of CDs can be quenched by GSH-Au NPs due to the inner filter effect. Cr3+ induces aggregation of GSH-Au NPs because of the coordination with GSH on the surface of Au NPs, leading to the red shift of surface plasmon resonance absorption of Au NPs that provides a "turn-on" fluorescence and colorimetric assay for Cr3+. The fluorescence/colorimetric dual signal detection shows high sensitivity for Cr3+ with wide detection linear ranges (0.5-70μM for fluorescence detection and 2-50μM for colorimetric detection) and low detection limits (0.31μM for fluorescence detection and 0.30μM for colorimetric detection). Besides, the method has high selectivity for Cr3+ and can be used for detection of Cr3+ in lake water and tap water samples, showing great potential for visual detection of environmental Cr3+.

Aggregation-induced electrochemiluminescence of an indium-based metal–organic framework and resonance energy transfer strategy for the sensitive detection of β2-microglobulin

This study aimed to construct a novel aggregation-induced electrochemiluminescence (AIECL) system with an indium-based metal–organic framework (In-MOF) as a new luminophore and K2S2O8 as a co-reactant. In the constructed electrochemiluminescence (ECL) system, In-MOF served not only as a novel luminophore but also as a co-reaction accelerator. The In-MOF produced strong cathodic ECL emission over the wavelength range of 425–600 nm. The aggregation-caused quenching effect was overcome by altering the π-π stacking structure of 9,10-di(p-carboxyphenyl)anthracene (DPA) aggregates through coordination with metal ions. The In-MOF exhibited efficient ECL performance and better stability than the DPA ligand. Then, a novel quenched sensor based on the quenching effect of CeO2@PDA on the In-MOF ECL emission was fabricated for detecting β2-microglobulin (β2M). The immunosensor demonstrated an excellent linear relationship with a wide linear range (10 fg/mL – 200 ng/mL) and a low detection limit (2.9 fg/mL, S/N = 3) under optimized experimental conditions. The proposed biosensor had high sensitivity, reasonable specificity, high stability, and reproducibility, thus positively affecting the clinical application of sensing analysis.

A Mild Synthesis of 0D Mn2+‐Doped Cs3CdBr5 Metal Halide for White Light‐Emitting Diodes and X‐Ray Imaging

AbstractAll‐inorganic Cd‐based metal halide is widely studied and applied in the field of optoelectronics due to its superior stability, diverse phase structure, and unique photoelectric properties. However, all‐inorganic 0D Cd‐based metal halide is not widely studied due to their extreme synthesis conditions. In this paper, a simple mild solution method is devised to successfully synthesize 0D Cs3CdBr5 by manipulating the crystal growth kinetics. Simultaneously, the influence of the doping element Mn on the transition matrix and the optical properties are investigated. By doping with an appropriate concentration of Mn2+, a green emission (520 nm) with photoluminescence quantum yield (PLQY) as high as 97.39% is obtained. Benefiting from near‐unity PLQY and the excellent optical properties, the white emitting light‐emitting diodes (WLEDs) with Cs3CdBr5:20%Mn as green phosphor exhibit warm white light emission with color rendering index (CRI) of 91 and correlated color temperature (CCT) of 4108 K. In addition, Cs3CdBr5:20%Mn also demonstrates excellent X‐ray scintillation properties with a low detection limit of 32.83 nGyair·s−1. The results show that Cs3CdBr5:Mn is not only a promising candidate for solid‐state lighting but also a promising candidate for low‐dose high‐resolution X‐ray imaging.

MXene/MWCNTs-based capacitive pressure sensors combine high sensitivity and wide detection range for human health and motion monitoring

Wearable pressure sensors with exceptional performance are playing a crucial role in various fields such as electronic skin, human motion monitoring, medical diagnosis, and human-computer interaction. However, achieving both high sensitivity and a wide sensing range with simple fabrication and low cost has proven to be a significant challenge for sensors. In this study, a simple capacitive pressure sensor is proposed that multi-walled carbon nanotubes (MWCNTs) are introduced into MXene (Ti3C2TX) as a ‘bridge’. Then the electrode which has excellent conductivity is obtained by filtration of MXene solution and MXene/MWCNTs solution at intervals. Additionally, green and degradable cellulose paper is used as the dielectric layer. The fabricated pressure sensor exhibits a high sensitivity of 4.7 kPa−1 for low pressure from 0 to 1 kPa, a wide detection range of 0–700 kPa, ultra-fast response and recovery times of 46 ms and 62 ms, respectively, and an extremely low detection limit of 0.32 Pa. The sensor remains stable even after 4500 cycles and can accurately monitor the movement of the human joints. Furthermore, it can track human physiological signals, which is beneficial for medical diagnosis and disease prevention, and has significant potential for application in the wearable technology field.

