Preparation of surface molecularly imprinted polymer and its application for the selective extraction of teicoplanin from water

Study on the creation of boronate affinity-based oriented imprinted silica nanoparticles and their selective recognition toward glycopeptide antibiotics in food and water

Taking into account the drug resistance of antibiotics, teicoplanin has been banned in the veterinary field. Also, it brings threat to people's health when they eat foods containing teicoplanin residue. In addition, the abuse of teicoplanin in humans and food animals also poses a potential risk to water. Therefore, it is crucial to purify teicoplanin from food before quantifying its amount. In this study, researchers employed boronate affinity-based controlled oriented surface imprinting technique to produce molecularly imprinted polymers (MIPs) for the isolation of teicoplanin. The 3-fluoro-4-formylphenylboronic acid-functionalized silica nanoparticle substrate was first used as the supporting material for immobilizing teicoplanin. Next, the substrate surface was coated with an imprinting coating whose thickness could be controlled, produced through the self-copolymerization of dopamine and m-aminophenylboronic acid (APBA) in water. After the template was removed, 3D cavities that matched the template were created in the imprinting layer. The prepared teicoplanin-imprinted silica nanoparticles exhibited several significant satisfactory results such as good specificity, high binding capacity (46.9 ± 2.3 mg g-1), moderate binding constant ((5.46 ± 0.18) × 10-5 M-1), fast kinetics (8 min) and low binding pH (pH 5.0) toward teicoplanin. The teicoplanin-imprinted silica nanoparticles could still be reused after seven cycles of adsorption-desorption, which indicated a high chemical stability. In addition, recoveries of the proposed method for teicoplanin at three spiked levels in milk and water ranged from 91.8 to 105.6% and 92.3 to 97.4%, respectively. The teicoplanin-imprinted silica nanoparticles are capable of identifying the target teicoplanin in real samples in a simple, fast, selective and efficient manner.

A new strategy for RRS-based determination of phosphate with a bifunctional Fe3O4 magnetic nanoparticle surface molecularly imprinted polydopamine probe

In this paper, a magnetic nanoparticle surface molecularly imprinted polydopamine RRS probe Fe3O4@MIP was prepared using phosphomolybdic acid (PMo) as the template, Fe3O4 magnetic nanoparticles as the substrate and dopamine hydrochloride (PD) as the monomer and crosslinking agent for the determination of PO43-. Under acidic conditions, phosphomolybdic acid is formed by the reaction of PO43- with ammonium molybdate (MSA), which can be imprinted with the Fe3O4@MIP probe surface and reduced to phosphomolybdic blue (PMoB) by ascorbic acid (Aa). Strong resonance Rayleigh scattering energy transfer (RRS-ET) occurs between the probe and PMoB, resulting in a decrease in the RRS signal value. A new, simple and selective RRS method for the determination of PO43- in water samples was developed. The linear range of this method is 1-22.5 μmol L-1, and the detection limit (DL) is 0.49 μmol L-1. Furthermore, the magnetic enrichment ability of Fe3O4@MIP is discussed. Experimental data show that even 0.2 μmol L-1 of phosphate can be detected within a 20% error range.

Biomass waste-derived magnetic material coated with dual-dummy-template molecularly imprinted polymer for simultaneous extraction of organophosphorus and carbamate pesticides

An eco-friendly biomass waste-derived magnetic material coated with a dual-dummy-template molecularly imprinted polymer was fabricated using aqueous ethanol as a green porogen, lower amounts of toxic compounds as template molecules, and tyrosine and tryptophan as biocompatible binary monomers. The binding characteristics and selectivity of the material toward pesticides were assessed. High adsorption capacities ranging from 150.11 to 509.09 mg g-1 and imprinting factors reaching 2.2 were achieved within just 30 s. The material was applied for extraction of organophosphorus and carbamate pesticides prior to HPLC analysis. Under the optimum conditions, low limits of detection and quantitation were achieved, with ranges of 0.05-1.49 μg/L and 0.18-5.00 μg/L, respectively. The established approach enables efficient analysis of vegetable and fruit samples, yielding satisfactory recoveries ranging between 80 and 110 %. The method showed promise as an analytical method for the sensitive enrichment of pesticide residues in vegetable and fruit samples.

Molecularly Imprinted Polymers for Pharmaceutical Impurities: Design and Synthesis Methods

The safety of a medicinal product is determined by its pharmacological and toxicological profile, which depends not only on the active substance's toxicological properties, but also on the impurities it contains. Because impurities are a problem that must be considered to ensure the safety of a drug product, many studies have been conducted regarding the separation or purification of active pharmaceutical ingredients (APIs) and the determination of impurities in APIs and drug products. Several studies have applied molecularly imprinted polymers (MIPs) to separate impurities in active ingredients and as adsorbents in the sample preparation process. This review presents the design of MIPs and the methods used to synthesise MIPs to separate impurities in APIs and drug product samples, the application of MIPs to separate impurities, and a view of future studies involving MIPs to remove impurities from pharmaceutical products. Based on a comparison of the bulk and surface-imprinting polymerisation methods, the MIPs produced by the surface-imprinting polymerisation method have a higher adsorption capacity and faster adsorption kinetics than the MIPs produced by the bulk polymerisation method. However, the application of MIPs in the analysis of APIs and drug products are currently only related to organic compounds. Considering the advantages of MIPs to separate impurities, MIPs for other impurities still need to be developed, including multi-template MIPs for simultaneous separation of multiple impurities.

