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Sol-gel materials have been widely used for solid-phase microextraction (SPME) coatings due to their outstanding performance; in contrast, sol-gel SPME coatings have seldom been used for in vivo sampling. The main reason is that their matrix compatibility is unclear. In order to promote the application of this type of coating and accelerate the development of in vivo SPME, in this study, the matrix compatibility of several typical sol-gel coatings was assessed in plasma and whole blood using phthalic acid esters as analytes. The service life of five kinds of sol-gel coatings was among 20-35 times in undiluted plasma, while it was 27 times for a homemade commercial polydimethylsiloxane coating, which indicates good matrix compatibility of sol-gel coatings in untreated plasma. The sol-gel hydroxy-terminated silicone oil/methacrylic acid fiber achieved the highest extraction ability among all of the fibers, and it was tested in pig whole blood. It could be continuously used for at least 22 times, demonstrating good potential for in vivo sampling. Subsequently, a direct-immersion SPME/gas chromatography-flame ionization detection method was established for the determination of 5 phthalic acid esters in blood. Compared with other methods reported in the literature, this method is rapid, simple, sensitive, and accurate, and does not need expensive instruments or tedious procedures. A simulation system of animal blood circulation was constructed to verify the practicability of sol-gel SPME coatings in animal vein sampling. The result illustrated the feasibility of that coating for in vivo blood sampling, but a more accurate quantification calibration approach needs to be explored.
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Ácidos Ftálicos , Microextração em Fase Sólida , Animais , Cromatografia Gasosa/métodos , Ésteres , Microextração em Fase Sólida/métodos , SuínosRESUMO
Electrical impedance tomography (EIT) is a radiation-free and noninvasive medical image reconstruction technique in which a current is injected and the reflected voltage is received through electrodes. EIT electrodes require good connection with the skin for data acquisition and image reconstruction. However, detached electrodes are a common occurrence and cause measurement errors in EIT clinical applications. To address these issues, in this study, we proposed a method for detecting faulty electrodes using the differential voltage value of the detached electrode in an EIT system. Additionally, we proposed the voltage-replace and voltage-shift methods to compensate for invalid data from the faulty electrodes. In this study, we present the simulation, experimental, and in vivo chest results of our proposed methods to verify and evaluate the feasibility of this approach.
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Tomografia , Dispositivos Eletrônicos Vestíveis , Tomografia/métodos , Impedância Elétrica , Eletrodos , TêxteisRESUMO
The cyclic depsipeptide cereulide toxin it is a very well-known potassium electrogenic ionophore particularly sensitive to pancreatic beta cells. The mechanistic details of its specific activity are unknown. Here, we describe a series of synthetic substituted cereulide potassium ionophores that cause impressive selective activation of glucose-induced insulin secretion in a constitutive manner in rat insulinoma INS1E cells. Our study demonstrates that the different electroneutral K+ transport mechanism exhibited by the anionic mutant depsipeptides when compared with classical electrogenic cereulides can have an important impact of pharmacological value on glucose-stimulated insulin secretion.
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Depsipeptídeos/farmacologia , Secreção de Insulina/efeitos dos fármacos , Ionóforos/química , Potássio/química , Animais , Transporte Biológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Depsipeptídeos/síntese química , Depsipeptídeos/química , Glucose/farmacologia , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Microscopia Confocal , Potássio/metabolismo , RatosRESUMO
The self-assembly of triazole amphiphiles was examined in solution, the solid state, and in bilayer membranes. Single-crystal X-ray diffraction experiments show that stacked protonated triazole quartets (T4 ) are stabilized by multiple strong interactions with two anions. Hydrogen bonding/ion pairing of the anions are combined with anion-π recognition to produce columnar architectures. In bilayer membranes, low transport activity is observed when the T4 channels are operated as H+ /X- translocators, but higher transport activity is observed for X- in the presence of the K+ -carrier valinomycin. These self-assembled superstructures, presenting intriguing structural behaviors such as directionality, and strong anion encapsulation by hydrogen bonding supported by vicinal anion-π interactions can serve as artificial supramolecular channels for transporting anions across lipid bilayer membranes.