Extrinsic Self‐Trapped‐Exciton Emission in Cs5Cu3Cl6I2 for Efficient X‐Ray Scintillation

AbstractEfficient and stable scintillators play a crucial role in X‐ray detection applications. To enhance the luminescence efficiency under X‐ray excitation, the incorporation of multiple emission centers into scintillators is widely explored. Here, it is found that the cesium copper halide Cs5Cu3Cl6I2 exhibits dual emission centers, enabling high‐performance scintillators with an X‐ray light yield of 49000 photon MeV−1 and a low detection limit of 4 nGy s−1. The emissions of Cs5Cu3Cl6I2 are from intrinsic self‐trapped exciton (STE) and Frenkel defect‐assisted STE. High‐energy X‐rays can induce an increased fraction of Frenkel defect‐assisted STEs, which can serve as an effective scintillation channel. Furthermore, large‐area flexible scintillators with a high resolution of 18 lp mm−1 are developed, making them suitable for X‐ray imaging applications. These findings offer promising insights for developing more efficient scintillators.

2D/0D Heterojunction Fluorescent Probe with Schottky Barrier Based on Ti3C2TX MXene Loaded Graphene Quantum Dots for Detection of H2S During Food Spoilage

AbstractHydrogen sulfide (H2S) contamination of food has raised widespread public health concerns, leading to substantial medical and economic burdens. Herein, a 2D/0D heterojunction fluorescent probe (TCTG) with Schottky barriers (SB) is designed and synthesized, utilizing Ti3C2Tx MXene‐loaded graphene quantum dots (GQDs), for the detection of H2S during food spoilage. The microstructures observed through SEM and TEM reveal that uniformly sized GQDs are evenly attached to the surface of a monolayer Ti3C2Tx. The chemisorption between GQDs and Ti3C2Tx facilitates charge transfer and the formation of SB, resulting in intramolecular charge transfer (ICT) effects. With the introduction of H2S, TCTG(50%) exhibits the highest sensitivity, selectivity, and anti‐interference properties, with ultra‐fast fluorescence transient reaction (3s) and remarkably low detection limit of 41.82 ppb as well as noticeable color change. When TCTG(50%) reacted with H2S, the ICT effects are inhibited, leading to the recovery of photoinduced electron transfer (PET) and fluorescence quenching. Notably, probe TCTG is effectively utilized to detect changes in H2S levels in raw foods to assess their quality. Overall, the significance of this study is its potential to revolutionize food spoilage detection, offering a fast, reliable, and sensitive method to ensure food safety and reduce associated health and economic burdens.

Oriented Alignment of CsPbBr3 Single-Crystal Arrays for Flexible X-ray Imaging.

The utilization of perovskite materials in flexible optoelectronics is experiencing distinct diversification including X-ray detection applications. Here, we report the oriented alignment of cesium lead bromide (CsPbBr3) single-crystal arrays on flexible polydimethylsiloxane (PDMS) substrates. By precisely confining the crystallization process within spatially delimited precursor droplets, we achieve a well-oriented crystal alignment through the spontaneous rotation of the CsPbBr3 microcuboids. This approach allows for precise control over the microcuboid morphologies by varying the growth temperature. We design flexible X-ray detector arrays by seamlessly integrating CsPbBr3 microcuboids with electrode arrays. The flexible X-ray detector can output a high sensitivity of 1.97 × 105 μC·Gyair-1·cm-2 and a low detection limit of 89 nGyair·s-1 after the surface passivation process. The excellent mechanical properties, outstanding X-ray detection capabilities, and high pixel uniformity are also demonstrated in conformal X-ray imaging of curved surfaces.

