Molecular Functional Groups Research Articles

Surrogate fuel formulation for oxygenated and hydrocarbon fuels by using the molecular structures and functional groups

A methodology of surrogate fuel formulation by directly using molecular structure and functional groups for both oxygenated and hydrocarbon fuels is proposed and investigated. The novelty of this method is to construct surrogate fuel mixtures by directly matching the molecular structure and the key functional groups instead of using the combustion property targets explicitly. This method is tested by using two different classes of fuels, biodiesel and jet fuel. For biodiesel, by using four functional groups such as CH3, CH2, CH2CHCH, and COOCH3, a surrogate mixture of methyl-9-decenoate, 1,4-hexadiene and n-dodecane is formulated to demonstrate the efficacy of this method by comparing the resulting gas phase combustion targets between the formulated surrogate and biodiesel. For jet fuels, five functional groups such as CH3, CH2, CH, C, and phenyl were used to construct the Princeton 1st and 2nd generation surrogate jet fuel mixtures. The simulated results are compared with the experimental data and the results predicted by other surrogate fuel formulation methods. The comparisons show that the present method can formulate surrogated mixtures of both oxygenated and hydrocarbon real fuels and reproduce the combustion characteristics. Therefore, this method can be used not only for biodiesel and jet fuels, but also for other alternative fuels.

Nanoscale petrographic and geochemical insights on the origin of the Palaeoproterozoic stromatolitic phosphorites from Aravalli Supergroup, India.

Stromatolites composed of apatite occur in post-Lomagundi-Jatuli successions (late Palaeoproterozoic) and suggest the emergence of novel types of biomineralization at that time. The microscopic and nanoscopic petrology of organic matter in stromatolitic phosphorites might provide insights into the suite of diagenetic processes that formed these types of stromatolites. Correlated geochemical micro-analyses of the organic matter could also yield molecular, elemental and isotopic compositions and thus insights into the role of specific micro-organisms among these communities. Here, we report on the occurrence of nanoscopic disseminated organic matter in the Palaeoproterozoic stromatolitic phosphorite from the Aravalli Supergroup of north-west India. Organic petrography by micro-Raman and Transmission Electron Microscopy demonstrates syngeneity of the organic matter. Total organic carbon contents of these stromatolitic phosphorite columns are between 0.05 and 3.0 wt% and have a large range of δ(13) Corg values with an average of -18.5‰ (1σ = 4.5‰). δ(15) N values of decarbonated rock powders are between -1.2 and +2.7‰. These isotopic compositions point to the important role of biological N2 -fixation and CO2 -fixation by the pentose phosphate pathway consistent with a population of cyanobacteria. Microscopic spheroidal grains of apatite (MSGA) occur in association with calcite microspar in microbial mats from stromatolite columns and with chert in the core of diagenetic apatite rosettes. Organic matter extracted from the stromatolitic phosphorites contains a range of molecular functional group (e.g. carboxylic acid, alcohol, and aliphatic hydrocarbons) as well as nitrile and nitro groups as determined from C- and N-XANES spectra. The presence of organic nitrogen was independently confirmed by a CN(-) peak detected by ToF-SIMS. Nanoscale petrography and geochemistry allow for a refinement of the formation model for the accretion and phototrophic growth of stromatolites. The original microbial biomass is inferred to have been dominated by cyanobacteria, which might be an important contributor of organic matter in shallow-marine phosphorites.

Parameter Interpretation and Reduction for a Unified Statistical Mechanical Surface Tension Model.

Surface properties of aqueous solutions are important for environments as diverse as atmospheric aerosols and biocellular membranes. Previously, we developed a surface tension model for both electrolyte and nonelectrolyte aqueous solutions across the entire solute concentration range (Wexler and Dutcher, J. Phys. Chem. Lett. 2013, 4, 1723-1726). The model differentiated between adsorption of solute molecules in the bulk and surface of solution using the statistical mechanics of multilayer sorption solution model of Dutcher et al. (J. Phys. Chem. A 2013, 117, 3198-3213). The parameters in the model had physicochemical interpretations, but remained largely empirical. In the current work, these parameters are related to solute molecular properties in aqueous solutions. For nonelectrolytes, sorption tendencies suggest a strong relation with molecular size and functional group spacing. For electrolytes, surface adsorption of ions follows ion surface-bulk partitioning calculations by Pegram and Record (J. Phys. Chem. B 2007, 111, 5411-5417).

