Synthesis and positive inotropic activity evaluation of liguzinediol metabolites.

2,5-Dihydroxymethyl-3,6-dimethylpyrazine (liguzinediol) has been recently discovered as a potential agent for treatment of heart failure with low safety risk. In the present study, four main metabolites of liguzinediol were synthesized and their positive inotropic activities were evaluated. Synthetic compounds were identical with the isolated metabolites of liguzinediol. Pharmacological examinations showed that the four major metabolites were not observed positive inotropic activity, and revealed that the positive inotropic activity of liguzinediol was essentially attributed to the parent agent.

Hepatoprotective triterpene saponins from the roots of Glycyrrhiza inflata.

Two novel oleanane-type triterpene saponins, licorice-saponin P2 (1) and licorice-saponin Q2 (3), together with nine known compounds 2, 4-11, have been isolated from the water extract of the roots of Glycyrrhiza inflata. The structures of these compounds were elucidated on the basis of spectroscopic analysis, including 2D-NMR experiments (1H-1H COSY, HSQC, HMBC and ROESY). In in vitro assays, compounds 2-4, 6 and 11 showed significant hepatoprotective activities by lowering the ALT and AST levels in primary rat hepatocytes injured by D-galactosamine (D-GalN). In addition, compounds 2-4, 6, 7 and 11 were found to inhibit the activity of PLA2 with IC50 values of 6.9 µM, 3.6 µM, 16.9 µM, 27.1 µM, 32.2 µM and 9.3 µM, respectively, which might be involved in the regulation of the hepatoprotective activities observed.

Total synthesis and anti-viral activities of an extract of Radix isatidis.

Radix isatidis (Banlangen), a famous traditional Chinese medicine, has been used for thousands of years in China due to its anti-viral activity. Through our research, we inferred that the anti-viral activity of Radix isatidis depended on the water-soluble part. Among the components of this extract, the isoquinoline derivative 1 was isolated for the first time and has shown better anti-viral activity than other constituents. In this study, to solve the problem of sourcing sufficient quantities of compound 1, a total synthesis route is described, and several analogues are also evaluated for their anti-viral activities. Among them, compound 8 shown potent anti-viral activity with an IC50 value of 15.3 µg/mL. The results suggested that isoquinoline derivatives possessed potent anti-viral activity and are worthy further development.

Synthesis and biological evaluation of liguzinediol mono- and dual ester prodrugs as promising inotropic agents.

The potent positive inotropic effect, together with the relatively low safety risk of liguzinediol (LZDO), relative to currently available inotropic drugs, has prompted us to intensively research and develop LZDO as a potent positive inotropic agent. In this study, to obtain LZDO alternatives for oral chronic administration, a series of long-chain fatty carboxylic mono- and dual-esters of LZDO were synthesized, and preliminarily evaluated for physicochemical properties and bioconversion. Enhanced lipophilic properties and decreased solubility of the prodrugs were observed as the side chain length increased. All esters showed conspicuous chemical stability in phosphate buffer (pH 7.4). Moreover, the enzymatic hydrolysis of esters in human plasma and human liver microsomes confirmed that the majority of esters were converted to LZDO, with release profiles that varied due to the size and structure of the side chain. In vivo pharmacokinetic studies following oral administration of monopivaloyl (M5), monodecyl (M10) and monododecyl (M12) esters demonstrated the evidently extended half-lives relative to LZDO dosed alone. In particular the monopivaloyl ester M5 exhibited an optimal pharmacokinetic profile with appropriate physiochemical characteristics.

[Study on water-soluble chemical constituents of Taraxacum mongolicum].