High performance and low detection limit isopropanol gas sensor based on 3D ZnSnO3 nanocubes co-catalyzed by Au nanoparticles and ZrO2

In this paper, Au nanoparticles (AuNPs) loaded ZrO2/ZnSnO3 nanocubes are prepared through hydrothermal route and chemical reduction method. The crystal structure, morphology, element distribution, chemical composition, specific surface area and pore size of ZrO2/ZnSnO3 nanocubes are described with XRD, TEM, XPS and BET. Interestingly, the incorporation of Zr ions induces the fragmentation of the edge of ZnSnO3 nanocubes, which enhance specific surface area of ZrO2/ZnSnO3 nanocubes. The response of ZnSnO3 materials for isopropanol is increased through doping ZrO2 and modifying AuNPs. The 1.5 at% AuNPs-loaded 5 at% ZrO2/ZnSnO3 nanocubes presents a higher response to 100 ppm isopropanol with a fast response/recovery time (3/4 s) at the operating temperature of 260℃. And the generation of ZnSnO3, ZrO2 and AuNPs heterojunctions contributes to raise the isopropanol response. In addition, the catalysis of ZrO2 and AuNPs also can increase their reaction speed between absorbed oxygen and isopropanol molecules. This research results provide a new scheme for the development of isopropanol sensor.

A novel system with robust compatibility and stability for detecting Sugarcane yellow leaf virus based on CRISPR-Cas12a.

Sugarcane yellow leaf virus (SCYLV) can reduce sugarcane productivity. A novel detection system based on reverse transcription-multienzyme isothermal rapid amplification (RT-MIRA) combined with CRISPR-Cas12a, named RT-MIRA-CRISPR-Cas12a, was developed. This innovative approach employs crude leaf extract directly as the reaction template, streamlining the extraction process for simplicity and speed. Combining RT-MIRA and CRISPR-Cas12a in one reaction tube increases the ease of operation while reducing the risk of aerosol contamination. In addition, it exhibits sensitivity equivalent to qPCR, boasting a lower detection limit of 25 copies. Remarkably, the entire process, from sample extraction to reaction completion, requires only 52-57 minutes, just a thermostat water bath. The result can be observed and judged by the naked eye.IMPORTANCESugarcane yellow leaf disease (SCYLD) is an important viral disease that affects sugarcane yield. There is an urgent need for rapid, sensitive, and stable detection methods. The reverse transcription-multienzyme isothermal rapid amplification combined with CRISPR-Cas12a (RT-MIRA-CRISPR-Cas12a) method established in this study has good specificity and high sensitivity. In addition, the system showed good compatibility and stability with the crude leaf extract, as shown by the fact that the crude extract of the positive sample could still be stably detected after 1 week when placed at 4°C. RT-MIRA-CRISPR-Cas12a, reverse transcription polymerase chain reaction (RT-PCR), and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to detect SCYLV on 33 sugarcane leaf samples collected from the field, and it was found that the three methods reached consistent conclusions. This Cas12a-based detection method proves highly suitable for the rapid on-site detection of the SCYLV.

Pd Nanoparticles Loaded on Cu Nanoplate Sensor for Ultrasensitive Detection of Dopamine.

The detection of dopamine is of great significance for human health. Herein, Pd nanoparticles were loaded on Cu nanoplates (Pd/Cu NPTs) by a novel liquid phase reduction method. A novel dopamine (DA) electrochemical sensor based on the Pd NPs/Cu/glass carbon electrode (Pd/Cu NPTs/GCE) was constructed. This sensor showed a wide linear range of 0.047 mM to 1.122 mM and a low limit of detection (LOD) of 0.1045 μM (S/N = 3) for DA. The improved performance of this sensor is attributed to the obtained tiny Pd nanoparticles which increase the catalytic active sites and electrochemical active surface areas (ECSAs). Moreover, the larger surface area of two-dimensional Cu nanoplates can load more Pd nanoparticles, which is another reason to improve performance. The Pd/Cu NPTs/GCE sensor also showed a good reproducibility, stability, and excellent anti-interference ability.

Hive-shaped carbon nanotubes coated with MoSe2as an electrochemical sensor for cholesterol.