A hydrogel bioink toolkit for mimicking native tissue biochemical and mechanical properties in bioprinted tissue constructs

Advancement of bioprinting technology is limited by the availability of materials that both facilitate bioprinting logistics as well as support cell viability and function by providing tissue-specific cues. Herein we describe a modular hyaluronic acid (HA) and gelatin-based hydrogel toolbox comprised of a 2-crosslinker, 2-stage polymerization technique, and the capability to provide tissue specific biochemically and mechanically accurate signals to cells within biofabricated tissue constructs. First, we prepared and characterized several tissue-derived decellularized extracellular matrix-based solutions, which contain complex combinations of growth factors, collagens, glycosaminoglycans, and elastin. These solutions can be incorporated into bioinks to provide the important biochemical cues of different tissue types. Second, we employed combinations of PEG-based crosslinkers with varying molecular weights, geometries (linear, 4-arm, and 8-arm), and functional groups to yield hydrogel bioinks that supported extrusion bioprinting and the capability to achieve final construct shear stiffness values ranging from approximately 100Pa to 20kPa. Lastly, we integrated these hydrogel bioinks with a 3-D bioprinting platform, and validated their use by bioprinting primary liver spheroids in a liver-specific bioink to create in vitro liver constructs with high cell viability and measurable functional albumin and urea output. This hydrogel bioink system has the potential to be a versatile tool for biofabrication of a wide range of tissue construct types. Statement of SignificanceBiochemical and mechanical factors both have important implications in guiding the behavior of cells in vivo, yet both realms are rarely considered together in the context of biofabrication in vitro tissue construct models. We describe a modular hydrogel system that (1) facilitates extrusion bioprinting of cell-laden hydrogels, (2) incorporates tissue-specific factors derived from decellularized tissue extracellular matrix, thus mimicking biochemical tissue profile, and (3) allows control over mechanical properties to mimic the tissue stiffness. We believe that employing this technology to attend to both the biochemical and mechanical profiles of tissues, will allow us to more accurately recapitulate the in vivo environment of tissues while creating functional 3-D in vitro tissue constructs that can be used as disease models, personalized medicine, and in vitro drug and toxicology screening systems.

Combining vibrational biomolecular spectroscopy with chemometric techniques for the study of response and sensitivity of molecular structures/functional groups mainly related to lipid biopolymer to various processing applications.

The objectives of this project were to (1) combine vibrational spectroscopy with chemometric multivariate techniques to determine the effect of processing applications on molecular structural changes of lipid biopolymer that mainly related to functional groups in green- and yellow-type Crop Development Centre (CDC) pea varieties [CDC strike (green-type) vs. CDC meadow (yellow-type)] that occurred during various processing applications; (2) relatively quantify the effect of processing applications on the antisymmetric CH3 ("CH3as") and CH2 ("CH2as") (ca. 2960 and 2923 cm(-1), respectively), symmetric CH3 ("CH3s") and CH2 ("CH2s") (ca. 2873 and 2954 cm(-1), respectively) functional groups and carbonyl C=O ester (ca. 1745 cm(-1)) spectral intensities as well as their ratios of antisymmetric CH3 to antisymmetric CH2 (ratio of CH3as to CH2as), ratios of symmetric CH3 to symmetric CH2 (ratio of CH3s to CH2s), and ratios of carbonyl C=O ester peak area to total CH peak area (ratio of C=O ester to CH); and (3) illustrate non-invasive techniques to detect the sensitivity of individual molecular functional group to the various processing applications in the recently developed different types of pea varieties. The hypothesis of this research was that processing applications modified the molecular structure profiles in the processed products as opposed to original unprocessed pea seeds. The results showed that the different processing methods had different impacts on lipid molecular functional groups. Different lipid functional groups had different sensitivity to various heat processing applications. These changes were detected by advanced molecular spectroscopy with chemometric techniques which may be highly related to lipid utilization and availability. The multivariate molecular spectral analyses, cluster analysis, and principal component analysis of original spectra (without spectral parameterization) are unable to fully distinguish the structural differences in the antisymmetric and symmetric CH3 and CH2 spectral region (ca. 3001-2799 cm(-1)) and carbonyl C=O ester band region (ca. 1771-1714 cm(-1)). This result indicated that the sensitivity to detect treatment difference by multivariate analysis of cluster analysis (CLA) and principal components analysis (PCA) might be lower compared with univariate molecular spectral analysis. In the future, other more sensitive techniques such as "discriminant analysis" could be considered for discriminating and classifying structural differences. Molecular spectroscopy can be used as non-invasive technique to study processing-induced structural changes that are related to lipid compound in legume seeds.

