A comprehensive status update on modification of foley catheter to combat catheter-associated urinary tract infections and microbial biofilms.

Present-day healthcare employs several types of invasive devices, including urinary catheters, to improve medical wellness, the clinical outcome of disease, and the quality of patient life. Among urinary catheters, the Foley catheter is most commonly used in patients for bladder drainage and collection of urine. Although such devices are very useful for patients who cannot empty their bladder for various reasons, they also expose patients to catheter-associated urinary tract infections (CAUTIs). Catheter provides an ideal surface for bacterial colonization and biofilm formation, resulting in persistent bacterial infection and severe complications. Hence, rigorous efforts have been made to develop catheters that harbour antimicrobial and anti-fouling properties to resist colonization by bacterial pathogens. In this regard, catheter modification by surface functionalization, impregnation, blending, or coating with antibiotics, bioactive compounds, and nanoformulations have proved to be effective in controlling biofilm formation. This review attempts to illustrate the complications associated with indwelling Foley catheters, primarily focussing on challenges in fighting CAUTI, catheter colonization, and biofilm formation. In this review, we also collate scientific literature on catheter modification using antibiotics, plant bioactive components, bacteriophages, nanoparticles, and studies demonstrating their efficacy through in vitro and in vivo testing.

Kinetic and Thermodynamic Studies of Precious Metals Sorption on Impregnated Lewatit VP OC 1026 from Chloride Solutions.

Precious metals are used in many branches of industries. Due to their rarity and diminishing natural resources, more and more new methods are being sought to recover them from secondary sources, which can be electronic waste or spent car exhaust converters. This paper presents the research on the recovery of precious metals from chloride solutions using the Aliquat 336-impregnated Lewatit VP OC 1026 sorbent. The study used a warm impregnation method without toxic solvents, which is beneficial for the environment. The maximal sorption capacities obtained for model solutions in 0.1 M HCl were: 95.6 mg/g for gold, 38.2 mg/g for palladium, and 36.2 mg/g for platinum. There were studied: kinetics and thermodynamics of sorption, as well as amounts of the sorbent, effects of phase contact time and HCl concentration on the sorption of precious metals. Positive values of enthalpy change ΔH° validate that the process is endothermic. The research was also carried out on a real leaching solution obtained by digesting a spent catalytic converter, containing small amounts of platinum group metals. Desorption of precious metal ions was conducted using 1 M thiourea in 1 M hydrochloric acid. The obtained impregnated sorbent proved to be effective for sorption of Au(III), Pd(II), Pt(IV) ions.

A waste-to-wealth conversion of plastic bottles into effective carbon-based adsorbents for removal of tetracycline antibiotic from water.

Currently, plastic waste and antibiotic wastewater are two of the most critical environmental problems, calling for urgent measures to take. A waste-to-wealth strategy for the conversion of polyethylene terephthalate (PET) plastic bottles into value-added materials such as carbon composite is highly recommended to clean wastewater contaminated by antibiotics. Inspired by this idea, we develop a novel PET-AC-ZFO composite by incorporating PET plastic-derived KOH-activated carbon (AC) with ZnFe2O4 (ZFO) particles for adsorptive removal of tetracycline (TTC). PET-derived carbon (PET-C), KOH-activated PET-derived carbon (PET-AC), and PET-AC-ZFO were characterized using physicochemical analyses. Central composite design (CCD) was used to obtain a quadratic model by TTC concentration (K), adsorbent dosage (L), and pH (M). PET-AC-ZFO possessed micropores (d ≈ 2 nm) and exceptionally high surface area of 1110 m2 g-1. Nearly 90% TTC could be removed by PET-AC-ZFO composite. Bangham kinetic and Langmuir isotherm were two most fitted models. Theoretical maximum TTC adsorption capacity was 45.1 mg g-1. This study suggested the role of hydrogen bonds, pore-filling interactions, and π-π interactions as the main interactions of the adsorption process. Thus, a strategy for conversion of PET bottles into PET-AC-ZFO can contribute to both plastic recycling and antibiotic wastewater mitigation.

Novel adsorbent for malachite green from okra stalks waste: synthesis, kinetics and equilibrium studies.

