Infrared Microscopy Research Articles

Binding of tyrosine kinase inhibitor to epidermal growth factor receptor: surface-enhanced infrared absorption microscopy reveals subtle protein secondary structure variations.

Surface-Enhanced Infrared Absorption (SEIRA) has been proposed as a valuable tool for protein binding studies, but its performances have been often proven on model proteins undergoing severe secondary structure rearrangements, while ligand binding only marginally involves the protein backbone in the vast majority of the biologically relevant cases. In this study we demonstrate the potential of SEIRA microscopy for highlighting the very subtle secondary structure modifications associated with the binding of Lapatinib, a tyrosine kinase inhibitor (TKI), to epidermal growth factor receptor (EGFR), a well-known driver of tumorigenesis in pathological settings such as lung, breast and brain cancers. By boosting the performances of Mid-IR plasmonic devices based on nanoantennas cross-geometry, accustoming the protein purification protocols, carefully tuning the protein anchoring methodology and optimizing the data analysis, we were able to detect EGFR secondary structure modification associated with few amino acids. A nano-patterned platform with this kind of sensitivity bridges biophysical and structural characterization methods, thus opening new possibilities in studying of proteins of biomedical interest, particularly for drug-screening purposes.

Coupling between wetting dynamics, Marangoni vortices, and localized hot cells in drops of volatile binary solutions

HypothesisA sessile drop comprising a mixture of volatile solvents supports spatial variations in interfacial energy, which gives rise to solutal Marangoni flow, alongside evaporative loss of drop mass. Both the Marangoni flow and evaporation bring about a dance of concurrent and inter-connected phenomena: internal Marangoni vortices, localized hot cells, and complex wetting dynamics. ExperimentWe employ Particle Image Velocimetry and Infra-Red Microscopy to visualize Marangoni vortices, temperature variations, and the wetting dynamics of drops of toluene and ethanol mixtures. FindingsThe intensity of the measured phenomena vary concurrently in time and in like manner according with the initial composition of drops. In particular, we observe maximum intensity levels when the initial toluene proportion in the drops is 60%, and none of these phenomena in the case of pure toluene. Moreover, the drops initially expand on the solid in response to Marangoni flow, then contract due to evaporation; between these dynamic wetting regimes, we further observe a regime of one or periodic wetting/de-wetting cycles at low toluene concentrations. Our findings indicate that both the solutal Marangoni flow and evaporation drive the different phenomena we observe and confirm the connection between Marangoni vortices and the formation of localized hot cells.

The 1.1, 0.8 and 0.55–0.60 eV deep bands in detector-grade CdMnTe studied by photoluminescence spectroscopy

We present low-temperature photoluminescence (PL) spectra of Cd0·95Mn0·05Te grown by the Bridgman method. This is a promising material for nuclear detectors. We focus on three deep bands: 1.1, 0.8 and 0.55–0.60 eV. In order to achieve high resistivity in our crystals, essential in detector applications, we confirm the role of a deep intrinsic donor level at 0.8 eV, related to TeCd2+. It can pin the Fermi level in the mid-gap and increase the resistivity value. We suggest two interpretations of the 0.55–0.60 eV PL band origin. It can be connected with the deionization of a deep acceptor, such as Cd2−, or with simultaneous transitions of an electron (1.1 eV) and a hole (0.55–0.60 eV) followed by their recombination. These two energies together give the band gap value for Cd0·95Mn0·05Te at 5 K. The 1.1 eV luminescence in our crystals is related to Te secondary phases, the presence of which we confirm by infra-red microscopy. The correlation between the chemical composition of the crystals (changed by Cd- or Te-excess used in growth process and by post-growth annealing), the resistivity value and the PL results is shown.

Total Internal Reflection Peak Force Infrared Microscopy.

Total internal reflection (TIR) infrared spectroscopy is a convenient measurement tool for collecting spectra for chemical identification. However, TIR infrared microscopy lacks high spatial resolution due to the optical diffraction limit and difficulty to preserve a high-quality wave front for focus. In this article, we present the peak force infrared microscopy in the TIR geometry to achieve a 10 nm spatial resolution. Instead of optical detection, photothermal responses of the sample are collected in the peak force tapping mode of atomic force microscopy. We demonstrate the technique on two representative samples: structured polymers for soft matters and a hexagonal boron nitride flake for two-dimensional materials. As an extension of the apparatus, we also demonstrate nanoinfrared imaging with the TIR excitation for photoinduced force microscopy. The combination of TIR geometry with nanoinfrared microscopies simplifies the optical alignment, providing alternative instrument-designing principles for atomic force microscopy-based infrared microscopy.