Molecularly imprinted calixarene fiber for solid-phase microextraction of four organophosphorous pesticides in fruits

Calixarene was used as a functional monomer to fabricate a molecularly imprinted polymer (MIP) by sol–gel technique for solid-phase microextraction (SPME) of parathion-methyl and its structural analogs. The MIP-coated fiber possessed excellent thermal and chemical stability as well as high extraction capacity. Its selectivity and possible recognition mechanism were investigated. The similarities in molecular shape and functional group play a key role in the selective recognition of the imprinted material. Any changes to the structure of the template would decrease the imprinting factor. A comparison of MIP-SPME was made with liquid–liquid extraction coupled with gas chromatography for the determination of organophosphorus pesticides (OPPs) in fruits. Much lower limits of detection and better recoveries were achieved by SPME in spiked apple and pineapple samples. The experiment demonstrates that the proposed method using the calixarene MIP fiber was more suitable for selective determination of trace OPPs in those fruit samples.

Toward 5 V Li-Ion Batteries: Quantum Chemical Calculation and Electrochemical Characterization of Sulfone-Based High-Voltage Electrolytes

In seeking new sulfone-based electrolytes to meet the demand of 5 V lithium-ion batteries, we have combined the theoretical quantum chemistry calculation and electrochemical characterization to explore several sulfone/cosolvent systems. Tetramethylene sulfone (TMS), dimethyl sulfite (DMS), and diethyl sulfite (DES) were used as solvents, and three kinds of lithium salts including LiBOB, LiTFSI, and LiPF6 were added into TMS/DMS [1:1, (v)] and TMS/DES [1:1, (v)] to form high-voltage electrolyte composites, respectively. All of these electrolytes display wide electrochemical windows of more than 5.4 V, with the high electrolyte conductivities being more than 3 mS/cm at room temperature. It is indicated that to achieve the best ionic conductivity in TMS/DMS cosolvent, the optimized concentrations of lithium salts LiBOB, LiTFSI, and LiPF6 were 0.8, 1, and 1 M, respectively. Furthermore, the vibrational changes of the molecular functional groups in the cosolvents were evaluated by Fourier transform infrared spectroscopy. It is found that lithium salts show strong interaction with the main functional sulfone groups and sulfonic acid ester group, thus playing a vital role in the enhancement of the ionic conductivity and electrochemical stability of the solvent system. These sulfone-based solvents with high electrochemical stability are expected to become a new generation of a high-voltage organic electrolytic liquid system for lithium-ion batteries.

Simultaneous Nano- and Microscale Control of Nanofibrous Microspheres Self-Assembled from Star-Shaped Polymers.

Star-shaped polymers with varying arm numbers and arm lengths are synthesized, and self-assembled into microspheres, which are either smooth or fibrous on the nanoscale, and either nonhollow, hollow, or spongy on the microscale. The molecular architecture and functional groups determine the structure on both length scales. This exciting mechanistic discovery guides simultaneous control of both the nano- and microfeatures of the microspheres.

Effect of different plasticisers on the mechanical and barrier properties of extruded cast PHBV films

PHAs are gaining interest as biobased and biodegradable thermoplastics as an alternative for conventional polymers. However applications still struggle with the high brittleness of these polymers. In this study PHBV was plasticised by different types and concentrations of plasticisers in order to improve flexibility and elongation. Thereby an evaluation of the effectiveness of the selected plasticisers, which differ in their molecular weight and functional groups, is enabled. Those are propylene glycol, glycerol, triethyl citrate, castor oil, epoxidised soybean oil and polyethylene glycol. The results of an increasing plasticiser concentration show a decreasing melting temperature, increasing crystallinity, a decreasing Young’s Modulus and tensile strength as well as an increasing elongation at break. The water vapour and oxygen permeability is increased by all plasticisers but to a different extent. Overall the effectiveness of triethyl citrate and polyethylene glycol in PHBV showed the most promising results within thermal, mechanical and permeative characterisation.