OBJECTIVE: To study the water-soluble chemical constituents of Taraxacum mongolicum. METHODS: The chemical constituents were isolated and purified by means of several chromatographic techniques and their structures were elucidated by spectroscopic methods. RESULTS: Nine compounds were isolated and identified as trans-p-coumaryl alcohol(1), trans-p-coumaryl aldehyde(2),p- hydroxybenzoate (3) , p-hydroxyphenyl-propionic acid (4) , 4-hydroxy-2, 6-dimethoxyphenol-1 -O-ß-D-glucopyranoside (5) , protocate- chuic aldehyde(6) ,rutin(7) ,quercetin(8) ,kaempferal-3-O-α-L-rhamnopyranosyl-( 1-6) -ß-D-glucopyranoside(9). CONCLUSION: Com pounds 1-6 are isolated from this plant for the first time.

[Chemical constituents from flower of Lonicera fragrantissima].

OBJECTIVE: To study the chemical constituents from the flower of Lonicera fragrantissima. METHODS: The chemical constituents were isolated and purified by means of several chromatographic techniques, and their structures were elucidated by spectroscopic methods. RESULTS: Nine compounds were isolated and identified as chlorogenic acid (1), caffeic acid (2), secologanoside (3), secoxyloganin(4), loganin (5), sucrose (6), myo-inositol (7), rutin (8), and chrysoeriol-7-O-ß-D-glucoside (9). CONCLUSION: Compounds 2-9 are obtained from this plant for the first time.

Patients' expectancy scale of acupuncture: Development and clinical performance test.

PURPOSE: This study aims to develop and validate a concise tool for evaluating acupuncture expectancy that is easy to understand and conforms to acupuncture characteristics. MATERIALS AND METHODS: A draft was created using the Delphi consensus method. Reliability, validity, discrimination, and feasibility tests were conducted at the item and scale levels. RESULTS: The scale themes were defined as disease-related, treatment-related, process-related, and outcome-related. After two rounds of Delphi surveys with good experts' reliability (authority coefficients of experts were 0.86 and 0.87 in the two rounds) and agreement (Kendall's concordance coefficient of the participants were 0.33 and 0.15 in the two rounds, P < 0.05), 11 items (the mean score for item importance, full mark ratios, and coefficient of variation of items were ≥3.5, ≥25%, and ≤0.30, respectively) were included in the draft. A total of 145 individuals were recruited to test the draft. Reliability was assessed by Cronbach's α coefficient (0.90), split-half reliability coefficient (0.89), and test-retest reliability (Pearson's coefficient = 0.74, P < 0.05). Content validity was assessed by the content validity index (Item-CVI ≥ 0.78 and Scale-CVI/Ave = 0.92), and a confirmatory factor analysis was performed to assess the construct validity. The discrimination of scale items was evaluated by the critical ratio (CR > 3.00) and the homogeneity test (item-total correlations >0.40). Feasibility was assessed through the acceptance rate (recovery rate = 98.60%, response rate = 100%), completion rate (100%), and completion time (4.99 ± 6.80 min). CONCLUSION: The patients' expectancy scale of acupuncture (PESA) consists of 11 items with four themes, disease-related, treatment-related, process-related, and outcome-related. It has great reliability, validity, discrimination, and feasibility and has the potential to evaluate acupuncture expectancy in clinical trials.

Investigation of growth characteristics and semimetal-semiconductor transition of polycrystalline bis-muth thin films.

The preferred orientation growth characteristics and surface roughness of polycrystalline bis-muth (Bi) thin films fabricated on glass substrates using the molecular beam epitaxy method were investigated at temperatures ranging from 18 to 150°C. The crystallization and morphology were analyzed in detail and the polycrystalline metal film structure-zone model (SZM) was modified to fit the polycrystalline Bi thin film. The boundary temperature between Zone T and Zone II in the SZM shifted to higher temperatures with the increase in film thickness or the decrease of growth rate. Furthermore, the effect of the thickness and surface roughness on the transport properties was investigated, especially for Bi thin films in Zone II. A two-transport channels model was adopted to reveal the influence of the film thickness on the competition between the metallic surface states and the semiconducting bulk states, which is consistent with the results of Bi single-crystal films. Therefore, the polycrystalline Bi thin films are expected to replace the single-crystal films in the application of spintronic devices.

