A novel ultra-low-volume regimen combining 1 L polyethylene glycol and linaclotide versus 2 L polyethylene glycol for colonoscopy cleansing in low-risk individuals: a randomized controlled trial.

BACKGROUND AND AIMS: The single dose of 2 L polyethylene glycol (PEG) has shown high cleaning efficacy and tolerability in low-risk patients. However, the dosage of this regimen is still challenging for many patients. We investigated the efficacy and tolerability of a novel ultra-low-volume regimen using 1 L PEG and linaclotide (1 L PEG+L) versus a single dose of 2 L PEG in low-risk patients. METHODS: In this prospective, randomized, observer-blinded, multicenter study, low-risk adult patients scheduled for colonoscopy were enrolled and randomized (1:1) to receive the 1 L PEG+L regimen or the 2 L PEG regimen. The primary outcome was the effectiveness of bowel cleansing according to the Boston Bowel Preparation Scale. Secondary outcomes included cecal intubation rate, cecal insertion time, withdrawal time, polyp detection rate and adenoma detection rate, tolerability, adverse events, and willingness to repeat bowel preparation. The full analysis set (FAS) and per-protocol set (PPS) were used for statistical analyses. RESULTS: A total of 548 patients comprised the FAS, and 522 patients comprised the PPS. Noninferiority on adequate bowel cleansing of 1 L PEG+L vs 2 L PEG was established both in FAS (90.5% vs 91.6%, P = .644) and PPS (90.3% vs 92.4%, P = .390). There were no significant differences regarding the total score and each segment scores of the Boston Bowel Preparation Scale, cecal intubation rate, cecal insertion time, withdrawal time, polyp detection rate, and adenoma detection rate (all, P > .05). However, patients in the 1 L PEG+L group reported less nausea (7.7% vs 17.1%, P < .01) and vomiting (4.0% vs 10.9%, P < .01) and had a higher willingness to repeat bowel preparation (95.2% vs 82.2%, P < .01). CONCLUSIONS: The regimen of 1 L PEG+L was not inferior to 2 L PEG on colon cleansing, with better tolerability and higher willingness to repeat the bowel preparation in a low-risk population. (Clinical trial registration number: ChiCTR2100053273.).

Preparation and properties of aflatoxins imprinted polymer grafted onto the surface of mesoporous silica SBA-15 functionalized with double bonds.

Mesoporous silica Santa Barbara-15 was functionalized by methacryloxypropyl trimethoxysilane. Taking this as the carrier material, a new mesoporous silica surface imprinted polymer was synthesized by using the C=C bond, functional monomer α-methacrylic acid, and crosslinker ethylene glycol dimethacrylate, which was used to extract aflatoxin from grain efficiently. It is different from the preparation of surface imprinted polymers which is physically wrapping carrier materials with polymer layers. The chemical grafting method makes the coating of the polymer layer more controllable. A new method for selective separation, enrichment, and determination of trace aflatoxin in grain was established by using the polymers as the filter of the solid-phase extraction column and high-performance liquid chromatography. The linear range of the method was 0.5-100 µg/kg, R2  = 0.9990-0.9993. The recovery of aflatoxin G2, G1, B2, and B1 was 98.9-119.7% and the relative standard deviation was 3.07-5.76%. By comparing the self-made column with the immunoaffinity column, it was found that the self-made column had better extraction performance for aflatoxins than the immunoaffinity column. It can be used for the analysis and detection of aflatoxins in cereal.

[Progress in application of Bletilla striata polysaccharide in novel drug delivery systems and biomaterials].

As the main active ingredient of the orchidaceous herb Bletilla striata, B. striata polysaccharide(BSP) has pharmacological activities such as promoting coagulation, anti-inflammation, anti-oxidation, promoting wound healing, anti-tumor, and immunomodulation, and is biodegradable and non-toxic. Additionally, it has the material properties of suspension thickening, film-forming adhesion, coating and solubilizing, targeting and slow releasing, effect-enhancing and toxicity-reducing, etc., playing the role of unification of medicines and excipients. Therefore, BSP has a wide application prospect in the fields of drug delivery system and trauma repair. This paper reviews the research progress of BSP application in new drug delivery systems and biomaterials based on the related li-terature in recent years, with the aim of providing reference for the further research and application of BSP.

Application of surface-imprinted polymers supported by hydroxyapatite in the extraction of zearalenone in various cereals.