Purification, characterization and anti-aging capacity of mycelia zinc polysaccharide by Lentinus edodes SD-08.

BackgroundIn the modern society, aging had been a major problem. People may rely on many medicines to delay it. However, lots of medicines were chemosynthetic, and they would do a bad side-effect on human body. Microbial sources could be used as a potential means of producing natural antioxidants. Lentinus edodes, commercial obtained in daily life, had recently become more attractive in physiological research. Zinc was now considered as a major element in assuring the correct functioning of an organism and essential for maintaining coordination of the major homeostatic networks. To investigate the bioconversion of zinc and the physiological effects of their complex (MZPS), the present studies were processed.MethodsMycelia polysaccharides (MPS) and mycelia zinc polysaccharides (MZPS) of Lentinus edodes SD-08 were extracted by hot water leaching and purified by DEAE-52 cellulose anion-exchange column chromatography separately. The zinc content was determined by flame atomic absorption spectrometry. The evaluation of monosaccharide compositions and proportions used gas chromatogram. The analysis of molecular weight used HPGPC chromatogram. The typical structure of polysaccharide was evaluated by IR spectrum. The antioxidant activities in vitro measured through reducing power, the scavenging effects on hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. The anti-aging activities in vivo measured through the total antioxidant capacity (T-AOC), GSH peroxide (GSH-Px), superoxide dismutase (SOD) and the contents of malondialdehyde (MDA).ResultsMPS and MZPS of Lentinus edodes SD-08 were extracted and purified by DEAE-52 cellulose anion-exchange column chromatography separately, and four fractions (MPS-1, MPS-2, MZPS-1 and MZPS-2) were obtained. In addition, MPS composing of rhamnose, arabinose and mannose (molar proportion = 1.75:1.00:3.02) and MZPS containing rhamnose, arabinose, mannose and glucose (molar proportion = 7.19:2.26:1.00:8.39) were investigated by gas chromatography. Infrared spectrum analysis indicated that there were C-H, C=O and -CH2 bonds in MPS and MZPS. MPS also had the typical absorption of -NH3+, -NH2 and -COOH. Compared with MPS, MZPS showed in vitro positive rising of reducing power and certain scavenging effects on hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. MZPS were found to upregulate in vivo the anti-aging activities of total antioxidant capacity (T-AOC), GSH peroxide (GSH-Px), superoxide dismutase (SOD), and decrease the contents of malondialdehyde (MDA).ConclusionsMZPS effectively showed potential anti-aging activities in vivo and antioxidant activities in vitro, and the molecular constituents, chemical bonds and functional groups of MZPS were superior to MPS, suggesting that the MZPS of L. edodes SD-08 could be used as a potential natural antioxidant.

Development and in silico Evaluation of Large‐Scale Metabolite Identification Methods Using Functional Group Detection for Metabolomics

Large‐scale identification of metabolites is key to understanding metabolism at the systems level. Advances in metabolomics technologies, particularly ultra‐high resolution mass spectrometry enable rapid, comprehensive analysis of metabolites that is impractical to achieve by conventional methods. A significant barrier to meaningful data interpretation is the identification of metabolites including unknowns and the determination of their role(s) in metabolic networks. Chemoselective (CS) probes to tag metabolite functional groups combined with high mass accuracy provide additional structural constraints for metabolite identification and quantification. We have developed a novel algorithm that efficiently detects functional groups within existing metabolite databases such as KEGG Ligand and the Human Metabolome Database, allowing for combined molecular formula and functional group queries to aid in metabolite identification without a priori knowledge. Analysis of the isomeric compounds in both HMDB and KEGG demonstrated a high percentage of isomeric molecular formulae (43% and 28% respectively), indicating the necessity for techniques such as CS‐tagging. Furthermore, these databases have only moderate overlap in molecular formulae. Thus, it is prudent to use multiple databases in metabolite assignment, since each major metabolite database represents different portions of metabolism. In silico analysis of CS‐tagging strategies demonstrate that combined FT‐MS derived molecular formulae and CS‐tagging can uniquely identify up to 71% of KEGG and 37% of the combined KEGG/HMDB database compared with 41% and 17% respectively without adduct formation.