Diagnosis and treatment recommendations for pediatric respiratory infection caused by the 2019 novel coronavirus.

Since December 2019, an epidemic caused by novel coronavirus (2019-nCoV) infection has occurred unexpectedly in China. As of 8 pm, 31 January 2020, more than 20 pediatric cases have been reported in China. Of these cases, ten patients were identified in Zhejiang Province, with an age of onset ranging from 112 days to 17 years. Following the latest National recommendations for diagnosis and treatment of pneumonia caused by 2019-nCoV (the 4th edition) and current status of clinical practice in Zhejiang Province, recommendations for the diagnosis and treatment of respiratory infection caused by 2019-nCoV for children were drafted by the National Clinical Research Center for Child Health, the National Children's Regional Medical Center, Children's Hospital, Zhejiang University School of Medicine to further standardize the protocol for diagnosis and treatment of respiratory infection in children caused by 2019-nCoV.

Deprotonation-Induced Conductivity Shift of Polyethylenedioxythiophenes in Aqueous Solutions: The Effects of Side-Chain Length and Polymer Composition.

Deprotonation-induced conductivity shift of poly(3,4-ethylenedixoythiophene)s (PEDOTs) in aqueous solutions is a promising platform for chemical or biological sensor due to its large signal output and minimum effect from material morphology. Carboxylic acid group functionalized poly(Cn-EDOT-COOH)s are synthesized and electrodeposited on microelectrodes. The microelectrodes are utilized to study the effect of carboxylic acid side-chain length on the conductivity curve profiles in aqueous buffer with different pH. The conductivity shifts due to the buffer pH are effected by the length of the carboxylic acid side-chains. The shifts can be explained by the carboxylic acid dissociation property (pKa) at the solid-liquid interface, self-doping effect, and effective conjugation length. Conductivity profiles of poly(EDOT-OH-co-C2-EDOT-COOH) copolymers are also studied. The shifts show linear relationship with the feed monomer composition used in electrochemical polymerization.

Viral pathogens of acute lower respiratory tract infection in China.

OBJECTIVES: To document the viral etiology of acute lower respiratory tract infection (ALRIs) in Chinese children. SETTING: Children Hospital, Zhejiang University, China. STUDY DESIGN: Cross-sectional. PARTICIPANTS: 34885 children with ALRI between January 2001 to December 2006. METHODS: Nasopharyngeal aspirates were collected from all subjects. Respiratory syncytial virus (RSV), adenovirus (ADV), type 1 to 3 parainfluenza viruses (PIV), and type A and B influenza virus (Flu) were detected by direct immunofluorescence. RESULTS: Viruses were identified in 32.3% cases, including RSV (23.6%), PIV 3 (4.3%), Flu A (2.0%), ADV (1.7%), PIV I (0.6%), Flu B (0.2%) and PIV 2 (0.1%). RSV and PIV 3 predominated in younger children while Flu A and Flu B predominated in older children (P<0.001, respectively). PIV 1 was more prevalent in children aged 1 to 3 years. The peak frequency of RSV, PIV 3 and Flu A were in early spring, June to August, and August and September, respectively. Flu B had a peak in the winter and spring. Adenovirus infections occurred in all seasons with a relatively constant frequency. CONCLUSIONS: Viruses are an important cause of ALRIs in Chinese children constituting 1/3 of total cases. RSV is the most common pathogen.

Stat5-dependent cardioprotection in late remote ischaemia preconditioning.