Surface-imprinted polymers supported by hydroxyapatite (HAP@MIPs) were prepared using coumarin-3-carboxylic acid and naringenin as dummy template molecules of zearalenone (ZEA). HAP@MIPs were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, particle size distribution analysis, energy-dispersive X-ray spectroscopy, and X-ray diffraction. The adsorption performance was studied. The results showed that it could reach the adsorption equilibrium within 6 min. The adsorption amount could reach 6.77 µg mg-1, while the concentration was 20 µg mL-1. The self-made solid-phase extraction (SPE) columns were prepared with HAP@MIPs as sorbents for the separation and purification of ZEA in cereal samples. The method was established by high-performance liquid chromatography (HPLC). The recoveries were in the range of 70.09-101.88%; the relative standard deviation was 2.06-8.47%. Finally, millet, coix lachryma, and corn were placed under extreme conditions to produce ZEA. The method was used to extract and analyze ZEA in the above samples. The results showed that self-made SPE columns with HPLC could be used for the separation and enrichment of ZEA in real samples. Graphical abstract.

Combined biocompatible medium with molecularly imprinted polymers for determination of aflatoxins B1 in real sample.

A kind of molecularly imprinted polymers modified with biocompatible medium was prepared by suspension polymerization. The obtained hybrid materials were used as the adsorbents for the solid-phase extraction of aflatoxins B1 in real samples. A structural analog of the target, 6-methyl-4-phenylchroman-2-one was used as the pseudo-template, owing to their lower toxicity and cheaper price compared with aflatoxins B1; and methacrylic acid and glycidyl methacrylate were used as the co-monomers. Scanning electron microscopy and size distribution analysis were used to characterize the obtained polymers. The extraction parameters were optimized to achieve the desired extraction performance. The polymer solid-phase extraction coupled with high-performance liquid chromatography was successfully applied to determine aflatoxins B1 from soy sauce without the process of protein removal. Under the optimum extraction conditions, the detection results of aflatoxins B1 in lab-made column in soy sauce samples was carried out, with a recovery rate of 96%. The established method presented a linear range from 10 to 1000 ng/mL with the coefficient of determination of 0.9994 and the limit of detection of 0.05 ng/mL. Likewise, the inherent selectivity of lab-made column towards aflatoxins B1, Ochratoxin A, and Zearalenone was demonstrated.

An amino-functionalized zirconium-based metal-organic framework of type UiO-66-NH2 covered with a molecularly imprinted polymer as a sorbent for the extraction of aflatoxins AFB1, AFB2, AFG1 and AFG2 from grain.

A surface imprinted polymer of type UiO-66-NH2@MIP was prepared by combining molecular imprinted polymers (MIPs) and an amino-functionalized zirconium-based metal-organic framework. Quercetin is used as the virtual template, UiO-66-NH2 acts as the carrier to which the monomer acrylamide can be copolymerized. The material was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. It was used as a sorbent in a solid-phase extraction column. The extraction conditions were optimized. The adsorption capacities for aflatoxins AFB1, AFB2, AFG1 and AFG2 by this SPE and by the commercial SPE were compared. The method was successfully applied to quantify the aflatoxins in grain. Figures of merit include (a) good linearity (range from 0.20-45 µg·kg-1) with R2 (range from 0.9986-0.9994), (b) low detection limits (90-130 ng·kg-1), (c) acceptable reproducibility (1.0-5.9%; for n = 6), and (d) relatively satisfactory recovery rates (74.3-98.6%). The new sorbent has good selectivity and reusability. Graphical abstractUiO-66-NH2@MIPs were synthesized with modified UIO-66-NH2 as core and quercetin as pseudo template. A cartridge was prepared with the polymers as the sorbent, and its performance was compared with different commercial SPE cartridges.

Synthesis of cobalt-based magnetic nanoporous carbon core-shell molecularly imprinted polymers for the solid-phase extraction of phthalate plasticizers in edible oil.

In this work, cobalt magnetic nanoporous carbon (Co-MNPC) is employed as an alternative to intensively used Fe3O4 cores for the preparation of magnetic molecularly imprinted polymers (Co-MNPC@MIPs) for the first time. Co-MNPC was prepared by one-step carbonization of Zeolitic Imidazolate Framework-67 (ZIF-67). Compared with the traditional Fe3O4 core, Co-MNPC showed a high specific surface area and large pore volumes. The prepared adsorbents, which could be rapidly collected from a matrix by external magnetic field, were applied for solid-phase extraction of phthalate plasticizers in edible oil. Several requisite extraction parameters were optimized to achieve desired extraction performance. Under the optimum extraction conditions, Co-MNPC@MIPs displayed better performance than commercialized columns. An analysis method based on Co-MNPC@MIPs coupled with gas chromatography (GC) was established. The linear range was 1-150 µg mL-1, and the detection limit range was 0.010-0.025 µg mL-1. The spiked recovery rate of the five phthalate plasticizers was 81.6-102.2%, with a relative standard deviation of 3.25-12.02%. Finally, the proposed method showed good feasibility for phthalate plasticizer extraction from edible oil.