The study utilized transition metal chalcogenide, molybdenum diselenide (MoSe2), for application in the field of bioelectrochemical sensing. The MoSe2was combined with carbon nanotubes (CNTs) by chemical vapor deposition to enhance the specific surface area and improve the detection sensitivity. To further increase the contact area between the electrolyte and the electrode, photolithography techniques were employed to fabricate hive-shaped CNTs, thereby enhancing the specific surface area. Next, cholesterol oxidase (ChOx) was coated onto the electrode material, creating a cholesterol biosensor. Cyclic voltammetry was utilized to detect the concentration of cholesterol. The experiment involved segmented testing for cholesterol concentrations ranging from 0μM to 10 mM. Excellent sensitivity, low detection limits, and high accuracy were achieved. In the cholesterol concentration range of 0μM-100μM, the experiment achieved the highest sensitivity of 4.44μAμM⋅cm-2. Consequently, all data indicated that ChOx/MoSe2/CNTs functioned as an excellent cholesterol sensor in the study.

Fabrication of Nanobioengineered Interfaces Utilizing Quaternary Nanocomposite for Highly Efficient and Selective Electrochemical Biosensing of Urea.

Nanobioengineered interfaces have gained attention owing to their small size and high surface area-to-volume ratio for utilization as a platform for highly selective and sensitive biosensing applications owing to the integration of biological molecules with engineered nanomaterials/nanocomposites. In this work, a novel Ag-complex, [(PPh3)2Ag(SCOf)]-based quaternary Ag-S-Zn-O nanocomposites (NCs), was synthesized through an environmentally-friendly process. The results revealed the formation of the NCs with an average crystallite size and particle size of 36.08 and 40.22 nm, respectively. In addition, this is the first study to utilize such NCs synthesized via a single-source precursor method, offering enhanced sensor performance due to their unique structural properties. Further, these NCs were used to fabricate a urease (Ur)/Ag-S-Zn-O NCs/ITO nanobioengineered electrode for precise and sensitive electrochemical biosensing of urea. The interfacial kinetic studies revealed quasi-reversible processes with high electron transfer rates and linear current responses, indicating efficient reaction dynamics. A high diffusion coefficient and low surface concentration suggested a fast diffusion-controlled process, affirming the electrode's potential for rapid and sensitive urea detection. The biosensor demonstrated notable sensing properties such as high sensitivity (12.56 μA mM-1 cm-2) and a low detection limit (0.54 mM). The fabricated bioelectrode was highly selective and reproducible and demonstrated stability for up to 60 days. These results validate the potential of this nanobioengineered interface for next-generation biosensing applications, paving the way for advanced point-of-care diagnostics and real-time health monitoring.

A highly stable, rapid and sensitive fluorescent probe for Al3+ and pefloxacin based on enhanced fluorescence of a Co(II) coordination polymer

Fabricating functional coordination polymer (CP) architectures and exploiting it as fluorescence sensors for detecting diverse metal ions and antibiotics, have attracted extensive attention. Based on a rarely-used benzimidazole-derived ligand 2,2′-bis-(2-pyridin-3-yl-vinyl)-3H,3′H-[5,5]bibenzoimidazole (L), a new CP {[Co(L)0.5(tbip)]·H2O}n (H2tbip =5‑tert-butylisophthalic acid) (1) was synthesized under solvothermal condition and characterized. Complex 1 reveals a two-dimensional network with the type of topology of 3,4,5L7. Complex 1 possesses excellent thermal and chemical stability. The fluorescence detection ability of complex 1 was explored and demonstrated that complex 1 can be used as the first fluorescent turn-on sensor to sense Al3+ and pefloxacin (PEF) with a low detection limit and fast response. The fluorescence enhancement mechanism was investigated in detail.

An Ultrasensitive Molecularly Imprinted Point-Of-Care Electrochemical Sensor for Detection of Glial Fibrillary Acidic Protein.

Accurate assessment of neurological disease through monitoring of biomarkers has been made possible using the antibody-based assays. But these assays suffer from expensive development of antibody probes, reliance on complicated equipments, and high maintenance costs. Here, using the novel reduced graphene oxide/polydopamine-molecularly imprinted polymer (rGO/PDA-MIP) as the probe layer, a robust electrochemical sensing platform is demonstrated for the ultrasensitive detection of glial fibrillary acidic protein (GFAP), a biomarker for a range of neurological diseases. A miniaturized integrated circuit readout system is developed to interface with the electrochemical sensor, which empowers it with the potential to be used as a point-of-care (POC) diagnostic tool in primary clinical settings. This innovative platform demonstrated good sensitivity, selectivity, and stability, with imprinting factor evaluated as 2.8. A record low limit-of-detection (LoD) is down to 754.5 agmL-1, with a wide dynamic range from 1 to 106 fgmL-1. The sensing platform is validated through the analysis of GFAP in clinical plasma samples, yielding a recovery rate range of 81.6-108.8% compared to Single Molecule Array (Simoa). This cost-effective and user-friendly sensing platform holds the potential to be deployed in primary and resource-limited clinical settings for the assessment of neurological diseases.