Aims: To study the protective effects of late remote ischaemic preconditioning (RIPC) against myocardial ischaemia/reperfusion (I/R) injury and determine whether Stat5 is involved in this protection by using cardiomyocyte-specific Stat5 knockout mice (Stat5-cKO). Methods and results: Mice were exposed to lower limb RIPC or sham ischaemia. After 24 h, the left anterior descending artery (LAD) was ligated for 30 min, then reperfused for 180 min. The myocardial infarct size (IS), apoptotic rate of cardiomyocytes, and serum myocardial enzymes were measured to evaluate for cardioprotective effects. Heart tissues were harvested to determine the cardiomyocytes' anti-apoptotic and survival signaling. When compared with the Stat5fl/fl mice without RIPC, Stat5fl/fl mice with RIPC (Stat5fl/fl+RIPC + I/R) displayed a decreased myocardial IS/LV (16 ± 1.5 vs. 30.1 ± 3.1%, P < 0.01; IS/ area at risk (AAR), 42.2 ± 3.5 vs. 69.2 ± 4.9%, P < 0.01), a reduced cardiomyocyte apoptotic rate (2.1 ± 0.37 vs. 5.5 ± 0.53%, P < 0.01), and lower creatine kinase (CK), lactate dehydrogenase (LDH), and creatine kinase-MB (CK-MB) levels. To the contrary, the Stat5-cKO mice (Stat5fl/fl; Tnnt2Cremice with Doxycycline treatment for 7 days) did not exhibit any effect of RIPC-induced cardioprotection. Activation of STAT5 protein was significantly higher in the Stat5fl/fl+RIPC + I/R group than in the Stat5fl/fl+I/R group, while there was no significant difference between the Stat5-cKO + RIPC + I/R and the Stat5-cKO + I/R group. Further analyses with heart tissues detected decreased protein expressions of cytochrome c (Cyt c) and cleaved Caspase-3 in the Stat5fl/fl+RIPC + I/R mice, along with increased anti-apoptotic molecules, including B-cell lymphoma-extra large (Bcl-xL) and B-cell lymphoma-2 (Bcl-2); such changes were not noted in the Stat5-cKO + RIPC + I/R mice. Additionally, RIPC increased cardiac hypoxia inducible factor-1 (HIF-1α) and interleukin-10 (IL10) protein levels and caused activation of AKT, phosphatidylinositol 3 kinase (PI3K), and vascular endothelial growth factor in the heart of the Stat5fl/fl mice. However, these changes were completely inhibited by the absence of Stat5. Conclusions: These results suggest that RIPC-induced late cardioprotection against myocardial I/R injury is Stat5-dependent and is correlated with the activation of anti-apoptotic signaling and cardiomyocyte-survival signaling.

Genome-wide regulation of electro-acupuncture on the neural Stat5-loss-induced obese mice.

Acupuncture is reported to be effective in treating obesity related illnesses, but its mechanism is still unclear. To investigate this mechanism we applied electro-acupuncture (EA) in a mouse model of obesity and used RNA-seq to identify molecular consequences. Deletion of the transcription factor STAT5 from neurons (Stat5NKO) led to obesity. Acupuncture, in turn, reduced body weight and the ratio of epididymal white adipose tissue (Epi-WAT) to body weight, and it also decreased plasma concentrations of glucose, triglyceride, and cholesterol. In addition, EA increased cold endurance of Stat5NKO obese mice. EA reversed altered gene expressions in the hypothalamus and Epi-WAT, especially in the hypothalamus in Stat5NKO obese mice. This study provides, for the first time, insight into genomic networks of obesity and their modulation by electro-acupuncture, which in turn reveals potential mechanisms that explain acupuncture-induced weight-loss.

[Noncardiac chest pain and gastroesophageal reflux in children].