Potentials and challenges of high-field PFG NMR diffusion studies with sorbates in nanoporous media

High magnetic fields (up to 17.6 T) in combination with large magnetic field gradients (up to 25 T/m) were successfully utilized in pulsed field gradient (PFG) NMR studies of gas and liquid diffusion in nanoporous materials. In this mini-review, we present selected examples of such studies demonstrating the ability of high field PFG NMR to gain unique insights and differentiate between various types of diffusion. These examples include identifying and explaining an anomalous relationship between molecular size and self-diffusivity of gases in a zeolitic imidazolate framework (ZIF), as well as revealing and explaining an influence of mixing different linkers in a ZIF on gas self-diffusion. Different types of normal and restricted self-diffusion were quantified in hybrid membranes formed by dispersing ZIF crystals in polymers. High field PFG NMR studies of such membranes allowed observing and explaining an influence of the ZIF crystal confinement in a polymer on intra-ZIF self-diffusion of gases. This technique also allowed measuring and understanding anomalous single-file diffusion (SFD) of mixed sorbates. Furthermore, the presented examples demonstrate a high potential of combining high field PFG NMR with single-crystal infrared microscopy (IRM) for obtaining greater physical insights into the studied diffusion processes.

Quantum imaging for the semiconductor industry

Infrared (IR) imaging is one of the significant tools for the quality control measurements of fabricated samples. Standard IR imaging techniques use direct measurements, where light sources and detectors operate in the IR range. Due to the limited choices of IR light sources or detectors, challenges in reaching specific IR wavelengths may arise. In our work, we perform indirect IR microscopy based on the quantum imaging technique. This method allows us to probe the sample with IR light, while the detection is shifted into the visible or near-IR range. Thus, we demonstrate IR quantum imaging of the silicon chips at different magnifications, wherein a sample is probed at a 1550 nm wavelength, but the detection is performed at 810 nm. We also analyze the possible measurement conditions of the technique and estimate the time needed to perform quality control checks of samples.

Current status of microplastics pollution in tianjin coastal waters

Microplastics (MPs) have home a global concern as well as climate change, ozone separation and ocean discrimination. In order to restore the distribution characteristics and influence factors of MPs in Tianjin coastal waters, the distribution of MPs in three sections of Tianjin office area was studied by using surface sampling, density usage separation and alternative microscopies. The size, shape and chemical composition of MPs were further analyzed. Our results show that the extent of MPs in the sea water samples were rang from 210 to 1170 particles . m−3 with a mean of 612 particles . m−3 in the three sections of the offshore area. Three shape types of MPs were present in the seawater samples, including slender fibers, irregular fragments and thin films. Fibers and fragments were predominant forms, which accounted for 52.1% and 46.8%, respectively. The particle size of the detected MPs was consistent with those reported by previous studies. The smaller the particle size, higher the content 55.3% MPs had particle size of less than 0.5mm. According to the microscopy analysis result, most of MPs in surface seawater samples showed a deep color (such as blue, black and red), and a few MPs showed colors of yellow, green and while. The main chemical components of MPs were analyzed by using infrared microscopy components were detected, including PP-PE, ABS, CE, EP, PA, PE, PET, PP, and PVC, with an order of PET >PP-PE >EP >CE >ABS >PE >PA >PVC >PP. The results demonstrated that the MPs pollution in the Tianjin offshore area was affected by the development of marine industries, such as marine fishery, port transportation, etc. In addition, the MPs pollution in the ocean was also affected by land-based sewage discharge due to the fact that Tianjin was an industrialized city with a large population density.