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OBJECTIVE: To prepare iodine-131(131I) labeled biodegradable microspheres with chitosan and collagen for treating liver cancer. METHODS: Collagen-chitosan microspheres (CCMSs) were prepared with type-â collagen and chitosan using emulsification-chemical cross-linking method. The size of the CCMSs were determined by electron microscope. 131I-CCMSs were achieved using Chloramine-T. The labelling rate of 131I was recorded. The stability of 131I-CCMSs in vitro were evaluated in PBS or human blood serum through 192 h incubation. The HepG2 model was established in nude mice 28 d after subcutaneous injection of 106 HepG2 cells. The model mice were sacrificed 7 d after injection of 131I-CCMSs,blank microspheres,or PBS (five mice in each group) into the HepG2 tumor xenografts. Samples of various organs were collected to determine the distribution of 131I-CCMSs. The curative effect of 131I-CCMSs on liver cancer was assessed by staining with HE for histological analyses. RESULTS: CCMSs were synthesized with a smooth and spherical shape and an average diameter of (5.1±1.2) µm. A radiolabeling rate of 86.10% was achieved. 131I radio-loading remained stable: 92.00% in saline and 83.00% in human serum after 192 h incubation. 131I was mainly concentrated in the subcutaneous tumor tissues. Potent curative effects of 131I-CCMSs on subcutaneous tumor tissues were demonstrated. CONCLUSION: Biodegradable CCMSs were successfully prepared and radiolabeled. The 131I-CCMSs exhibited potential curative effects on liver cancer,with high stability in vitro and in vivo.
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Quitosana/química , Colágeno/química , Radioisótopos do Iodo/farmacologia , Neoplasias Hepáticas/radioterapia , Microesferas , Animais , Células Hep G2 , Humanos , Camundongos , Camundongos Nus , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Self-assembled alkyl-ureido-benzo-15-crown-5-ethers are selective ionophores for K+ cations, which are preferred to Na+ cations. The transport mechanism is determined by the optimal coordination rather than classical dimensional compatibility between the crown ether hole and the cation diameter. Herein, we demonstrate that systematic changes of the structure lead to unexpected modifications in the cation-transport activity and suffice to produce adaptive selection. We show that the main contribution to performance arises from optimal constraints on the conformational freedom, which are determined by the binding macrocycles, the nature of the hydrogen-bonding groups, and the hydrophobic tails. Simple changes to the flexible 15-crown-5-ether lead to selective carriers for Na+ . Hydrophobic stabilization of the channels through mutual interactions between lipids and variable hydrophobic tails appears to be an important cause of increased activity. Oppositely, restricted translocation is achieved when constrained hydrogen-bonded macrocyclic relays are less dynamic in a pore superstructure.
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Éteres de Coroa/química , Canais de Potássio/química , Canais de Sódio/química , Sítios de Ligação , Éteres de Coroa/metabolismo , Cristalografia por Raios X , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Transporte de Íons , Ionóforos/química , Ionóforos/metabolismo , Isomerismo , Conformação Molecular , Canais de Potássio/metabolismo , Canais de Sódio/metabolismoRESUMO
Silicon nanoparticles (Si NPs) have been widely used in fluorescence imaging. However, rigorous synthesis conditions and the single modality imaging limit the further development of Si NPs in the field of biomedical imaging. Here, we reported a method for synthesizing water-dispersible Mn2+ functionalized Si NPs (Mn-Si NPs) under mild experimental conditions for fluorescence and magnetic resonance dual-modality imaging. The whole synthesis process was completed under room temperature and atmospheric pressure, and no special and expensive equipment was required. The synthetic nanoparticles, with favorable pH stability, NaCl stability, photostability, and low toxicity, emitted green fluorescence (512 nm). At the same time, the nanoparticles also demonstrated excellent magnetic resonance imaging ability. In vitro, their T1-weighted magnetic resonance imaging effect was obvious, and the value of longitudinal relaxation degree r1 reached 4.25 mM-1 s-1. On the basis of their good biocompatibility, Mn-Si NPs were successfully used for the fluorescence imaging as well as magnetic resonance imaging in vivo.