OBJECTIVE: To investigate the relationship between noncardiac chest pain (NCCP) and gastroesophageal reflux (GER) in children and to assess the diagnostic value of esophageal pH monitoring in patients with NCCP. METHODS: Ambulatory 24 h esophageal pH monitoring was performed in 36 NCCP cases (patient group) with recurrent chest pain and without respiratory diseases and musculoskeletal abnormalities in chest, and 20 of them underwent gastric endoscopy. Eleven of the 20 cases were found to have esophagitis (esophagitis group), while the other 9 cases showed no signs of esophagitis (non-esophagitis group) according to the diagnostic criteria of esophagitis. RESULTS: The episode of esophageal pH < 4, the number of reflux longer than 5 min, the longest reflux time, the percent time of pH < 4 and Boix-Ochoa score in the patient group were 60 +/- 7, 2.44 +/- 0.74, (12.4 +/- 2.8) min, 6.72 +/- 1.39, 24.6 +/- 3.9, respectively, as compared to 33 +/- 4, 0.35 +/- 0.11, (4.3 +/- 0.9) min, 1.25 +/- 0.19, 7.7 +/- 0.9 in the control group. The difference between the two groups had reached significance (t = 3.44, 2.79, 2.73, 3.89, 4.24, respectively, all P < 0.01). The positive rate of acid reflux in the patient group was 58.3% (21/36) whose Boix-Ochoa score higher than 11.99. Eleven of the 20 cases (55.0%) receiving endoscopy were found to have esophagitis, among them the positive rate of GER occurred 81.8% (9/11). Whereas, the other 9 cases (45.0%, 9/20) showed non-esophagitis and the positive rate of GER showed 33.3% (3/9). The number of reflux longer than 5 min and the percent time of pH < 4 in the esophagitis group were 5.8 +/- 2.0, 12.5 +/- 3.5, respectively, as compared to 0.9 +/- 0.5, 3.4 +/- 1.4 in the non-esophagitis group. Significant difference were observed between the two groups (Z = -2.400, -2.545, respectively, all P < 0.05). The episode of esophageal pH < 4, the longest reflux time, and Boix-Ochoa score in the esophagitis group were 73 +/- 11, (26.4 +/- 7.3) min, 41 +/- 10, respectively, as compared to 34 +/- 11, (4 +/- 3) min, 14 +/- 5 in the non-esophagitis group. The difference between the two groups showed significance (Z = -2.926, -2.675, -2.584, respectively, all P < 0.01). CONCLUSIONS: GER is very common in children with NCCP. Esophageal pH monitoring has a therapeutic predictive value in addition to its diagnostic merit for NCCP in children.

Thrombocytopenia in Patients Receiving Prolonged Linezolid May be Caused by Oxidative Stress.

BACKGROUND AND OBJECTIVES: Oxidative stress in drug-induced thrombocytopenia (TP) has been discussed. This study was carried out to assess the oxidative stress in patients with normal platelet count (NPC) and TP after linezolid (LZD) treatment and to evaluate if TP caused by LZD is associated with a reduction in antioxidation ability and an increase in lipid peroxidative product in platelets. METHODS: After LZD treatment for 20 days, 44 patients with TP and 73 patients with NPC were included in this study. Blood samples were collected on the day before medicine treatment and day 7, 14, and 20 after LZD therapy. Levels of reactive oxygen species (ROS), malondialdehyde (MDA), and cholesterol as well as the activities of antioxidative enzyme were estimated. In addition, we identified 37 patients with TP caused by low-dose methotrexate (7.5-25 mg/week) therapy as a positive control group. RESULTS: In total, 37.60% of cases presented with TP on the 20th day of LZD administration. Individuals with TP had significantly elevated levels of ROS and MDA, low levels of superoxide dismutase (SOD) and catalase (CAT), significantly decreased high-density lipoprotein-cholesterol, low-density lipoprotein (LDL)-cholesterol levels, and increased oxidized-LDL levels in comparison to individuals with NPC. However, no significant changes in the levels of glutathione-peroxidase were found in the course of time. In all cases with LZD, significant increases in levels of ROS, MDA, and ox-LDL were found in the 20-day samples compared with their respective samples before LZD treatment. Correlation analysis revealed a positive association between platelet count and levels of SOD on day 20 and CAT on days 14 and 20 in plasma, a negative association between platelet count and level of MDA and ROS on days 14 and 20 in patients with LZD-induced TP. CONCLUSIONS: The oxidative stress markers were increased in LZD-induced TP, suggesting that oxidative damage might be the underlying mechanism.