Study on the properties of GNPs/PS and GNPs/ODA composites incorporated SBS modified asphalt after short-term and long-term aging

In this study, polystyrene (PS) and octadecylamine (ODA) were grafted onto the graphene nanoplatelets (GNPs), to obtain GNPs/PS and GNPs/ODA which were then composited with styrene butadiene styrene (SBS) to prepare GNPs/ODA-SBS and GNPs/PS-SBS incorporated modified asphalts. The performance, aging process and chemical aspects of different modified asphalts were analyzed via three major indexes (ductility, penetration, and softening point), dynamic shear rheometer (DSR), Fourier transform infra-red (FT-IR) spectroscopy and fluorescence microscopy (FM) tests. Test results illustrated that softening point of the aged asphalt is reduced while the ductility increased slightly. Compared with their original state, softening point of the 0.08% GNPs/ODA-SBS modified asphalt decreased by about 9.32% after aging, while 0.04% GNPs/PS-SBS modified asphalt exhibited maximum increase in aging (decreased by 9.8%). Furthermore, the aged asphalt with modified GNPs (mGNPs) added exhibited improved viscoelastic properties and high temperature stability as compared to the pure aged SBS modified asphalt. This phenomenon was attributed to the inhibition of oxidation reaction during the aging process of mGNPs in the SBS modified asphalt, and hence can be deemed of great potential for practical applications and long-term storage of asphalt.

Resolution Enhancement in Wide-Field IR Imaging and Time-Domain Spectroscopy Using Dielectric Microspheres.

Wide-field imaging through dielectric microspheres has emerged in recent years as a simple and effective approach for generating super-resolution images at visible wavelengths. We present, to our knowledge, the first demonstration that dielectric microspheres can be used in a wide-field infrared (IR) microscope to enhance the far field resolution. We have observed a substantial improvement in resolution and magnification when images are collected through polystyrene microspheres. In addition, we demonstrate that spectroscopic imaging with a pulse-shaper based femtosecond mid-IR laser system is possible through the dielectric microspheres, which is a promising first step toward applying this technique to ultrafast IR imaging methods such as pump-probe and 2DIR microscopy.

Simultaneous Optical Photothermal Infrared (O-PTIR) and Raman Spectroscopy of Submicrometer Atmospheric Particles.

Physicochemical analysis of individual atmospheric aerosols at the most abundant sizes in the atmosphere (<1 μm) is analytically challenging, as hundreds to thousands of species are often present in femtoliter volumes. Vibrational spectroscopies, such as infrared (IR) and Raman, have great potential for probing functional groups in single particles at ambient pressure and temperature. However, the diffraction limit of IR radiation limits traditional IR microscopy to particles > ∼10 μm, which have less relevance to aerosol health and climate impacts. Optical photothermal infrared (O-PTIR) spectroscopy is a contactless method that circumvents diffraction limitations by using changes in the scattering intensity of a continuous wave visible laser (532 nm) to detect the photothermal expansion when a vibrational mode is excited by a tunable IR laser (QCL: 800-1800 cm-1 or OPO: 2600-3600 cm-1). Herein, we simultaneously collect O-PTIR spectra with Raman spectra at a single point for individual particles with aerodynamic diameters <400 nm (prior to impaction and spreading) at ambient temperature and pressure, by also collecting the inelastically scattered visible photons for Raman spectra. O-PTIR and Raman spectra were collected for submicrometer particles with different substrates, particle chemical compositions, and morphologies (i.e., core-shell), as well as IR mapping with submicron spatial resolution. Initial O-PTIR analysis of ambient atmospheric particles identified both inorganic and organic modes in individual sub- and supermicrometer particles. The simultaneous IR and Raman microscopy with submicrometer spatial resolution described herein has considerable potential both in atmospheric chemistry and numerous others fields (e.g., materials and biological research).

Porous Layered Double Hydroxide/TiO2 Photocatalysts for the Photocatalytic Degradation of Orange II

Layered Double Hydroxide (LDH)/TiO2 nanocomposites with photocatalytic properties were synthesized by both impregnation and the direct coprecipitation of LDH matrices using a colloidal suspension of TiO2 nanoparticles. While the two methods led to an efficient TiO2 nanoparticle immobilization, the direct coprecipitation allowed us to tune the amount of immobilized TiO2 within the materials. The LDH/TiO2 nanocomposites obtained were deeply characterized by chemical analysis (ICP-AES), Powder X-ray diffraction (XRD), Fourier Transformed Infra-Red (FTIR), Thermogravimetric analysis (TGA), and High-Resolution Transmission Electron Microscopy (HRTEM). Clearly, the immobilization of TiO2 by direct coprecipitation promoted a modification of the textural properties and a net increase in the surface area. The crystallized TiO2 nanoparticles can be distinctly visualized by HRTEM at the surface of the layered material. Several parameters, such as the nature of the chemical composition of LDH (ZnAl and MgAl), the method of immobilization and the amount of TiO2, were shown to play a crucial role in the physicochemical and photocatalytic properties of the nanocomposites. The photocatalytic efficiency of the different LDH/TiO2 nanocomposites was investigated using the photodegradation of a model pollutant, the Orange II (OII), and was compared to a pure TiO2 colloidal solution. The degradation tests revealed that the nanocomposite obtained from MgAl LDH at a low MgAl LDH/TiO2 ratio was the most efficient for the photodegradation of OII leading to complete mineralization in 48 h.

