Xiaojun Hu

[¹¹¹In]In-diethylenetriaminepentaacetic acid-5,10,15,20-tetraphenylporphyrin ([¹¹¹In]In-DTPA-TPP) nanodroplets were developed for cancer theranostics, featuring ultrasound-sensitive properties. The designed nanodroplets that encapsulate the low-boiling-point liquid perfluorocarbon and IR-780 iodide, a near-infrared fluorescent dye, with surface conjugation of ¹¹¹In-labeled porphyrin derivative, were synthesized and evaluated by in vitro and in vivo experiments. The cellular uptake of [¹¹¹In]In-DTPA-TPP nanodroplets was significantly higher than that of control nanodroplets without TPP. Biodistribution experiments revealed greater tumor accumulation in mice injected with [¹¹¹In]In-DTPA-TPP nanodroplets than in those injected with control nanodroplets lacking TPP. Additionally, the accumulation of [¹¹¹In]In-DTPA-TPP nanodroplets in the tumor was visualized by single-photon emission computed tomography. Sonodynamic therapeutic experiments revealed that DTPA-TPP nanodroplets at 10 µmol total lipids/kg weight with a single ultrasound irradiation onto the tumor area significantly inhibited tumor growth. These results indicate that [¹¹¹In]In-DTPA-TPP nanodroplets would be promising cancer theranostic agents.

Bone-seeking radiopharmaceuticals are essential for the early detection of bone metastases. In this study, we developed three Technetium-99m (99mTc)-labeled oligopeptides composed of acidic amino acids and evaluated their bone-targeting ability. Hydrazinonicotinamide (HYNIC)-conjugated oligopeptides with five residues of aspartic acid (Asp), glutamic acid (Glu), or γ-carboxyglutamic acid (Gla) were synthesized and radiolabeled with 99mTc using tricine and 3-acetylpyridine as co-ligands. Their hydroxyapatite binding, in vitro stability, biodistribution, and single-photon emission computed tomography (SPECT)/CT imaging in normal mice were evaluated. Among the three tracers, [99mTc]Tc-HYNIC-(tricine)(AcP)-(dl-Gla)5 ([99mTc]3) showed the highest hydroxyapatite binding and bone uptake, with clear visualization in SPECT/CT. All compounds exhibited high radiochemical purity and in vivo stability. Oligopeptides containing Gla residues exhibited superior bone affinity and imaging performance, suggesting that Gla-based oligopeptides are promising scaffolds for the development of 99mTc-labeled bone imaging agents.

Boron neutron capture therapy (BNCT) is one of the promising cancer treatment methods with ¹⁰B-labeled compounds and neutron irradiation. The ¹⁰B(n,α)⁷Li reaction produces a ⁷Li nucleus and an α-particle with high linear energy transfer, which are responsible for the therapeutic effects. We hypothesized that BNCT could effectively treat bone metastases by selectively accumulating ¹⁰B at metastatic lesion sites. In this study, we designed, synthesized, and evaluated [^nat/67Ga]Ga-DOTA-K(ε-closo-dodecaborate)D₁₁ ([^nat/67Ga]6), a compound integrating closo-dodecaborate for BNCT, a [^nat/67Ga]Ga-DOTA derivative for nuclear imaging, and D₁₁, an aspartic acid peptide, for bone targeting. [⁶⁷Ga]6 and its precursor 5, which lacks gallium coordination, showed comparable biodistribution in normal mice, with high bone uptake and minimal off-target accumulation. These results support the potential of [^nat/67/68Ga]6 as an effective theranostic agent for bone metastases.

Plasmon-enhanced photo/electrocatalysis using hetero-nanostructures has emerged as a promising approach for boosting the efficiency and selectivity of photo/electrocatalytic reactions. Plasmonic nanostructures (PNSs), with their unique properties including localized surface plasmon resonance (LSPR), play a vital role in enhancing photo/electrocatalytic activities. By leveraging LSPR, PNSs can concentrate incident light, facilitate charge separation, and induce surface reactions, leading to improved catalytic performance. In this review, we provide a comprehensive analysis of the current state of knowledge in this field. We discuss the rational design and synthesis of hetero-nanostructures, focusing on the optimization of composition, size, shape, and interface properties. Furthermore, we explore various combinations of plasmonic sources with semiconductors of diverse morphologies to achieve enhanced photocatalytic activity. The reviewed research encompasses applications in water splitting, removal of organic pollutants, CO2 reduction, and energy conversion. We also address the challenges that need to be overcome, including optimization of materials, reproducibility, stability, band alignment, and understanding plasmon–material interactions in hetero-nanostructures. The review of future perspectives includes the integration of multiple functionalities, the exploration of novel plasmonic materials, and the translation of plasmon-enhanced photo/electrocatalysis into practical applications. The combination of plasmonics and nanotechnology can be used to advance green technologies and address pressing global issues.