Quantum Confinement and End-Sealing Effects for Highly Sensitive and Stable Nitrogen Dioxide Detection: Homogeneous Integration of Ti3C2Tx-Based Flexible Gas Sensors.

The real-time and room-temperature detection of nitrogen dioxide (NO2) holds significant importance for environmental monitoring. However, the performance of NO2 sensors has been hampered by the trade-off between the high sensitivity and stability of conventional sensitive materials. Here, we present a novel fully flexible paper-based gas sensing structure by combining a homogeneous screen-printed titanium carbide (Ti3C2Tx) MXene-based nonmetallic electrode with a MoS2 quantum dots/Ti3C2Tx (MoS2 QDs/Ti3C2Tx) gas-sensing film. These precisely designed gas sensors demonstrate an improved response value (16.3% at 5 ppm) and a low theoretical detection limit of 12.1 ppb toward NO2, which exhibit a remarkable 3.5-fold increase in sensitivity compared to conventional Au interdigital electrodes. The outstanding performance can be attributed to the integration of the quantum confinement effect of MoS2 QDs and the conductivity of Ti3C2Tx, establishing the main active adsorption sites and enhanced charge transport pathways. Furthermore, an end-sealing effect strategy was applied to decorate the defect sites with naturally oxygen-rich tannic acid and conductive polymer, and the formed hydrogen bonding network at the interface effectively mitigated the oxidative degradation of the Ti3C2Tx-based gas sensors. The exceptional stability has been achieved with only a 1.8% decrease in response over 4 weeks. This work highlights the innovative design of high-performance gas sensing materials and homogeneous gas sensor techniques.

Magnetic solid phase extraction of methiocarb pesticide from food samples prior to HPLC analysis with magnetic activated carbon cloth/zinc aluminate (magnetic ACC@ZnAl2O4) composite

Methiocarb is a carbamate pesticide and is widely used due to its short lifetime but is a health concern due to its toxicity. To address this challenge, a novel nano-sorbent (zinc aluminate hybrid doped onto a magnetic activated carbon cloth (magnetic ACC@ZnAl2O4)) was synthesized. The characterization of the composite was done using FTIR spectroscopy, SEM, XRD, and EDX. The synthesized composite was then employed for the efficient extraction of methiocarb from food samples. Under the optimum conditions of (pH: 7.0, vortex time: 0.5 min, adsorbent dose: 5 mg, initial volume of sample: 50 mL, volume of eluent: 1.0 mL), quantitative recovery values of methiocarb in food samples were obtained (80–114%). This method impresses with its exceptional sensitivity, achieving incredibly low detection (LOD: 20 µg L−1) and quantification (LOQ: 67 µg L−1) limits for methiocarb. Its efficiency is equally impressive, with high values of preconcentration factor (PF: 50) and enhancement factor (EF: 49.4), ensuring accurate and reliable analysis with a low value of relative standard deviation (RSD: 4.8%). The method’s impressive selectivity, evident in its minimal interference from other pesticides, paves the way for reliable methiocarb analysis in food samples.

Rational Design of A-Site Cation for High Performance Lead-Free Perovskite X-Ray Detectors.