Amalgamation And Characterization Of Chemical Element Pillared Absorbent Aluminium Phyllosilicate Clay Mineral

Chemical element -pillared mud was orchestrated utilizing Chemical element chloride as the forerunner. The pillared item was portrayed utilizing Atomic Absorption/Emission Spectrophotometer (AAS), X-beam diffraction (XRD), BET Nitrogen adsorption, Fourier Transform Infra-Red (FTIR) and Scanning Electron Microscopy (SEM). The outcomes uncovered that a noteworthy improvement was accomplished on the pillared item. A mesoporous material was gotten conversely with the old style microporous pillared structure. The portrayal showed an expansion in the basal separating (d001).The presentation of titania on the absorbent aluminium phyllosilicate (parent) expands the groups because of the nearness of more OH gatherings of the column, which is deciphered as an impact of pillaring. The reduction in power is because of the procedure of lack of hydration and dehydroxylation required during pillaring. The BET explicit surface region and micropore volume of the pillared earth are 68.40 m2/g and 9.0 × 10-3cm3/g. These basic outcomes introduced indicated that orchestrated Nigern mud minerals are ecoaccommodating and great heterogeneous impetuses/adsorbents for expulsion of mechanical toxins and the creation of fine synthetic substances.

Proteome Mediated Synthesis of Biocompatible Green Fluorescence Cerium Oxide Quantum Dots with Enhanced Antioxidant Activity

Biocompatibility of quantum dots make good candidature for in vivo and in vitro diagnostic applications. In this study biocompatible cerium oxide quantum dots (CeO2 QDs) were synthesized from proteome of Justicia adhatoda leaf using simple aqueous protocol. Synthesized cerium oxide nanoparticle possessed green colored fluorescence under UV light. Quantum yield of CeO2 QDs was found to be 31.13% and were stable for 3 month at 4 °C. The band gap was found to be 3.26 eV which was higher than the band gap of bulk material i.e., 3.19 eV. The concentration of synthesized CeO2 QDs was determined as 165.96 ppm. These quantum dots were also characterized using an UV-Vis spectroscopy, Fourier Transform Infra-red Spectroscopy (FT-IR) and Transmission Electron Microscopy (TEM) respectively. It displayed distinct absorbance peak at 380 nm under UV-Visible spectrum. TEM images showed monodispersity of 2–5 nm spherical shaped CeO2 QDs and higher degree of crystallinity was observed by the pattern of selected area electron diffraction. In FTIR, the stretching observed at 621.65 cm–1 is assigned to Ce-O which confirmed the CeO2QDs formation. In view of biocompability, synthesized CeO2QDs were also characterised in reference to cell toxicity. Generated CeO2QDs has not showed any toxicity to J774A.1, Raw 264.7 and 3T3 cell lines in vitro cell viability assay. Significant enhancement in antioxidant activity of synthesized cerium oxide nanoparticles was observed from bulk material. This process offers plenty of advantages such as simple protocol, mild environment operation, potential for large scale commercial production of biocompatible CeO2QD. These QDs might find potential applications in both in vitro and in vivo diagnostics.

Vibrational Spectroscopic Based Approach for Diagnosing Babesia bovis Infection.