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Imaging-guided therapy systems (IGTSs) are revolutionary techniques used in cancer treatment due to their safety and efficiency. IGTSs should have tunable compositions for bioimaging, a suitable size and shape for biotransfer, sufficient channels and/or pores for drug loading, and intrinsic biocompatibility. Here, a biocompatible nanoscale zirconium-porphyrin metal-organic framework (NPMOF)-based IGTS that is prepared using a microemulsion strategy and carefully tuned reaction conditions is reported. A high content of porphyrin (59.8%) allows the achievement of efficient fluorescent imaging and photodynamic therapy (PDT). The 1D channel of the Kagome topology of NPMOFs provides a 109% doxorubicin loading and pH-response smart release for chemotherapy. The fluorescence guiding of the chemotherapy-and-PDT dual system is confirmed by the concentration of NPMOFs at cancer sites after irradiation with a laser and doxorubicin release, while low toxicity is observed in normal tissues. NPMOFs are established as a promising platform for the early diagnosis of cancer and initial therapy.
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Doxorrubicina/uso terapêutico , Estruturas Metalorgânicas , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Fotoquimioterapia/métodos , Porfirinas/química , HumanosRESUMO
Two analogous M4 L4 -type tetrahedral cages (smaller: MOC-19; larger: MOC-22) were synthesized and investigated for their interactions with the anticancer drug 5-fluoracil (5-FU) by NMR spectroscopy, high-resolution electrospray-ionization mass spectrometry (HR-ESI-MS), and molecular simulation. The cage's size and window are of importance for the host-guest binding, and consequently the smaller MOC-19 with a more suitable size of cavity window was found to have much stronger hydrogen-bond interactions with 5-FU. The porous nanoparticles of MOC-19 exhibited outstanding behavior for the controlled release of 5-FU in a simulated human body with liquid phosphate-buffered saline solution.
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Antineoplásicos/administração & dosagem , Preparações de Ação Retardada/química , Fluoruracila/administração & dosagem , Estruturas Metalorgânicas/química , Antineoplásicos/química , Fluoruracila/química , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Nanopartículas/química , Tamanho da Partícula , Porosidade , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Silicon nanoparticles (SiNPs) have been reported to be synthesized by microwave-assisted methods under high pressure. However, there is still a lack of knowledge about the synthesis of SiNPs via microwave-assisted methods under normal pressure. Here we developed a new, facile, one-pot microwave-assisted method for the synthesis SiNPs (â¼4.2 nm) with excellent water solubility under normal pressure by employing glycerol as the solvent. Furthermore, glycerol might be responsible for the photoluminescence quantum yield (PLQY) value up to 47% for the resultant SiNPs. The use of organic solvent could afford less nanoparticle surface defects compared with those prepared in aqueous solution, thus improving the fluorescent efficiency. The as-prepared SiNPs simultaneously featured bright blue-green fluorescence, long lifetime (â¼12.8 ns), obvious up-conversion luminescence originating from two-photon absorption, superbly strong photostability, and favorable low toxicity. As a satisfactory probe, the as-synthesized SiNPs were successfully applied in fluorescence imaging of human cervical carcinoma cell lines (HeLa) and zebrafish.
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Fluorescência , Micro-Ondas , Nanopartículas/química , Imagem Óptica , Silício/química , Água/química , Animais , Células HeLa , Humanos , Peixe-ZebraRESUMO
To combine flexibility and modifiability towards a more controllable complexity of MOFs, a post-synthetic variable-spacer installation (PVSI) strategy is used to implement kinetic installation/ uninstallation of secondary ligands into/from a robust yet flexible proto-Zr-MOF. This PVSI process features precise positioning of spacers with different length, size, number, and functionality, enabling accurate fixation of successive breathing stages and fine-tuning of pore surface. It shows unprecedented synthetic tailorability to create complicated MOFs in a predictable way for property modification, for example, CO2 and R22 adsorption/separation, thermal/chemical stability, and extended breathing behavior.