Effect of the molecular structure of nitrogen compounds on the pollutant formation in a bubbling fluidized-bed combustor

To investigate the effect of the molecular structure of nitrogen compounds on the CO and NO emissions from experiments conducted in a bench-scale BFBC (bubbling fluidized-bed combustor), feed materials are prepared by mixing the model compounds (including pyridine, pyrrole, quinolone, aniline, nitrobenzene, 1-naphthylamine, urea, and arginine) with activated carbon to keep the overall nitrogen content at 1.5 wt% because this value is near the median of nitrogen content range (0.5 – 2.5 wt%) in most coals. The “de-NO” ratios for the combustion of various nitrogen compounds within the freeboard have been studied. Effects of bed temperature and additional water on the pollution emissions were also investigated. Experimental results show that the major factors for CO and NO formation, from the combustion of model compounds, were the molecular structure and functional groups, respectively. NO emission and it conversion both increased at first and then decreased with increasing bed temperature. Aromatic compounds have the highest fuel nitrogen (fuel-N) conversion to NOx in the combustor chamber, followed by heterocyclic and amine compounds. CO and unburned char have significant effect on NO reduction in the freeboard. Controlling the additional moisture content in the feed material is a promising method for reducing NO emissions.

Identification, control strategies, and analytical approaches for the determination of potential genotoxic impurities in pharmaceuticals: a comprehensive review.

Potential genotoxic impurities in pharmaceuticals at trace levels are of increasing concern to both pharmaceutical industries and regulatory agencies due to their possibility for human carcinogenesis. Molecular functional groups that render starting materials and synthetic intermediates as reactive building blocks for small molecules may also be responsible for their genotoxicity. Determination of these genotoxic impurities at trace levels requires highly sensitive and selective analytical methodologies, which poses tremendous challenges on analytical communities in pharmaceutical research and development. Experimental guidance for the analytical determination of some important classes of genotoxic impurities is still unavailable in the literature. Therefore, the present review explores the structural alerts of commonly encountered potential genotoxic impurities, draft guidance of various regulatory authorities in order to control the level of impurities in drug substances and to assess their toxicity. This review also describes the analytical considerations for the determination of potential genotoxic impurities at trace levels and finally few case studies are also discussed for the determination of some important classes of potential genotoxic impurities. It is the authors' intention to provide a complete strategy that helps analytical scientists for the analysis of such potential genotoxic impurities in pharmaceuticals.

Carboxylate groups play a major role in antitumor activity of Ganoderma applanatum polysaccharide

In this paper, the structure difference between the polysaccharides isolated from fruit bodies (FGAP) and submerged fermentation system (SGAP) of Ganoderma applanatum was investigated by means of GPC, HPLC and IR, respectively. And their antitumor activities were evaluated against Sarcoma 180 in vivo. The results showed that FGAP and SGAP were typical polysaccharides with different molecular weights, monosaccharide components, and functional groups. Closely related to the distinct structures, FGAP exhibited a better antitumor activity than SGAP. Moreover, since FGAP contained carboxylate groups rather than SGAP, such groups were chemically introduced into SGAP (CSGAP) by carboxymethylation in order to identify their contribution to antitumor activity. The results demonstrated that the inhibition of CSGAP against Sarcoma 180 in vivo was significantly enhanced by comparison to the native SGAP and even higher than that of FGAP, suggesting that the carboxylate groups played a major role in antitumor activity of G. applanatum polysaccharide.

Optimization, Purification, Characterization, and Antioxidant Activity of Exopolysaccharide Produced by the Northern Tooth Mushroom, Climacodon septentrionalis (Basidiomycota).

The optimization, purification, and characterization of exopolysaccharide (EPS) from Climacodon septentrionalis were investigated. The results showed that the optimal incubation time was 8 days for EPS production by C. septentrionalis; maltose and soy extract were the best carbon and nitrogen sources, respectively. One kind of EPS fraction was purified; it had a molecular weight of about 3.4 × 10(5) Da and mainly comprised glucose (98%). The main structure of EPS is α-glucopyranose. In addition, the EPS showed good antioxidant properties in vitro. The thermal stability of EPS also was investigated, and the results suggest that to maintain its bioactivity the processing temperature of EPS should not be more than 200°C. The structural characteristics of EPS, such as molecular weight, functional groups, monosaccharide constituents, and configuration of the glycosidic bond give EPS great potential for application as a natural antioxidant material in health, food, and therapeutics.

Design of multi-functional linear polymers that capture and neutralize a toxic peptide: a comparison with cross-linked nanoparticles.