Babesia bovis parasites present a serious and significant health concern for the beef and dairy industries in many parts of the world. Difficulties associated with the current diagnostic techniques include the following: they are prone to human error (microscopy) or expensive and time-consuming (polymerase chain reaction) to perform. Little is known about the biochemical changes in blood that are associated with Babesia infections. The discovery of new biomarkers will lead to improved diagnostic outcomes for the cattle industry. Vibrational spectroscopic technologies can record a chemical snapshot of the entire organism and the surrounding cell thereby providing a phenotype of the organism and the host infected cell. Here, we demonstrate the applicability of vibrational spectroscopic imaging techniques including Atomic Force Microscopy Infrared (AFM-IR) and confocal Raman microscopy to discover new biomarkers for B. bovis infections. Furthermore, we applied Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) to detect B. bovis in red blood cells (RBCs). Based on changes in the IR spectral bands, with ATR-FTIR in combination with Partial Least Squares-Discriminant Analysis we were able to discriminate infected samples from controls with a sensitivity and specificity of 92.0% and 91.7%, respectively, in less than 2 min, excluding sample extraction and preparation. The proposed method utilized a lysis approach to remove hemoglobin from the suspension of infected and uninfected cells, which significantly increased the sensitivity and specificity compared to measurements performed on intact infected red blood cells (intact infected RBC, 77.3% and 79.2%). This work represents a holistic spectroscopic study from the level of the single infected RBC using AFM-IR and confocal Raman to the detection of the parasite in a cell population using ATR-FTIR for a babesiosis diagnostic.

Synthesis and characterization of zinc and copper oxide nanoparticles and their antibacteria activity

Inorganic nano-metal oxides can be effective alternatives to drug resistant organic antibiotics due to their broad spectrum antimicrobial activity against pathogenic and mutagenic gram-negative and positive bacteria. In this study, zinc and copper oxides (ZnO and CuO) were synthesised using a wet chemical reduction method. The oxide nanoparticles were characterized using X-ray diffraction (XRD), UV–Vis spectrometer, Fourier Transformed Infra-red spectrometer and Transmission electron microscopy (TEM). The antibacterial activities of the nanoparticles were investigated against e. coli and s. aureus using disk diffusion and microdilution tests. The TEM micrographs showed that copper oxide nanoparticles assumed a nanorod shape of average length of 100 ​nm whiles zinc oxide nanoparticles were spherical of average diameter of 15 ​nm. The FTIR results showed that the nanoparticles were free of impurities and organic surfactants, which was confirmed by XRD. For the antibacteria tests, the minimum inhibition concentration (MIC) of CuO against e. coli and s. aureus were 1 ​mg/ml and 0.25 ​mg/ml respectively whiles it was 0.1 ​mg/ml for ZnO against s. aureus with ZnO producing no inhibition against e. coli. With the microdilution test, both nanoparticles exhibited activity against both bacterias at all varying concentrations. The results concluded that CuO had higher antibacteria activity compared to ZnO.

Economical way of processing activated carbon from Calotropis gigantea and its suitability for application in Lithium/Sodium ion batteries

In the present study, highly porous activated carbon has been processed by an economical way which can be suitable for Lithium/Sodium ion batteries. Activated carbon was produced from a wasteland biomass of Calotropis gigantea stem using bleaching powder (CaOCl2) as chemical activating agent, in the ratio of 0.5:1 and 1:1 of chemical and biomass at different activation temperatures of 400 °C, 600 °C and 900 °C in normal atmospheric conditions. Characterisations like X-Ray Diffraction (XRD), Fourier Transform Infra-Red Spectroscopy (FTIR), Raman Spectroscopy and Field Emission Scanning Electron Microscopy (FESEM), High-Resolution Transmission Electron Microscopy (HRTEM) were done to find its suitability in Lithium/Sodium (Li /Na) ion battery applications. Presence of graphitic structure is found from XRD analysis. Functional groups found from FTIR analysis are active adsorption sites. Raman spectroscopy ordered graphitic structure is prerequisite for electrochemical performance. The highly porous activated carbon surface observed from FESEM analysis is further confirmed to have both mesopores and also micropores with appropriate surface area, through BET surface area analysis. Highly porous activated carbon and crystalline graphitic structure confirmed from HRTEM analysis makes it useful as an anode material for Li /Na ion batteries.