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(13)C-engineered carbon quantum dots ((13)C-QDs) were used as magnetic resonance (MR) and fluorescence dual-response probe. The enhanced (13)C-MR signal was observed at 171 ppm from carboxylic and carboxyl carbons in (13)C-QDs with 160-fold improvement on signal-to-noise ratio even when no hyperpolarization was applied, whereas the intrinsic fluorescence of C-QDs was still maintained. The stable MR and fluorescence dual-response was successfully used for long-term observation of zebrafish embryonic development. Cross-validation between MR and fluorescence confirmed the distribution of (13)C-QD in zebrafish. (13)C-MR provides specific information about the presence, magnitude, and progression of (13)C-QDs by defining MR intensity, whereas fluorescence reveals the location of (13)C-QDs with its high sensitivity. (13)C-MR and fluorescence was simultaneously observed within (13)C-QDs, and this work may expand the applications of isotope-engineered nanomaterials.
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Espectroscopia de Ressonância Magnética , Microscopia de Fluorescência , Pontos Quânticos/metabolismo , Animais , Isótopos de Carbono/química , Embrião não Mamífero/química , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário , Pontos Quânticos/química , Peixe-ZebraRESUMO
As the burgeoning field of Artificial Intelligence (AI) continues to permeate the fabric of healthcare, particularly in the realms of patient surveillance and telemedicine, a transformative era beckons. This manuscript endeavors to unravel the intricacies of recent AI advancements and their profound implications for reconceptualizing the delivery of medical care. Through the introduction of innovative instruments such as virtual assistant chatbots, wearable monitoring devices, predictive analytic models, personalized treatment regimens, and automated appointment systems, AI is not only amplifying the quality of care but also empowering patients and fostering a more interactive dynamic between the patient and the healthcare provider. Yet, this progressive infiltration of AI into the healthcare sphere grapples with a plethora of challenges hitherto unseen. The exigent issues of data security and privacy, the specter of algorithmic bias, the requisite adaptability of regulatory frameworks, and the matter of patient acceptance and trust in AI solutions demand immediate and thoughtful resolution .The importance of establishing stringent and far-reaching policies, ensuring technological impartiality, and cultivating patient confidence is paramount to ensure that AI-driven enhancements in healthcare service provision remain both ethically sound and efficient. In conclusion, we advocate for an expansion of research efforts aimed at navigating the ethical complexities inherent to a technology-evolving landscape, catalyzing policy innovation, and devising AI applications that are not only clinically effective but also earn the trust of the patient populace. By melding expertise across disciplines, we stand at the threshold of an era wherein AI's role in healthcare is both ethically unimpeachable and conducive to elevating the global health quotient.
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Inteligência Artificial , Medicina de Precisão , Telemedicina , Inteligência Artificial/ética , Humanos , Medicina de Precisão/métodos , Atenção à SaúdeRESUMO
Harnessing the photoinduced phase transitions in organic crystals, especially the changes in shape and structure across various dimensions, offers a fascinating avenue for exact spatiotemporal control, which is crucial for developing future smart devices. In our study, we report a new photoactive molecular crystal made from (E)-2-(3-phenyl-allylidene)malonate ((E)-PADM). When exposed to ultraviolet (UV) light at 365 nm, this compound experiences an E-to-Z photoisomerization in liquid solution and a crystal-to-liquid phase transition in solid crystals. Remarkably, nanoscopic crystalline rods boost their melting rate and degree compared to bulk crystals, indicating that miniaturization enhances the photoinduced melting effect. Our results demonstrate a simple approach to rapidly drive molecular crystals into liquids via photochemical reactions and phase transitions.