In this paper, a library of multi-functional linear poly-N-isopropylacrylamide (pNIPAm) polymers having a range of molecular weights and functional groups were synthesized and their interaction with the hemolytic peptide, melittin, was examined. The linear pNIPAm (LPs) containing both tert-butyl group and carboxylic acids bound with the peptide by a combination of hydrophobic and electrostatic interactions and neutralized its toxicity. The melittin binding capacity and affinity of each LP was quantified and further compared with cross-linked multi-functional nanogel particles (NPs) having same combination of functional groups. The binding capacity of the LPs (weight of captured melittin/weight of LP) was independent of their molecular weight and was three times higher than that of previously reported NPs. The binding constant depended on the molecular weight of the LPs, showing the highest value of 1.1 × 108 (M-1) for a ∼1000 mer linear polymer with 40% tert-butyl group and 20% carboxylic acid. Comparison of the interactions of the LPs and NPs suggested the importance of the flexibility of the polymer chain in order to achieve high binding capacity and affinity.

Phase Transformation of Coal at High Temperature

Anthracite and bitumite were processed respectively at 1400°C,1700°C, 2000°C, 2200°C, 2400°C and 2600°C,and their chemical composition,resistivity,microstructure, phase composition,and the internal migration of molecular functional group were tested and characterized. The results indicate that moisture, ash and volatile in coal have gradually shifted and lost with the elevation of heat treatment temperature, while the higher temperature, the quicker and completer phase change. Heat treatment can make the coal transform from approximately insulative phase to conductive phase,. Furthermore, as the temperature increases, the conductive phase transformation effect is better. The higher the heat treatment temperature of coal, the more amorphous carbon transforming into crystalline carbon completely, but the less types of phases .

Quantitative Assessment of Liver Steatosis on Tissue Section Using Infrared Spectroscopy

Quantitative Assessment of Liver Steatosis on Tissue Section Using Infrared Spectroscopy

Quantifying lubricant droplet spreading on a flat substrate using molecular dynamics

Understanding the physical behavior of polymer-based lubricants on the nanoscale is of critical importance to a myriad of engineering applications and devices. We have used molecular dynamics simulations to quantitatively evaluate the physical mechanisms underlying perfluoropolyether lubricant spreading on a solid substrate. We quantify the effect of molecular mass, molecule length, and lubricant and substrate functional end groups on lubricant spreading. The results show that lubricant functional end groups play a critical role in lubricant spreading on the nanoscale. Lubricant spreading increases with increasing molecule length for lubricant with functional end groups, but decreases with the increase in molecule length for lubricant without functional end groups. In the former case, the fraction of the lubricant chain that is functional is the primary driving factor for lubricant spreading, while in the latter case, the molecular mass is most important. For both lubricants with and without functional end groups, spreading is inhibited by molecule entanglement beyond a critical molecule length, and spreading becomes independent of lubricant functional end groups and molecular mass.

Fractionation of five technical lignins by selective extraction in green solvents and characterisation of isolated fractions

Lignins from softwood, hardwood, grass and wheat straw were fractionated by selective extraction at ambient temperature using green solvents like acetone/water solutions of 10, 30, 50, 70 and 90% (v/v) acetone and ethyl acetate. A comparison between the isolated fractions and unfractionated lignins was made in terms of extraction yield, lignin solubility factor, molecular weight distribution and functional group composition. Low molecular weight (LMW) lignin fractions with narrow dispersity are obtained by extraction with ethyl acetate and acetone–water solution containing 30% acetone, with yields depending on the type and the functional group content of lignins. A significant amount (56%) of the organosolv hardwood lignin with low molecular weight (Mw=1868g/mol) and low dispersity was isolated from ethyl acetate. Insoluble fractions with very high molecular weight (Mw between 10 and 17kg/mol) are obtained in low yield from acetone–water solutions with 50, 70 and 90% acetone. LMW lignins are in general less condensed and have lower aliphatic hydroxyl content than parent lignins while the HMW fractions have a higher content of condensed hydroxyls. Principal component analysis on the chemical composition of lignins and isolated fractions determined from 31P NMR data showed the high heterogeneity of the technical lignins. Partial least squares models based on FT-IR spectral data were developed to predict the functional group content determined by quantitative 31P NMR analysis of technical lignins and lignin fractions. This approach can be used to develop simple, rapid and accurate analytical tools to monitor and control the selective fractionation of lignin.