Design of hypotoxic lead-free perovskites, e.g. Bismuth(Bi)-based perovskites, is much beneficial for commercialization of perovskite X-ray detectors due to their strong radiation absorption. Nevertheless, the design principles governing the selection of A-site cations for achieving high-performance X-ray detectors remain elusive. Here, seven molecules (methylamine MA, amine NH3, dimethylbiguanide DGA, phenylethylamine PEA, 4-fluorophenethylamine p-FPEA, 1,3-propanediamine PDA, and 1,4-butanediamine BDA) and calculated their dipole moments and interaction strength with metal halide (BiI3) are selected. The first-principles calculations and related spectroscopy measurements confirm that organic molecules (DGA) with large dipole moments can have strong interactions with perovskite octahedron and improve the carrier transport between the organic and inorganic clusters. Consequently, zero-dimensional single crystal (SC) (DGA)BiI5∙H2O is synthesized. The (DGA)BiI5∙H2O SCs demonstrate an exceptional carrier mobility-lifetime product of 6.55×10-3cm2V-1, resulting in the high sensitivity of 5879.4µCGyair -1cm-2, featuring a low detection limit (4.7nGyairs-1) and remarkable X-ray irradiation stability even after 100 days of aging at a high electric field (100Vmm-1). Furthermore, the (DGA)BiI5∙H2O SCs for imaging, achieving a notable spatial resolution of 5.5lpmm-1 are applied. This investigation establishes a pathway for systematically screening A-site cations to design low-dimensional SCs for high-performance X-ray detection.

Framework-Induced Electrochemiluminescence Enhancement of an AIEgen-Based MOF Coupled with Heterostructured TiO2@Ag NPs as an Efficient Coreaction Accelerator for Sensitive Biosensing.

In conventional metal-organic framework (MOF) luminophore-involved electrochemiluminescence (ECL) systems, the aggregation-caused quenching commonly exists for the organic luminescent ligands, limiting the ECL efficiency and detection sensitivity. Herein, by employing the aggregation-induced emission luminogen (AIEgen) 1,1,2,2-tetra(4-carboxylbiphenyl)ethylene (H4TCBPE) as a ligand, one high-efficiency ECL emitter (Zr-MOF) was synthesized through a simple hydrothermal reaction. Compared with H4TCBPE monomers and their aggregates, the resultant Zr-MOF possesses the strongest ECL emission, which is mainly attributed to the framework-induced ECL enhancement. Specifically, the heterostructure was prepared by the deposition of silver nanoparticles on TiO2 microflowers and utilized as an efficient coreaction accelerator. Remarkably, the formative heterojunction can increase the interfacial charge transfer efficiency and promote the carrier separation, facilitating the oxidation of coreactant tripropylamine. In this way, a novel aptamer-mediated ECL sensing platform is constructed, achieving the sensitive analysis of adenosine triphosphate with a low detection limit of 0.17 nM. As a proof-of-concept study, this work may enlighten the rational design of new-type MOF-based ECL materials and expand the application scope of the ECL technology.

A Novel, Selective, and Fast Electrochemical Sensor Based on an 8-Nitroquinoline-Coated Pencil Graphite Electrode for Rutin Determination in Orange Juice

In this study, we developed a facile and low-cost method to prepare a modified electrode by coating the pencil graphite electrode (PGE) surface with 8-nitroquinoline (8-NQ). The surface modification process was carried out by electrochemical reduction of 8-NQ on the PGE surface in ethanol solution. The optimum conditions were determined for the experimental studies. The differential pulse voltammetry was used to determine rutin with the modified electrode (8-NQ/PGE). The developed electrode showed excellent performance for rutin oxidation in a pH 3.0 Britton Robinson buffer (BR). In this media, linearly increasing anodic peak currents were observed with the concentration of rutin in two wide concentration ranges (i.e., 0.016–0.96 μM and 0.96‒19.73 μM), the sensor showed a low detection limit (i.e., 4.14 nM) (3 s m−1). It displayed good stability and selectivity. Also, it was used successfully for the determination of rutin in orange juice samples.

Design and preparation of a sensitive electrochemical aptasensor based on hierarchical porous UiO-66 for detecting ampicillin

Hierarchical porous UiO-66 (HP-UiO-66) was rationally prepared using sodium acetate and polyvinylpyrrolidone as auxiliaries. The defective structure of HP-UiO-66 was confirmed by various characterization methods. Compared with the pristine UiO-66, HP-UiO-66 possessed more accessible Zr sites to load aptamers. The electrochemical aptasensor based on HP-UiO-66 was used to detect ampicillin (AMP) as an analytical model with a low limit of detection (3.0 fg mL−1) by differential pulse voltammetry. This fabricated aptasensor exhibited good reproducibility, stability, and specificity toward AMP. The sensor could be used to quantitatively detect AMP even in real samples (tap water and milk).