Clinical effect of teicoplanin on pulmonary infection after chemotherapy for hematologic malignancies

OBJECTIVE

To explore the effects of teicoplanin on pulmonary infection after chemotherapy for hematologic malignancies.

METHODS

In the present retrospective study, 64 patients with pulmonary infection, who underwent chemotherapy for hematologic malignancies at Anhui No.2 Provincial People's Hospital from September 2019 to September 2021, were selected as an infection group, and their clinical data were retrospectively analyzed. Meanwhile, 30 patients without pulmonary infection after chemotherapy for hematologic malignancies were selected as a reference group. Patients in the infection group were subdivided into control and treatment groups (n=32 each) according to the different therapeutic regimens. The control group was given routine treatment with norvancomycin, while the treatment group was given teicoplanin combined with norvancomycin. The therapeutic effects, bacterial clearance rate, recovery time, clinical pulmonary infection score (CPIS), inflammatory factors and adverse reactions were compared between the two groups. The risk factors of pulmonary infection after treatment for hematologic malignancies were analyzed.

RESULTS

The treatment group exhibited higher total therapeutic effect and higher bacterial clearance rate than the control group (P < 0.05). The treatment group had shorter time to the recovery of white blood cell (WBC) count, time to the disappearance of cough and sputum, time to return to normal body temperature, and length of stay than the control group (P < 0.05). One month post-treatment, the levels of C-reactive protein, tumor necrosis factor-α, interleukin-1β, and procalcitonin in the treatment group were lower than those in the control group (P < 0.05). The CPISs at 7, 14, and 30 days after treatment were lower in the treatment group than those in the control group (P < 0.05). Compared with the reference group, the infection group had higher rate of diabetes, higher rate of glucocorticoid use, longer time of agranulocytosis, longer hospital stay and lower WBC count (P < 0.05). Multivariate Logistic regression analysis showed that agranulocytosis time, diabetes mellitus and glucocorticoid use were independent risk factors for pulmonary infection after treatment for hematologic malignancies (P < 0.05), and that higher WBC was a protective factor (P < 0.05).

CONCLUSION

Teicoplanin in the treatment of pulmonary infection after chemotherapy for hematologic malignancies can improve the therapeutic effects, effectively clear bacteria, shorten the recovery time and reduce the inflammatory response.

Surface molecularly imprinted solid-phase extraction for the determination of vancomycin in plasma samples using HPLC-MS/MS

Vancomycin is a glycopeptide antibiotic used to treat infections caused by Gram-positive bacteria. Due to the narrow therapeutic index of vancomycin, it is necessary to develop a sensitive and reliable analytical method to monitor the drug concentration in plasma. A novel method based on surface molecularly imprinted solid-phase extraction combined with liquid chromatography-tandem mass spectrometry for the determination of vancomycin in plasma sample was developed. The plasma sample was cleaned up through the solid-phase extraction process before the analysis. The calibration standard of vancomycin in plasma ranged between 1 and 100 ng/mL, and the correlation coefficient (r) was 0.9993. The average recoveries were from 94.3 to 104.0%, and the precision was less than 10.5%. The limit of detection and limit of quantification were 0.5 ng/mL and 1 ng/mL, respectively. The method validated was successfully used for the detection of vancomycin in mice after oral administration.

Surface molecularly imprinted solid-phase extraction for the determination of vancomycin and norvancomycin in milk by liquid chromatography coupled to tandem mass spectrometry

A simple and sensitive method based on surface molecularly imprinted solid-phase extraction (SMISPE) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed to determine the residues of vancomycin (VCM) and norvancomycin (NVCM) in milk samples. The imprinted polymer prepared with teicoplanin as a virtual template can specifically recognize VCM and NVCM. The samples were purified with SMISPE and analyzed by LC-MS/MS in positive ionization mode. The results showed that the VCM and NVCM had a good linear correlation in the range of 0.5 μg/kg to 50 μg/kg. The recoveries of target analytes were from 83.3% to 92.1%, and the limits of quantification were both 1.0 μg/kg. The matrix effects of VCM and NVCM were -11.0% and -3.43%, respectively. The proposed method can efficiently eliminate the interference from matrix compounds and reduce baseline noise, which is useful for the monitoring of the residues of VCM and NVCM in milk samples.

Customizable molecular recognition: advancements in design, synthesis, and application of molecularly imprinted polymers

Molecularly imprinted polymers (MIPs) are unlocking the door to synthetic materials that are capable of molecular recognition.