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In metal hydride-catalyzed alkene hydrofunctionalization reactions via hydrogen atom transfer, simple carbonyl groups have been well-recognized as good somophiles at the carbon for C-C bond formation. Here we report an alternative pathway exploring the carbonyl as an O-nucleophile to make new C-O bonds during the CoH-catalyzed oxidative cyclization of alkenyl aldehydes. This reaction provides a rapid, mild, modular, and stereoselective (up to >20:1) entry to saturated O-heterocycles via nucleophilic trapping of an in situ-formed oxocarbenium intermediate. The key to overriding the carbonyl's innate somophilicity was found to be promoting the formation of organocobalt species and suppressing the radical exchange.
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Effervescence-assisted microextraction (EAM) is a novel sample pretreatment method based on the reaction of CO2 and H+ donors to generate CO2 bubbles and promote rapid dispersion of the extractant. During this process, the unique dispersion method increases the contact area between the target molecule and the extraction solvent, and the adsorption/extraction efficiency of the adsorbent/extractant toward the target molecule is also enhanced. The EAM technique is of particular interest due its convenient application, low running costs, reduced solvent consumption, high extraction efficiency, and environmental friendliness. Benefiting from the rapid development of extractants, the evolution and application of the EAM technology is becoming more tuned and diversified. Indeed, the synthesis of new extractants, such as nanomaterials with multi-pore structures, large specific surface areas, and rich active sites, has attracted extensive attention, as has the development of ionic liquids with strong extraction abilities and high selectivities. As a result, the EAM technology has been widely applied to the pretreatment of target compounds in various samples, such as food, plant, biological, and environmental samples. However, since these samples often contain polysaccharides, peptides, proteins, inorganic salts, and other interfering substrates, it is necessary to remove some of these substances prior to extraction by EAM. This is commonly achieved using methods such as vortexing, centrifugation, and dilution, among others. The treated samples can then be extracted using the EAM method prior to detection using high performance liquid chromatography (HPLC), gas chromatography (GC), and atomic absorption spectroscopy (AAS) to detect substances such as heavy metal ions, pesticide residues, endocrine-disrupting compounds (EDCs), and antibiotics. Using effervescence as a novel assisted method for the dispersion of solvents or adsorbents, the concentrations of Pb2+, Cd2+, Ni2+, Cu2+, bisphenol, estrogen, and the pyrethyl pesticides have previously been successfully determined. Moreover, many influencing factors have been evaluated during method development, including the composition of the effervescent tablet, the solution pH, the extraction temperature, the type and mass/volume of extractant, the type of eluent, the eluent concentration, the elution time, and the regeneration performance. Generally, the cumbersome single factor optimization and multi-factor optimization methods are also required to determine the optimal experimental conditions. Following determination of the optimal experimental conditions, the EAM method was validated by a series of experimental parameters including the linear range, the correlation coefficient (R2), the enrichment factor (EF), the limit of detection (LOD), and the limit of quantification (LOQ). In addition, the use of this method has been demonstrated in actual sample testing, and the obtained results have compared with those achieved using similar detection systems and methods to ultimately determine the accuracy, feasibility, and superiority of the developed method. In this paper, the construction of an EAM method based on nanomaterials, ionic liquids, and other emerging extractants is reviewed, wherein the preparation method, application range, and comparison of similar extractants were evaluated for the same extraction system. In addition, the current state-of-the-art in relation to EAM research and application when combined with HPLC, cold flame AAS, and other analytical techniques is summarized in terms of the detection of harmful substances in complex matrices. More specifically, the samples evaluated herein include dairy products, honey, beverages, surface water, vegetables, blood, urine, liver, and complex botanicals. Furthermore, issues related to the application of this technology are analyzed, and its future development trend in the field of microextraction is forecasted. Finally, the application prospects of EAM in the analysis of various pollutants and components are proposed to provide reference for monitoring pollutants in food, environmental, and biological samples.