Solid-phase extraction of aflatoxins using a nanosorbent consisting of a magnetized nanoporous carbon core coated with a molecularly imprinted polymer.

A core consisting of nanoporous carbon (MNPC) and magnetized with Co3O4 was coated with a molecularly imprinted polymer (MIP) by atom transfer radical precipitation polymerization. Ethyl 3-coumarincarboxylate was used as a pseudo-template to give a MIP that has a fairly specific recognition capability for aflatoxins. Batch rebinding studies were carried out to determine the specific adsorption equilibrium and specific recognition. Extraction is achieved in a single step by mixing and vortexing the sample extract with the Co-MNPC@MIP. The loaded nanosorbent was then magnetically separated and eluted with acetonitrile/water (6/4, v/v). The aflatoxins were then quantified by HPLC. Under optimal conditions, the detection limits for aflatoxins typically are 0.05-0.07 ng mL-1, recoveries from spiked corn are found to be 75.1 to 99.4%, and relative standard deviations range from 1.7 to 5.1 (n = 6). Graphical abstract Poly(methacrylic acid) was imprinted with the pseudo-template ethyl 3-coumarincarboxylate by atom transfer radical precipitation polymerization on the surface of cobalt-derived magnetic nanoporous carbon (Co-MNPC). This nanosorbent was used for the magnetic solid phase extraction of aflatoxins, followed by HPLC analysis.

Synthesis of molecularly imprinted polymers by atom transfer radical polymerization for the solid-phase extraction of phthalate esters in edible oil.

Novel molecularly imprinted polymers of phthalate esters were prepared by atom transfer radical polymerization using methyl methacrylate as functional monomer, cyclohexanone as solvent, cuprous chloride as catalyst, 1-chlorine-1-ethyl benzene as initiator and 2,2-bipyridyl as cross-linker in the mixture of methanol and water (1:1, v/v). The effect of reaction conditions such as monomer ratio and template on the adsorption properties was investigated. The optimum condition was obtained by an orthogonal experiment. The obtained polymers were characterized using scanning electron microscopy. The binding property was studied with both static and dynamic methods. Results showed that the polymers exhibited excellent recognition capacity and outstanding selectivity for ten phthalate esters. Factors affecting the extraction efficiency of the molecularly imprinted solid-phase extraction were systematically investigated. An analytical method based on the molecularly imprinted coupled with gas chromatography and flame ionization detection was successfully developed for the simultaneous determination of ten phthalate esters from edible oil. The method detection limits were 0.10-0.25 µg/mL, and the recoveries of spiked samples were 82.5-101.4% with relative standard deviations of 1.24-5.37% (n = 6).

Strong and ultrafast stimulus-healable lignin-based composite elastomers with excellent adhesion properties.

With the increased environmental issues, advanced high-performance and multifunctional polymeric materials derived from biomass have tremendous attention due to the great potential to replace their traditional petroleum-based counterparts. In this work, a series of lignin graft copolymers, lignin-graft-poly(n-butyl acrylate-co-acrylic acid) (Lig-g-P(BA-co-AA)), were rationally prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization. These lignin-based copolymers demonstrate good thermal stability and tunable glass transition temperature (Tg) values. The mechanical performance, including tensile strength, extensibility, Young's modulus, and toughness can be facilely adjusted by the BA/AA feed ratio and lignin content during polymerization. Owing to the extraordinary photothermal conversion ability of lignin, the Lig-B550 copolymer, containing 11.8 wt% lignin content, shows excellent stimulus-healing behavior within 1 min with a 97.1 % healing efficiency under near-infrared (NIR) laser irradiation. Moreover, the Lig-g-P(BA-co-AA) copolymers exhibit remarkable adhesion property, broadening their potential applications in the adhesive area. This grafting strategy is versatile and efficient, conferring the resultant lignin-based composite elastomers with dramatically enhanced mechanical properties and unprecedented photothermal behavior, which can inspire the further development of strong lignin-based sustainable elastomers.