In this study, malachite green (MG) removal was performed with activated carbon synthesized from okra stalks by microwave assisted chemical activation method. In the synthesis of activated carbon, the effects of gas in the microwave, activation, and impregnation rate were investigated. The synthesized activated carbon characterization was investigated using BET, FT-IR, and SEM analyses. The activated carbon surface area achieved was 759.453 m2 g-1. In addition, the surface area of activated carbon synthesized using the conventional method was17.766 m2 g-1. The effect of the initial solution concentration on MG adsorption was investigated. According to the kinetic and equilibrium data, it was found that the adsorption process best fitted the pseudo-second order kinetic model and the Langmuir isotherm. According to the equilibrium data, the maximum adsorption capacity (qmax) of the monolayer was 119.05 mg g-1. In addition, MG adsorption was investigated by the experimental design method. The adsorption capacity at the determined optimum conditions was 99.63 mg g-1. All results show that activated carbon synthesized from waste biomass by combining the conventional method with microwave-assisted impregnation is a cheap and environmentally friendly adsorbent.

The synthesis of activated carbon from waste biomass using the conventional activation method is quite common. Activated carbon synthesis studies have increased in recent years with microwave-assisted impregnation, which has been integrated into the conventional activation method. Using this new method, the synthesis of activated carbon from okra stalk waste was carried out for the first time in this study. In addition, with this novel adsorbent, malachite green was removed from the aqueous solutions for the first time.

Spherical Binderless 4A/5A Zeolite Assemblies: Synthesis, Characterization, and Adsorbent Applications.

Zeolite microspheres have been successfully applied in commercial-scale separators such as oxygen concentrators. However, further enhancement of their applications is hampered by the post-synthetic shaping process that formulates the zeolite powder into packing-sized spherical bodies with various binders leading to active site blockage and suboptimal performance. Herein, binderless zeolite microspheres with a tunable broad size range from 2 µm to 500 µm have been developed with high crystallinity, sphericity over 92%, monodispersity with a coefficient of variation (CV) less than 5%, and hierarchical pore architecture. Combining precursor impregnation and steam-assisted crystallization (SAC), mesoporous silica microspheres with a wide size range could be successfully transformed into zeolite. For preserved size and spherical morphology, a judicious selection of the synthesis conditions is crucial to ensure a pure phase, high crystallinity, and hierarchical architecture. For the sub-2-µm zeolite microsphere, low-temperature prolonged aging was important so as to suppress external zeolization that led to a large, single macroporous crystal. For the large 500 µm sphere, ultrasound pretreatment and vacuum impregnation were crucial and facilitated spatially uniform gel matrix dispersion and homogenous crystallization. The obtained zeolite 5A microspheres exhibited excellent air separation performance, while the 4A microspheres displayed ammonium removal capabilities. This work provides a general strategy to overcome the existing limitations in fabricating binder-free technical bodies of zeolites for various applications.

Novel TiO2-Supported Gold Nanoflowers for Efficient Photocatalytic NOx Abatement.

In this study, we pioneered the synthesis of nanoflower-shaped TiO2-supported Au photocatalysts and investigated their properties. Au nanoflowers (Au NFs) were prepared by a Na-citrate and hydroquinone-based preparation method, followed by wet impregnation of the derived Au NFs on the surface of TiO2 nanorods (TNR). A uniform and homogeneous distribution of Au NFs was observed in the TNR + NF(0.7) sample (lower Na-citrate concentration), while their distribution was heterogeneous in the TNR + NF(1.4) sample (higher Na-citrate concentration). The UV-Vis DR spectra revealed the size- and shape-dependent optical properties of the Au NFs, with the LSPR effect observed in the visible region. The solid-state EPR spectra showed the presence of Ti3+, oxygen vacancies and electron interactions with organic compounds on the catalyst surface. In the case of the TNR + NF(0.7) sample, high photocatalytic activity was observed in the H2-assisted reduction of NO2 to N2 at room temperature under visible-light illumination. In contrast, the TNR + NF(1.4) catalyst as well as the heat-treated samples showed no ability to reduce NO2 under visible light, indicating the presence of deformed Au NFs limiting the LSPR effect. These results emphasized the importance of the choice of synthesis method, as this could strongly influence the photocatalytic activity of the Au NFs.

Waste Biomass-Mediated Synthesis of TiO2/P, K-Containing Grapefruit Peel Biochar Composites with Enhanced Photocatalytic Activity.