Remediation of Pb (II) ions from Kagara gold mining effluent using cotton hull adsorbent

Fixed-bed column adsorption experiment was conducted to remove lead ions from Kagara mining wastewater using unmodified Cotton Hull Adsorbent (CHA). Analysis of the wastewater effluent revealed that it contains as high as 85 mg/L lead ions. The Fourier Transform Infra-red, Brauneur-Emmet-Teller and Scanning Electron Microscopy characterization of the CHA revealed the presence of O-H, CO, C = O, CO-H and CH2 functional groups, surface area of 139.8 m2/g and porous micrograph of the adsorbent. The column flow experiment indicated that the maximum adsorption capacity of the carbon is 27.65 mg/g. Analysis of the experimental data using dynamic adsorption models revealed that Thomas model had insignificant difference between the average values of the experimental and the model's data. More so, it revealed high correlation coefficient of 0.77 to 0.96 signifying that Thomas model fitted adequately to the experimental data. This study has revealed that Kagara mining effluent which predominantly contains Pb ions can be sufficiently treated with unmodified cotton hull adsorbent before discharging it to the ecosystem.

Synthesis of cesium, sodium and nitrogen derived titanates using the Pechini sol-gel method

Cesium and sodium titanates with the respective stoichiometries of CsxTi2-x/4□x/4O4 (x ≈ 0.7) and Na2Ti6O13 was synthesized by making use of the Pechini sol-gel method. Direct intercalation of hydrazine hydrate in cesium and sodium titanates proved unsuccessful with the direct intercalation of ammonium into cesium titanate achieved. The protonated form of cesium titanate was successfully intercalated with hydrazine hydrate. Findings of the structural properties of the various titanates obtained from X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, Fourier-Transform Infra-Red spectroscopy, Raman spectroscopy and transmission electron microscopy are presented.

Molecular Imprinted Polymer for Ethylmorphine with Methacrylic Acid and Acrylamide as Functional Monomer in Butanol Using Two Polymerization Method

Ethylmorphine is an opioid that has therapeutic effects as narcotic analgesic and antitussive, which has low levels and can be misused. Hence, it is crucial to monitor by analyze the levels of ethylmorphine in blood selectively. The preparation method that can be used to extract ethylmorphine from the sample is using molecular imprinting solid-phase extraction (MI-SPE) due to its sensitivity and selectivity. This study aims to compare the result of synthesis using two different polymerization methods, and also to examine the analytical performance and characteristics of imprinted polymers from two distinct functional monomers: methacrylic acid (MAA) and acrylamide (AM). The stages of this study include the determination of association constants, synthesis of polymer MI-SPE ethylmorphine using bulk and precipitation polymerization method, extracted template from the polymer, and determined the adsorption ability, capacity, and selectivity of the polymer. MI-SPE that has been made then characterized by using Fourier-Transform Infrared (FTIR) and Scanning Electron Microscope (SEM). The results showed that MIP with acrylamide (MIP-AM) as functional monomer and made by precipitation polymerization had better analytic performances than MIP that made by bulk polymerization, with affinity value 0.072 mg/g and homogeneity value -0.77. It is also selective toward ethylmorphine with imprinting factor value 27.43. In addition, the result of characterization using FTIR and SEM showed that MIP-AM 2, MIP-MAA 1, and MIP-MAA 2 might have a low degree of polymerization due to the presence of vinyl peaks, besides MIP-AM 2 and MIP-MAA 2 had smaller particle size than the NIP with an average value of 0,31 ± 0,21 mm and 0.28 ± 0.05 mm. Based on the result of this study, MIP-AM made by precipitation polymerization could be used to extract ethylmorphine on solid-phase extraction.

Efficiency of Different Acetylation Methods Applied to Cellulose Fibers Waste from Pulp and Paper Mill Sludge

ABSTRACT In this study, the viability of acetylation in cellulose fibers waste (CFW) from pulp and paper mill sludge was investigated in comparison to bleached cellulose fibers (BCF). Four acetylation methodologies were applied. The inorganic ash composition of the CFW was determined by Energy Dispersive X-ray Spectrometry (EDS). The Degree of substitution (DS) of the acetylated fibers and their characterization using Fourier Transformed Infrared (FT-IR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), and Scanning electronic microscopy (SEM) were carried out. Results showed that the different acetylation methods are not effective for the esterification of CFW largely due to a high mineral content in their composition. The acetylation promoted the removal of the inorganic content in the CFW resulting in low efficacy levels. In BCF, higher efficiency levels were achieved, varying according to the methods. The different acetylation methods showed an efficiency range from 0.02 to 1.76 depending on the type of fiber.