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Polysaccharides are organic compounds widely distributed in nature, but structural order and disorder remain a formidable problem. In this study, based on the theoretical framework of the "relative ordered structure of polysaccharide" proposed in our previous work, the structural order of Hericium erinaceus polysaccharides from different regions was evaluated by FT-IR, methylation analysis, and 1H NMR spectroscopy combined with chemometric methods. The results of principal component analysis and heatmap cluster analysis revealed that 18-subfractions exhibit four different structural types with representative glycoside linkage types: fucogalactoglucan, glucofucogalactan, fucoglucan, and glucan. The main chain of heteroglucans often consists of ß-(1 â 6)-Glcp, ß-(1 â 4)-Glcp, and ß-(1 â 3)-Glcp residues, which are predominantly substituted at the O-3 and O-6 positions. The main chain structure of heterogalactans is α-(1 â 6)-Galp residues, which may be replaced by Fucp and Galp residues at O-2. Overall, our findings demonstrate the validity of the "relative ordered structure of polysaccharide" in Hericium erectus polysaccharides and simplify the complexity of polysaccharide structures.
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Hericium , Polissacarídeos , Espectroscopia de Infravermelho com Transformada de Fourier , Peso Molecular , Polissacarídeos/químicaRESUMO
A series of mononuclear gold(I) acetylide complexes with urea moiety, R'(3)PAuC≡CC(6)H(4)-4-NHC(O)NHC(6)H(4)-4-R (R' = cyclohexyl, R = NO(2) (2a), CF(3) (2b), Cl (2c), H (2d), CH(3) (2e), (t)Bu (2f), OCH(3) (2g); R' = phenyl, R = NO(2) (3a), OCH(3) (3b); R' = 4-methoxyphenyl, R = H (4a), OCH(3) (4b)), have been synthesized and characterized. The crystal structures of Ph(3)PAuC≡CC(6)H(4)-4-NHC(O)NHC(6)H(4)-4-NO(2) (3a) and (4-CH(3)OC(6)H(4))(3)PAuC≡CC(6)H(4)-4-NHC(O)NHC(6)H(5) (4a) have been determined by X-ray diffraction. Complexes 2a-2g, 3b, and 4a-4b show intense luminescence both in the solid state and in degassed THF solution at 298 K. Anion binding properties of complexes 2a-2g, 3a-3b, and 4a-4b have been studied by UV-vis and (1)H NMR titration experiments. In general, the log K values of 2a-2g with the same anion in THF depend on the substituent R on the acetylide ligand of 2a-2g: R = NO(2) (2a) > CF(3) (2b) ≥ Cl (2c) > H (2d) > CH(3) (2e) ≈ (t)Bu (2f) ≥ OCH(3) (2g). Complex 2a with NO(2) group shows the dramatic color change toward F(-) in DMSO, which provides an access of naked eye detection of F(-).
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Técnicas de Química Analítica/instrumentação , Técnicas de Química Sintética , Ouro/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Ureia/química , Cristalografia por Raios X , Dimetil Sulfóxido/químicaRESUMO
Infrared detection technology has been widely applied in many areas. Unlike internal photoemission and the photoelectric mechanism, which are limited by the interface barrier height and material bandgap, the research of the hot carrier effect from nanometer thickness of metal could surpass the capability of silicon-based Schottky devices to detect mid-infrared and even far-infrared. In this work, we investigate the effects of physical characteristics of Cr nanometal surfaces and metal/silicon interfaces on hot carrier optical detection. Based on the results of scanning electron microscopy, atomic force microscopy, and X-ray diffraction analysis, the hot carrier effect and the variation of optical response intensity are found to depend highly on the physical properties of metal surfaces, such as surface coverage, metal thickness, and internal stress. Since the contact layer formed by Cr and Si is the main role of infrared light detection in the experiment, the higher the metal coverage, the higher the optical response. Additionally, a thicker metal surface makes the hot carriers take a longer time to convert into current signals after generation, leading to signal degradation due to the short lifetime of the hot carriers. Furthermore, the film with the best hot carrier effect induced in the Cr/Si structure is able to detect an infrared signal up to 4.2 µm. Additionally, it has a 229 times improvement in the signal-to-noise ratio (SNR) for a single band compared with ones with less favorable conditions.