In this study, TiO2/P, K-containing grapefruit peel biochar (TiO2/P, K-PC) composites were synthesized in situ biomimetically using grapefruit peel as the bio-template and carbon source and tetrabutyl titanate as the titanium source. This was achieved using the two-step rotary impregnation-calcination method. Adjusting the calcination temperature of the sample in an air atmosphere could regulate the mass ratio of TiO2 to carbon. The prepared samples were subjected to an analysis of their compositions, structures, morphologies, and properties. It demonstrated that the prepared samples were complexes of anatase TiO2 and P, K-containing carbon, with the presence of graphitic carbon. They possessed a unique morphological structure with abundant pores and a large surface area. The grapefruit peel powder played a crucial role in the induction and assembly of TiO2/P, K-PC composites. The sample PCT-400-550 had the best photocatalytic activity, with the degradation rate of RhB, MO, and MB dye solutions reaching more than 99% within 30 min, with satisfactory cyclic stability. The outstanding photocatalytic activity can be credited to its unique morphology and the efficient collaboration between TiO2 and P, K-containing biochar.

Changes in chemical components and hepatoprotective effect of red Panax notoginseng processed by aspartic acid impregnation treatment.

BACKGROUND: Red Panax notoginseng (RPN) is one of the major processed products of P. notoginseng (PN), with more effective biological activities. However, the traditional processing method of RPN has some disadvantages, such as low conversion rate of ginsenosides and long processing time. RESULTS: In this work, we developed a green, safe, and efficient approach for RPN processing by aspartic acid impregnation pretreatment. Our results showed that the optimized temperature, steaming time, and concentration of aspartic acid were 120 °C, 1 h, and 3% respectively. The original ginsenosides in PN treated by aspartic acid (Asp-PN) were completely converted to rare saponins at 120 °C within just 1 h. The concentration of the rare ginsenosides in Asp-PN was two times higher than that in untreated RPN. In addition, we examined the protective effect of RPN and Asp-PN on acetaminophen-induced liver injury in a mouse model. The results showed that Asp-PN has significantly more potent hepatoprotective action than the RPN. The hepatoprotection of Asp-PN in acetaminophen-induced hepatotoxicity may be due to its anti-oxidative stress, anti-apoptotic, and anti-inflammatory activities. CONCLUSION: These results indicated that aspartic acid impregnation pretreatment may provide an effective method to shorten the steaming time, improve the conversion rate of ginsenosides, and enhance hepatoprotective activity of RPN. © 2024 Society of Chemical Industry.

Vibrational spectroscopy characterization of impregnated activated carbon adsorption of H2S.

Activated carbon filters are used for the removal of hazardous gases from the air. This research applied vibrational spectroscopy methods, including Fourier-transform infrared spectroscopy and Raman spectroscopy to characterize hydrogen sulfide adsorption on impregnated carbon materials with metals having reactivity toward hydrogen sulfide. The Fourier-transform infrared spectroscopy results demonstrated the formation of a new chemical bond between the impregnating metals and the sulfur, indicated by the appearance of a new band at 618 cm-1. The Raman spectra results showed that for the copper-impregnated activated carbon with the highest hydrogen sulfide adsorption capacity, a new vibrational band at 475 cm-1 evolved, indicating a copper-sulfur bond. In addition, upshifts in the carbon D sub-bands were observed after efficient hydrogen sulfide adsorption, along with a larger area of the approximately 1500 cm-1 band. Therefore, Fourier-transform infrared spectroscopy and Raman spectroscopy combination can potentially indicate H2S adsorption on impregnated activated carbon filters.

Silver-decorated SrTiO3 nanoparticles for high-performance supercapacitors and effective remediation of hazardous pollutants.

SrTiO3/Ag nanocomposites were synthesized using a facile wet impregnation method, employing rigorous experimental techniques for comprehensive characterization. XRD, FTIR, UV, PL, FESEM, and HRTEM were meticulously utilized to elucidate their structural, functional, morphological, and optical properties. The electrochemical performance of the SrTiO3/Ag nanocomposite was rigorously assessed, revealing an impressive specific capacitance of 850 F/g at a current density of 1 A. Furthermore, the photocatalytic activity of the SrTiO3/Ag nanocomposite was rigorously examined using methylene blue (MB) dye, and the results were outstanding. After 120 min of UV irradiation, the nanocomposite exhibited an exceptional MB dye degradation efficiency exceeding 88%. The SrTiO3/Ag nanocomposite represents an exemplary catalyst in terms of efficiency, cost-effectiveness, environmental compatibility, and reusability. The electron and superoxide radicals play a chief role in the MB dye degradation process. The inclusion of Ag within the SrTiO3 matrix facilitated the formation of a conductive nano-network, ultimately resulting in superior capacitive and photocatalytic performance.