Preparation and selective recognition of a novel solid-phase microextraction fiber combined with molecularly imprinted polymers for the extraction of parabens in soy sample.

A prepared molecularly imprinted polymer with ethyl p-hydroxybenzoate as template molecule was applied for the first time to a homemade solid-phase microextraction fiber. The molecularly imprinted polymer-coated solid-phase microextraction fiber was characterized by scanning electron microscopy and thermogravimetric analysis. Various parameters were investigated, including extraction temperature, extraction time, and desorption time. Under the optimum extraction conditions, the molecularly imprinted polymer-coated solid-phase microextraction fiber exhibited higher selectivity with greater extraction capacity toward parabens compared with the nonimprinted polymer-coated solid-phase microextraction fiber and commercial fibers. The molecularly imprinted polymer-coated solid-phase microextraction fiber was tested using gas chromatography to determine parabens, including methyl p-hydroxybenzoate, ethyl p-hydroxybenzoate, and propyl p-hydroxybenzoate. The linear ranges were 0.01-10 µg/mL with a correlation coefficient above 0.9943. The detection limits (under signal-to-noise ratio of 3) were below 0.30 µg/L. The fiber was successfully applied to the simultaneous analysis of three parabens in spiked soy samples with satisfactory recoveries of 95.48, 97.86, and 92.17%, respectively. The relative standard deviations (n=6) were within 2.83-3.91%. The proposed molecularly imprinted polymer-coated solid-phase microextraction method is suitable for selective extraction and determination of trace parabens in food samples.

Application of magnetic hydroxyapatite surface-imprinted polymers in pretreatment for detection of zearalenone in cereal samples.

This study is about the combination of magnetic solid phase extraction (MSPE) and high performance liquid chromatography-fluorescence detector (HPLC-FLD) for the pre-concentration and determination of Zearalenone (ZEA) in grain sample extracts. The novel sorbent (Fe3O4-HAP@MIPs), for selective and intelligent extraction of ZEA, was synthesized by doping Fe3O4 into the fibrous structure of hydroxyapatite nanoparticle (Fe3O4-HAP) and subsequently wrapping with molecularly imprinted polymers. The characteristic and morphology of magnetic particles were studied by infrared spectroscopy, vibrating sample magnetometer and scanning electron microscopy. The maximum adsorption capacity was 2.89 µg/mg. It could reach the adsorption equilibrium within 5 min. The adsorption isotherm of ZEA by the Fe3O4-HAP@MIPs were simulated. The results showed that the extraction process of ZEA with the sorbent accorded with Langmuir isotherm. The important factors affecting the extraction efficiency include elution solvent, washing solvent and the volume of them. After a serious of experiments, the optimum conditions were as follows: the volume of elution solvent was 4 mL of methanol and the washing solvent was acetonitrile-water 2:8（v/v). The calibration curve for ZEA was linear in the range of 10.00-300.00 µg/kg. The limit of detection and limit of quantitative was 2.00 µg/kg and 6.65 µg/kg, respectively. This method could provide a good reusability of 8 times and enough recoveries at three spiked levels (3, 5 and 8 ng/mL) ranging between 61.97% and 95.15% with the relative standard deviations of 1.94%∼7.44%. These results demonstrated that Fe3O4-HAP@MIPs could be used for separation, concentration and detection of ZEA from real samples.

Preparation and evaluation of molecularly imprinted microspheres for solid-phase extraction of 1,4-hydroxybenzoic acid esters in soy.

Molecularly imprinted microspheres (MIMs) were prepared by precipitation polymerization for the binding and recognition of 1,4-hydroxybenzoic acid esters. Ethyl p-hydroxybenzoate (EtPHB) was used as the template molecule, methacrylic acid as the functional monomer, ethylene dimethacrylate as the linking agent. It was evaluated by solid-phase extraction column packed with MIMs combined with liquid chromatography to determine trace preservatives including benzoic acid, methyl p-hydroxybenzoate, EtPHB, propyl p-hydroxybenzoate in food products. A solid-phase extraction based on MIM procedure was used to isolate four additives from the food matrix before quantitative analysis. The Scatchard plot suggested that the template-polymer system had two-site binding behavior with the dissociation constants of 0.3577 and 3.952 mg/g, respectively. The rebinding test, based on the molecularly imprinted solid-phase extraction column technique, showed the recoveries of soy samples spiked with four additives within 88.4-110.6%, with the relative standard deviations of 1.97-3.82%. Finally, the method was successfully applied for the analysis of parabens in foodstuff without traditional pretreatment.