[Viral etiology of pneumonia in children].

OBJECTIVE: To evaluate the viral pathogen of pneumonia in children. METHODS: A total of 13 642 cases of children pneumonia in 3 years were enrolled in this study. Antigens of viral pathogen in respiratory excretion, including respiratory syncytial virus (RSV), type 1, 2 and 3 parainfluenza virus, type A and B influenza virus, and adenovirus were detected by direct immunofluorescence method. RESULTS: Viral pneumonia accounted for 34.3% of all cases, including 25.8% cases of RSV, 4.7% of parainfluenza virus, 2.4% of type A influenza virus, 0.2% of type B influenza virus and 1.3% of adenovirus. Coinfection was found in 20 cases, in which 17 cases (85%) were infected with RSV and another virus. Positive rates of RSV in children < or = 1 year, 1 to 3 years, and >3 years were 33.1%, 19.7% and 5.1% with a significant difference (chi(2)(trend)=763.4, P < 0.001). The positive rate of adenovirus in children < or =1 year (0.7%) was significantly lower than that in children aged 1 to 3 years and in children >3 years (2.3% and 2.5%) (all P<0.01). The positive rate of type A influenza virus in children aged 1 to 3 years was higher than that in children < or =1 year (chi(2)=18.2, P<0.01). Type 1 parainfluenza virus was found in 1.2% children aged 1 to 3 years with most prevalence (P<0.05). Infection rates of type 3 parainfluenza in children < or =1 year, 1 to 3 years, and >3 years were 4.7%, 3.2% and 1.4% respectively with a significant difference (chi(2)(trend)=52.4, P<0.01). Although there were some differences of infection rate of RSV in different years, it tended to increase from November to next April with a highest rate of 62.8%. Type 3 parainfluenza virus and Type A influenza virus were almost sporadic while type A influenza virus was epidemic in August 2003 with an infection rate of 15.7%. CONCLUSION: The highest infection rate of viral pathogen of pneumonia in children is RSV and the follows are parainfluenza, influenza and adenovirus in turn.

Identification, Characterization, Synthesis and Quantification of Related Impurities of Liguzinediol.

An HPLC method was employed to create an impurity profile for liguzinediol as an active pharmaceutical ingredient (API), which resulted in the identification of two related impurities. Therefore, in order to improve the quality control of the liguzinediol-API, we identified and then developed a method for quantifying the two impurities (impurity-1 and impurity-2) by LC-TOF-MS-MS and then chemically synthesized them for further studies. Based on spectral data from IR, MS, (1)H and (13)C NMR, the structures of impurity-1 and impurity-2 were characterized as 2-hydroxymethyl-3,6-dimethylpyrazine and 2-hydroxymethyl-3,5,6-trimethylpyrazine, respectively. We further validated the method according to the International Conference on Harmonization guidelines to demonstrate the sensitivity, precision, linearity, accuracy and stability of the method described. In addition, the potential mechanisms underlying formation of impurity-1 and impurity-2 in the liguzinediol-API are discussed in detail.

Harnessing Excited-State Intramolecular Proton-Transfer Reaction via a Series of Amino-Type Hydrogen-Bonding Molecules.