Low viscosity silicone with less shrinkage for brain slices.

Plastination consists of replacing lipid and water with a curable polymer. This technique has numerous advantages, of which the production of non-toxic, inert, highly durable, dry, and easy maintenance and storage specimens stand out. Like all anatomical techniques, plastination also has disadvantages, and one of them is tissue shrinkage. The feasibility of using low viscosity domestic silicone (0,1Pa.s at 20°C) to plastinate brain slices was examined. Twenty humans, 10 millimeters (mm) brain slices were impregnated, ten slices each with two polymers [10 with domestic low viscosity polymer - P1 and 10 slices with Biodur® (0,45-0,6Pa.s at 20°C) S10]. Shrinkage was accessed by volume and area measurements. Volume shrinkage was significantly less in the slices impregnated with low viscosity domestic polymer, demonstrating the feasibility to plastinate brain slices with domestic low viscosity silicone polymer.

Effects of impregnation sequence on the NH3-SCR activity and hydrothermal stability of a Ce-Nb/SnO2 catalyst.

Hydrothermal stability is crucial for the practical application of deNOx catalyst on diesel vehicles, for the selective catalytic reduction of NOx with NH3 (NH3-SCR). SnO2-based materials possess superior hydrothermal stability, which is attractive for the development of NH3-SCR catalyst. In this work, a series of Ce-Nb/SnO2 catalysts, with Ce and Nb loading on SnO2 support, were prepared by impregnation method. It was found that, the NH3-SCR activities and hydrothermal stabilities of the Ce-Nb/SnO2 catalysts significantly varied with the impregnation sequences, and the Ce-Nb(f)/SnO2 catalyst that firstly impregnated Nb and then impregnated Ce exhibited the best performance. The characterization results revealed that Ce-Nb(f)/SnO2 possessed appropriate acidity and redox capability. Furthermore, the strong synergistic effect between Nb and Sn species stabilized the structure and maintained the dispersion of acid sites. This study may provide a new understanding for the effect of impregnation sequence on activity and hydrothermal stability and a new environmental-friendly NH3-SCR catalyst with potential applications for NOx removal from diesel and hydrogen-fueled engines.

Development and evaluation of a vacuum impregnation system for enhancement of biochemical properties of food materials.

Vacuum impregnation is a novel methodology for adding various substances to porous foods. This study aimed to develop a cost effective automate system for vacuum impregnation of food materials to enhance their nutritional, functional and sensory properties depending on the functionality of the impregnation solution. The developed vacuum impregnation system includes a vacuum chamber, vacuum pump and an automation setup for creating and maintaining vacuum conditions, feeding impregnated solutions to the samples and releasing vacuum. Fresh-cut spinach leaves were impregnated with ascorbic acid (AsA) and calcium chloride (Cacl2) (10% concentration) in the setup in order to test the effect of the process on some biochemical properties. Statistical analysis revealed significant effect of vacuum impregnation on the biochemical properties (total soluble solids, total phenolic content, flavonoid content and free radical scavenging activity) and color of spinach leaves during storage up to 4 days. Impregnation process showed significant increase in the total phenolic and flavonoid content of the spinach leaves. Increment up to 78% in antioxidant activity was seen for the uncoated impregnated leaves as compared to 59% activity in untreated samples. Thus, products with desired parameters can be produced with this process with minimal impact on their properties at a lower cost and in a shorter time period.

Aerosol Spray Drying Guided Synthesis of Ultrasmall Alloyed Bimetallic Nanoparticles Supported on Silica for Catalytic Semihydrogenation.