Salivary gland ultrasonography in primary Sjögren's syndrome from diagnosis to clinical stratification: a multicentre study.

BACKGROUND: To determine the diagnostic accuracy of major salivary gland ultrasonography (SGUS) in primary Sjögren's syndrome (pSS) using the novel Outcome Measures in Rheumatology Clinical Trials (OMERACT) scoring system in a large-scale multicentre study. METHODS: SGUS was conducted for 246 pSS patients, 140 control subjects with conditions other than SS and 27 healthy control subjects. The echostructure features from the parotid and submandibular glands on both sides were graded using the novel OMERACT scoring system. Receiver operating characteristic curves were used to describe the diagnostic accuracy of the scoring system for pSS. The associations between the SGUS and disease characteristics were analysed to evaluate the clinical value of SGUS for pSS. RESULTS: The US scores in the pSS group were significantly higher than those in the non-pSS group (p < 0.001). The level of diagnostic accuracy was comparable with the scores of all four glands (AUC=0.908) when only the parotid and submandibular glands on either side were scored (AUC=0.910, 0.904, respectively). The optimal cut-off value for the left (right) parotid gland and the left (right) submandibular gland was 4, with maximal sensitivity (75.6% and 77.2%, respectively) and specificity (91.6% and 92.2%, respectively). The pSS patients with positive SGUS results presented a longer disease duration, parotid enlargement, dental loss and higher levels of serological markers, such as anti-SSA, anti-SSB, positive RF, IgG and γ-globulin%. CONCLUSIONS: SGUS with the OMERACT scoring system yields high sensitivity and specificity, demonstrating high diagnostic feasibility for pSS. The SGUS may have implications for deciding disease severity and treatment efficacy.

Preparation and characterization of molecularly imprinted microspheres for dibutyl phthalate recognition in aqueous environment.

Molecularly imprinted microspheres (MIMs) were prepared by suspension polymerization for the binding and recognition of dibutyl phthalate (DBP). DBP was used as the template molecule, methacrylic acid as the functional monomer, ethylene dimethacrylate (EDMA) as the linking agent, PVA as the dispersing agent, and Span 60 as the surfactant. The MIMs were characterized with electron microscope scanning and rebinding experiments. The Scatchard plot revealed that the template-polymer system has a two-site binding behavior with dissociation constants of 4.05 and 0.515 mmol/L. The MIMs exhibited the highest selective rebinding to DBP at 736.85 µg/g. The recoveries of the MIM-SPE column for DBP extraction was 94.75-101.9% with the RSD of 1.5-7.3%, indicating the feasibility of the prepared MIMs for DBP extraction. Finally, the method developed was used to analyze the trace levels of phthalate in aqueous environment samples.

Synthesis and application of magnetic-surfaced pseudo molecularly imprinted polymers for zearalenone pretreatment in cereal samples.

Zearalenone (ZEA) is a fungal contaminant widely found in grains. In cereal samples, trace zearalenone was extracted and enriched using magnetic-surfaced pseudo molecularly imprinted polymers (SPMIPs) and detected. SPMIPs were prepared with Fe3O4 as the magnetic core, modified halloysites nanotubes as supporting materials, and selective imprinted polymers as shells. Vinyl was modified on the surface of halloysites nanotube. SPMIPs were synthesized with pseudo templates. SPMIPs as the adsorbent of dispersed-solid phase extraction (µ-SPE) were used to purify and enrich ZEA from maize samples. After optimized, the pretreatment method was evaluated. The linearity of the method was ranged within 10-200 ng mL-1. LOD and LOQ were 2.5 ng mL-1 and 8 ng mL-1 respectively. The ZEA spiking recoveries in maize samples ranged within 74.95-88.41% were with good RSDs lower than 4.25%. The developed method was successful applied in maize, oat, and wheat sample treatments and compared.

Preparation of dummy molecularly imprinted polymers for extraction of Zearalenone in grain samples.