A series of new amino (NH)-type hydrogen-bonding (H-bonding) compounds comprising 2-(2'-aminophenyl)benzothiazole and its extensive derivatives were designed and synthesized. Unlike in the hydroxyl (OH)-type H-bonding systems, one of the amino hydrogens can be replaced with electron-donating/withdrawing groups. This, together with a versatile capability for modifying the parent moiety, makes feasible the comprehensive spectroscopy and dynamics studies of amino-type excited-state intramolecular proton transfer (ESIPT), which was previously inaccessible in the hydroxyl-type ESIPT systems. Empirical correlations were observed among the hydrogen-bonding strength (the N-H bond distances and proton acidity), ESIPT kinetics, and thermodynamics, demonstrating a trend that the stronger N-H···N hydrogen bond leads to a faster ESIPT, as experimentally observed, and a more exergonic reaction thermodynamics. Accordingly, ESIPT reaction can be harnessed for the first time from a highly endergonic type (i.e., prohibition) toward equilibrium with a measurable ESIPT rate and then to the highly exergonic, ultrafast ESIPT reaction within the same series of amino-type intramolecular H-bond system.

[Study on application of PCR in the diagnosis of Haemophilus influenzae pneumonia]

OBJECTIVE: To study the role of Haemophilus influenzae(Hi) in pneumonia and that of PCR in the diagnosis of Hi pneumonia. METHODS: Hi genus-specific PCR, Hib type-specific PCR and selective Hi culture media were used to detect 83 samples of deep nasal pharyngeal aspiration (NPA), 51 sera from 83 children younger than 3 years with pneumonia and 37 samples of pharyngeal swabs from healthy children. RESULTS: Of 83 NPA samples, 20(24.1 %) were positive by culture, 36 (43.4 %) positive by Hi-PCR and 19 (22.9 %) positive by Hib-PCR.Six out of 51 sera were positive by Hi-PCR and Hib-PCR, but none positive by culture. Of 37 pharyngeal swabs from healthy children, 3 ( 8.1 %) were positive by culture, 6 ( 16.2 %) positive by Hi-PCR and none positive by Hib-PCR. CONCLUSION: Hib-PCR is more appropriate for detecting NPA samples from children with pneumonia because of the high rate of non-typeable Hi carriers in healthy children.

Fabrication of enrofloxacin imprinted organic-inorganic hybrid mesoporous sorbent from nanomagnetic polyhedral oligomeric silsesquioxanes for the selective extraction of fluoroquinolones in milk samples.

This paper reports a nanomagnetic polyhedral oligomeric silsesquioxanes (POSS)-directing strategy toward construction of molecularly imprinted hybrid materials for antibiotic residues determination in milk samples. The imprinted polymeric layer was facilely obtained through the copolymerization of active vinyl groups present on the nanomagnetic POSS (Fe3O4@POSS) surface and functional monomer (methacrylic acid) binding with template (enrofloxacin). Herein, the octavinyl POSS acted as not only the building blocks for hybrid rigid architectures but also the cross-linker for the formation of effective recognition sites during the imprinting process. The molecularly imprinted Fe3O4@POSS nanoparticles (Fe3O4@MI-POSS) demonstrated much higher adsorption capacity and selectivity toward enrofloxacin molecules and its analogs than the non-imprinted Fe3O4@POSS (Fe3O4@NI-POSS) materials. The imprinted particles were applied as a selective sorbent in solid-phase extraction focusing upon sample pretreatment in complex matrices prior to chromatographic analysis. The three FQs (ofloxacin, enrofloxacin, danofloxacin) could be selectively extracted from the biological matrix, while the matrix interferences were effectively eliminated simultaneously under the optimum extraction conditions. A simple, rapid and sensitive method based on the Fe3O4@MI-POSS material combined with HPLC-UV detection was then established for the simultaneous determination of three FQs from milk samples. The average recoveries of the three FQs were in the range of 75.6-108.9%. The relative standard deviations of intra- and inter-day ranging from 2.91 to 8.87% and from 3.6 to 11.5%, respectively. The limits of detections (S/N=3) were between 1.76 and 12.42 ng mL(-1). It demonstrates the effectiveness of trace analysis in complicated biological matrices utilizing magnetic separation in combination with molecularly imprinted solid-phase extraction, the rich chemistry of POSS makes it possible to be an ideal platform for generating molecular imprinted hybrid materials is also exhibited.