Supported bimetallic nanoparticles (NPs) with ultrasmall sizes and homogeneous alloying are attractive for catalysis. However, facile synthesis of this type of material remains very challenging. Here, the aerosol drying impregnation method for rapid, scalable, and general synthesis of silica-supported bimetallic NPs is proposed. The method relies on aerosol spray drying to promote the mixing and dispersing of binary metal precursors on SiO2 . It is capable of controlling the composition and size of bimetallic NPs and avoids the use of expensive metal complex salts and complicated experiment procedures. Twelve permutations combining a noble metal (Pd, Ru, and Pt) and a base one (Fe, Co, Ni, and Cu) with ultrasmall sizes (1.4-2.2 nm in average size), uniform dispersion, and good alloying are synthesized. Interesting activity and selectivity trends in catalytic semihydrogenation of phenylacetylene over the supported Pd-based NPs can be observed. The silica-supported PdNi NPs deliver both high activity and styrene selectivity. Spectroscopic and density functional theory calculation results reveal the improved chemoselectivity originated from the suitably down-shifted d-band center of the PdNi NPs inducing an increased energy barrier for overhydrogenation and a weakened styrene adsorption.

Pseudomonas species may appear strikingly filamentous in tissue sections: an important consideration for surgical pathologists and a reminder of the utility of modified silver impregnation methods.

Although tissue culture is the gold standard for diagnosing infection, histologic examination of surgically resected tissue can be a critical component in the diagnosis of tissue infection. The goal of this brief report is to alert surgical pathologists that Pseudomonas species can appear strikingly filamentous histologically and may somewhat mimic the appearance of filamentous bacteria, such Actinomyces or Nocardia, or thin fungal hyphae. A secondary aim is to raise awareness that Pseudomonas can sometimes only be identified histologically through the use of a modified silver impregnation method (Steiner stain). Five cases of filamentous Pseudomonas were encountered in three different surgical pathology subspecialities (ophthalmic pathology, cardiovascular pathology, and dermatopathology) over a 1-year period. All cases were of formalin-fixed, paraffin-embedded tissue, stained using hematoxylin & eosin (H&E) and multiple histochemical stains. Four cases grew Pseudomonas aeruginosa in culture and, in the fifth case, a nonaeruginosa species was detected using polymerase chain reaction-based methods. The markedly filamentous-appearing Pseudomonas organisms were identified in five different tissue sites: vascular graft, enucleation (whole eye) specimen, scleral biopsy, soft-tissue excision, and skin punch biopsy. In one of the five cases the organisms were seen on H&E, and in only two of the five were the organisms seen on Brown-Hopps stain. In all five cases, the organisms were identified on Steiner stain. It is therefore important to recognize that Pseudomonas can appear markedly filamentous, Pseudomonas or other bacterial infection is suspected, the surgical pathologist would be advised to employ the Steiner stain to most consistently detect the organisms.

Bio-aerogels: Fabrication, properties and food applications.

Traditional inorganic aerogels sustainability, biodegradability, and environmental safety concerns have driven researchers to find their safe green alternatives. Recently, interest in the application of bio-aerogels has rapidly increased in the food industry due to their unique characteristics such as high specific surface area and porosity, ultralow density, tunable pore size and morphology, and superior properties (physicochemical, mechanical, and functional). Bio-aerogels, a special category of highly porous unique materials, fabricated by the sol-gel method followed by drying processes, comprising three-dimensional networks of interconnected biopolymers (e.g., polysaccharides and proteins) with numerous air-filled pores. The production of bio-aerogels begins with the formation of a homogeneously dispersed precursor solution, followed by gelation and wet gel drying procedures by employing special drying techniques including atmospheric-, freeze-, and supercritical drying. Due to their special properties, bio-aerogels have emerged as sustainable biomaterial for many industrial applications, i.e., encapsulation and controlled delivery, active packaging, heavy metals separation, water and air filtration, oleogels, and biosensors. Bio-aerogels are low-cost, biocompatible, and biodegradable sustainable material that can be used in improving the processing, storage, transportation, and bioavailability of food additives, functional ingredients, and bioactive substances for their health benefits with enhanced shelf-life.

Toward systematic understanding of adsorptive removal of legacy and emerging per-and polyfluoroalkyl substances (PFASs) by various activated carbons (ACs).