A sensing interface co-constructed from the two-dimensional conductive material (Ag@MXene) and an antifouling cyclic multifunctional peptide (CP) is described. While the large surface area of Ag@MXene loads more CP probes, CP binds to Ag@MXene to form a fouling barrier and ensure the structural rigidity of the targeting sequence. This strategy synergistically enhances the biosensor’s sensitivity and resistance to contamination. The SPR results showed that the binding affinity of the CP to the target was 6.23 times higher than that of the antifouling straight-chain multifunctional peptide (SP) to the target. In the 10 mg/mL BSA electrochemical fouling test, the fouling resistance of Ag@MXene + CP (composite sensing interface of CP combined with Ag@MXene) was 30 times higher than that of the bare electrode. The designed electrochemical sensor exhibited good selectivity and wide dynamic response range at PD-L1 concentrations from 0.1 to 50 ng/mL. The lowest detection limit was 24.54 pg/mL (S/N = 3). Antifouling 2D materials with a substantial specific surface area, coupled with non-straight chain antifouling multifunctional peptides, offer a wide scope for investigating the sensitivity and antifouling properties of electrochemical sensors. Graphical abstract

Nitrated α-syn (nitro-α-syn) is a biomarker for Parkinson's desease (PD), and its sensitive detection in serum is of great importance for early PD diagnosis. Silver-coated copper MOF (Cu-MOF@Ag) with outstanding oxidase activity and electrochemical response property was designed and synthesized. Cu-MOF@Ag exhibited excellent oxidase activity with a low K_m value (0.568 mM), avoiding the addition of strong oxidant to catalyze chromogenic substrate, which enhanced the colorimetric stability. Silver nanoparticles as an electrochemical signal reporter can be easily decorated on the surface of Cu-MOF with bifunctional groups (-SH and -NH₂) material, which can increase the electrochemical signal output. The α-syn antibody modified Cu-MOF@Ag and nitro-α-syn modified magnetic nanoparticle were used as immunoprobes to specifically capture nitro-α-syn. A dual-modal immunosensor was fabricated for the simple and reliable detection of nitro-α-syn based on Cu-MOF@Ag. Combing colorimetric and electrochemical detection, nitro-α-syn can be determined quantitatively within a wide linear range (10–350 ng/mL) with low detection limit (0.5 ng/mL). The ability of the sensor with magnetic separation and dual signal analysis allowed to successfully detect nitro-α-syn and distinguish PD patients from healthy people (P < 0.005). Thanks to its excellent selectivity, stability, and the precision of 2.69%, the dual-modal sensor has potential clinical application for nitro-α-syn detection and paves a new way for PD diagnosis at its early stage. Graphical abstract

In this study, an enhanced activity and stability method for immobilizing porcine pancreatic lipase (PPL) was developed based on ZIF-8 encapsulated supramolecular-modified gold nanoparticle complexes (pSC₄-AuNPs@ZIF-8). Supramolecular calix[4]arene (pSC₄) can recognize the amino group of PPL through non-covalent force, and this flexible binding method protected the structure of PPL during the immobilization process. Due to the hydrophilic of pSC₄-AuNPs and hydrophobic of ZIF-8, PPL can maintain a “lid open” conformation, which can enhance the stability of PPL structure and reduce PPL activity loss. ZIF-8 was used to immobilize PPL to avoid the difficult recovery of free PPL. Compared with the native form of PPL, it exhibited 70.6% maintained activity with terrific pH and temperature stability, and had good performance in thermal stability, time stability, and reusability. In addition, three immobilized PPL methods were designed to further clarify the influence of synthetic methods and additives on the activity and stability of PPL. Importantly, the loading rate of pSC₄-AuNPs@ZIF-8@PPL was up to 51.2% among these immobilized PPL systems. Therefore, pSC₄-AuNPs@ZIF-8 may serve as a versatile and promising immobilization system for enzymes.