Surface molecularly imprinted polymers (MIL-101@MIPs) were prepared using MIL-101 as supporting core, imprinted polymers as selective shell synthesized with coumarin-3-carboxylic acid as dummy template of Zearalenone (ZEN), methacrylic acid as functional monomer, and ethylene glycol dimethacrylate hydroxyethyl methacrylate as cross-linker. The polymers were characterized by scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and particle-size distribution analyses. MIL-101@MIPs were used as the sorbent to compose the self-made cartridge. The cartridge was used to purify and enrich ZEN from real samples. Under optimized SPE conditions, a self-made cartridge can be reused for at least seven cycles. Elution was monitored with a high-performance liquid chromatography-fluorescence detection system. The linearity of the method ranged within 6.25-250 ng kg-1. The limits of detection ranged within 2.09 - 4.16 ng kg-1, and the limits of quantification ranged within 6.25 -12.50 ng kg-1, respectively. The matrix effects of four real samples were discussed. The spiking recoveries of ZEN ranged within 81.70%-90.10% with relative standard deviations lower than 5.56%. The performance of the self-made cartridge and immunoaffinity column was compared by chromatography.

Recyclable aqueous two-phase system based on two pH-responsive copolymers and its application to porcine circovirus type 2 Cap protein purification.

Aqueous two-phase system (ATPS) has great potential in industrial applications of bio-separations and bio-reactions. However, its large-scale application is limited by recovery difficulty of phase systems. In this paper, a recyclable ATPS was prepared by two pH-responsive copolymers (PADB4.99 and PMDM7.08) and applied for purification of porcine circovirus type 2 Cap protein fermentation broth (PCV2 Cap protein). Phase separation mechanism was studied by using low-field nuclear magnetic resonance (LF-NMR). The results showed that relatively desirable ATPS were formed successfully when two copolymer concentrations were 4%-6% (w/w) with pH 7.5-8.6. The main parameters, such as copolymer concentration, temperature, pH, type and concentration of salts, were investigated. The results demonstrated that the best ATPS consisted of 4% (w/w) PADB4.99 and 6% (w/w) PMDM7.08, the optimal partition coefficient (K) and extraction recovery (ER) of PCV2 cap protein were 0.25 and 94.2% in the presence of 50 mM Li2SO4, 3.53 and 93.4% in the presence of 40 mM KCl, respectively, at 30 °C, pH 8.1. The maximum purity of PCV2 Cap protein was 88.4%. In addition, the two phase-forming copolymers could be recycled by adjusting solution pH to their isoelectric points (pI), with recoveries of over 97.5%.

Application of pseudo-template molecularly imprinted polymers by atom transfer radical polymerization to the solid-phase extraction of pyrethroids.

A polymer-based adsorption medium with molecular recognition ability for homologs of pyrethroids was prepared by atom transfer radical polymer iration using a fragment imprinting technique. Phenyl ether-biphenyl eutectic was utilized as a pseudo-template molecule, and the adsorption medium prepared was evaluated by solid-phase extraction and gas chromatography. Selectivity of the medium for pyrethroids was evaluated using it as solid phase extraction packing by Gas Chromatography. The results demonstrated that the absorption amount of bifenthrin, fenpropathrin, permethrin, cypermethrin, fenvalerate, Dursban and pentachloronitrobenzene for molecularly imprinted polymers were 2.32, 2.12, 2.18, 2.20, 2.30, 1.30 and 1.40mgg-1, respectively, while the non-imprinted polymers were 1.20, 1.13, 1.25, 1.05, 1.20, 1.23 and 1.32mgg-1, respectively. The rebinding test based on the molecularly imprinted solid phase extraction column technique showed the recoveries of honey sample spiked with seven insecticides within 88.5-106.2%, with relative standard deviations of 2.38-5.63%. Finally, the method was successfully applied to the analysis of pyrethroids in a honey sample.

Enhanced enzymatic digestibility of mixed wood sawdust by lignin modification with naphthol derivatives during dilute acid pretreatment.

Effects of the addition of 2-naphthol and 2-naphthol-7-sulfonate on the dilute acid pretreatment of mixed wood sawdust were investigated, respectively. Compared to 2-naphthol, 2-naphtnol-7-sulfonate was more effective to enhance delignification and facilitate the enzymatic hydrolysis. The 72 h hydrolysis yield was improved by 47.8% for 2-naphthol-7-sulfone, while only 9.1% was observed for 2-naphthol. The surface charges, enzyme adsorption, and cellulose accessibility of dilute acid pretreated substrates with or without naphthol derivatives were examined. The improved enzymatic hydrolysis by adding 2-naphthol-7-sulfonate was ascribed to the higher negative surface charges, the lower enzyme non-productive binding, and the higher cellulose accessibility of pretreated substrates. Additionally, the HSQC NMR and 31P NMR analysis were carried out on both decomposed lignins and residual bulk lignins. It indicated that the addition of the naphthol derivatives during pretreatment could suppress the lignin repolymerization, which further mitigated the inhibition of residual lignins on enzymatic hydrolysis.