Per-and polyfluoroalkyl substances (PFASs) have received great attention due to their persistence, bioaccumulation and toxicity. Various activated carbons (ACs) exhibit wide variability in adsorptive performance towards PFASs. In order to gain a systematic understanding of adsorptive removal of legacy and emerging PFASs by ACs, the adsorption of ten PFASs on various ACs was comprehensively investigated. Results showed that granular activated carbon-1 (GAC-1) and powdered activated carbon-1 (PAC-1) removed more than 90% of all target PFASs. Particle size, surface charge, and micropores quantity of ACs were closely related to their performance for PFASs removal. Electrostatic interaction, hydrophobic interaction, surface complexation and hydrogen bonding were the adsorption mechanisms, with hydrophobic interaction being the predominant adsorptive force. Physical and chemical adsorption were both involved in PFAS adsorption. The removal rates of PFASs by GAC-1 decreased from 93%-100% to 15%-66% in the presence of 5 mg/L fulvic acid (FA). GAC was able to remove more PFASs under acidic medium, whereas PAC removed hydrophobic PFASs better under the neutral medium. The removal rates of PFASs by GAC-3 increased significantly from 0%-21% to 52%-97% after being impregnated with benzalkonium chlorides (BACs), demonstrating the superiority of this modification method. Overall, this study provided theoretical support for removing PFASs from water phase with ACs.

Retention of methyl iodide on metal and TEDA impregnated activated carbon using indigenously developed setup.

Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issue. In case of any nuclear accident, there is a great need to mitigate the radioactive organic iodide immediately as it accumulates in human bodies, causing severe consequences. Current research focuses on removing organic iodides, for which the surface of activated carbon (AC) was modified by impregnating it with different metals individually, i.e. Ag, Ni, Zn, Cu and with the novel combination of these four metals (AZNC). After the impregnation of metals, triethylenediamine (TEDA) was coated on metal impregnated activated carbon (IAC) surface. The adsorption capacity of the combination of four metals IAC was found to be 276 mg/g as the maximum for the trapping of CH3I. Whereas TEDA-metal impregnation on ACs enhanced the removal efficiency of CH3I up to 352 mg/g. After impregnation, adsorption capacity of AZNC and AZNCT is significantly higher as compared to AC. According to the finding, t5% of AZNCT IAC is 46 min, which is considerably higher than the t5% of other tested adsorbents. According to isotherm fitting data, Langmuir isotherm was found superior for describing CH3I sorption onto AC and IACs. Kinetics study shows that pseudo second order model represented the sorption of CH3I more accurately than the pseudo first order. Thermodynamic studies gave negative value of ΔG which shows that the reaction is spontaneous in nature. Based on the findings, AZNCT IAC appears to have a great potential for air purification applications in order to obtain clean environment.

Biochar-supported magnesium oxide as high-efficient lead adsorbent with economical use of magnesium precursor.

With unique porous structure inherited from lignocellulose, biochar was an appropriate carrier for small-size MgO materials, which could simplify the synthetic process and better solve agglomeration and separation problems during adsorption. Biochar-supported MgO was prepared with impregnation method. Under different synthesis conditions, the obtained MgO presented diverse properties, and moderate pyrolysis condition was conducive to the improvement of Mg conversion rate. The Pb(II) capacity was highly correlated with Mg content, rather than the specific surface area. Reducing the pyrolysis temperature or increasing the usage of supporter could improve adsorption efficiency when using Mg content-normalized capacity as the criterion. The better release ability of Mg, contribute by the higher extent of hydration and better spread of MgO, were the critical factors. The maximal Mg content-normalized capacity could reach 0.932 mmol·mmol-Mg-1 with the mass ratio of biochar/MgCl2·6H2O = 4:1 at the pyrolysis temperature of 600 °C. Considering the ultimate utilization efficiency of Mg in precursor, the optimum Mg consumption-normalized capacity was 0.744 mmol·mmol-Mg-1 with the mass ratio of biochar/MgCl2·6H2O = 1:1 at 600 °C.

Direct Observation of Atomistic Reaction Process between Pt Nanoparticles and TiO2 (110).

The catalytic activity and selectivity of heterogeneous catalysts are governed by atomic and electronic structures at the heterointerface between noble metal nanoparticles (NPs) and oxide substrates. In specific chemical reactions, it is well-known that the catalytic activity is strongly suppressed by annealing in a reducing atmosphere, so-called strong metal-support interaction (SMSI). However, it is still unclear the formation process and atomistic origin of the SMSI. By preparing well-defined platinum (Pt) NPs supported on atomically flat TiO2 (110) substrate, we directly show the formation of chemically ordered Pt-Ti intermetallic NPs and impregnation of NPs into TiO2 substrate at high temperatures by using atomic-resolution scanning transmission electron microscopy combined with electron energy-loss spectroscopy. Furthermore, we observed negative charge transfer from the Pt-Ti intermetallic NPs to the TiO2 surface, which would strongly affect the catalytic activities.