Adsorption behaviors and mechanisms of porous hypercrosslinked polymers with adjustable functional groups toward doxycycline hydrochloride from water

Imino hypercrosslinked polymers (NH-HCPs), amino hypercrosslinked polymers (NH₂-HCPs), and carboxyl hypercrosslinked polymers (COOH-HCPs) were synthesized through cross-linking and Friedel-Crafts reactions to serve as highly efficient adsorbents for doxycycline hydrochloride (DOX) in water. These polymers, NH-HCPs, NH₂-HCPs, and COOH-HCPs, exhibited specific surface areas measuring 450, 267.576, and 94.39 m²/g, respectively. The adsorption kinetics of DOX onto these polymers were consistent with the pseudo-second-order model, while the adsorption isotherms followed the Langmuir model (NH-HCPs) and Freundlich model (NH₂-HCPs and COOH-HCPs), respectively. The maximum DOX adsorption capacities for NH-HCPs, NH₂-HCPs, and COOH-HCPs were 166.82, 132.43, and 72.07 mg/g, respectively. Simulation results indicated that COOH-HCPs exhibited the strongest adsorption capability due to a substantial presence of oxygen and nitrogen groups on its surface, enabling the formation of hydrogen bonds with DOX. However, its actual adsorption capacity was the lowest among the polymers, indicating that structural adjustments played a more significant role in improving adsorption performance compared to functional adjustments. Adsorption experiments conducted with NH-HCPs and NH₂-HCPs further supported this hypothesis. The primary DOX adsorption mechanism of NH-HCPs, NH₂-HCPs, and COOH-HCPs involved the H-bonding of oxygen and nitrogen functional groups, along with other mechanisms such as π-π conjugated effects, pore-filling effects, electrostatic interactions, and acid–base interactions. Overall, this study demonstrates the effectiveness of NH-HCPs, NH₂-HCPs, and COOH-HCPs in DOX removal from water, highlighting the significant influence of structural adjustments on adsorption performance.     

Dyeing of wool with antibiotics to develop novel infection resistance materials for extracorporeal end use

Two antibiotics, doxycycline (Doxy) and ciprofloxacin (Cipro), were applied under a variety of conditions to wool and to hydrolyzed wool at 40°C. Nylon was used as a synthetic control. Sorption of Doxy was much higher in wool than in nylon, whereas sorption of Cipro was similar in both fibers. FTIR spectroscopy confirmed that a drastic increase in sorption of antibiotics by hydrolyzed wool was attributed to an increase in polar functional groups by peptide scission and in oxidized sulfur groups by cystine oxidation. Both sorption and zone of inhibition (ZOI) values were improved by hydrolysis of wool. Wool hydrolyzed for 20 or 40 min at 40°C and dyed with Doxy at 45°C for 3.5 h maintained around 30 mm of ZOI after 24 h of challenge by a simulated flow of blood. Wool hydrolyzed for 60 min at 40°C and dyed with Cipro at 45°C for 3.5 h also maintained its antibiotic activity for an extended time. For the most part, ZOI values for nylon dyed by both antibiotics were zero within 24 h. This technique produced infection‐resistant biomaterials of potential use in extra‐corporeal biomedical and biological applications. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3343–3354, 2004     

盐酸多西环素精制母液物料的回收及提纯

采用向精制母液中加5-磺基水杨酸和水的方法,从精制母液中回收出氢化物,并确定了最佳配比：5-磺基水杨酸：水：精制母液=0．025：0．5：1。由于回收氢化物中含有较多的杂质,本文采用新的成品精制方法,解决了成品拖尾峰问题。成品精制的最佳工艺为：温度控制在50℃,活性炭脱色时间20min,活性炭;氯化氢-乙醇：水：多西环素—水合物=0．025：3：3;1。     

In vitro model to assess the adsorption of oral veterinary drugs to mycotoxin binders in a feed- and aflatoxin B1-containing buffered matrix

Mycotoxin binders are feed additives which are mixed in the feed to adsorb mycotoxins and thereby reducing their toxic effects on animals. Interactions with orally administered veterinary medicinal products, such as antimicrobials or coccidiostats, have been reported previously. This paper describes an in vitro model to screen the interaction between mycotoxin binders and veterinary drugs with respect to the non-specific binding of drugs. It is designed as a static setup using a single concentration of drug and binder in a feed-containing or a feed-plus-mycotoxin-containing matrix, buffered at different pH values. The model was applied to two frequently used antimicrobials in veterinary medicine, doxycycline (DOX) and tylosin (TYL), one major mycotoxin, aflatoxin B1 (AFB1), and four mycotoxin binders. Proportions of feed, DOX or TYL, AFB1, and binder are equivalent to the in vivo situation for broiler chickens, while pH and volume of the buffer are representative of the gastrointestinal tract of chickens. A substantial binding of DOX (~ 88%) and TYL (~ 66%) to the feed-matrix was observed. For the mycotoxin binders, similar results were obtained for DOX and TYL; more specifically up to an inclusion rate of 20 g binder/kg feed, no significant binding was demonstrated, determined as the free concentration of DOX and TYL. A single exception was noticed for TYL and one specific bentonite-based mycotoxin binder, for which no significant interaction could be demonstrated up to 10 g binder/kg but there was an effect at 20 g/kg. In all cases, there was no competition between the tested drugs DOX or TYL and the mycotoxin AFB1 for binding to the bentonite-based mycotoxin binder.     

强力霉素废水中氟的处理研究

根据强力霉素含氟废水的特点,采用石灰-粉煤灰两段净化工艺处理其中的氟,并对影响处理效果的主要因素进行了试验研究.结果表明,一段处理最佳条件:m(Ca)∶m(F)=2、反应时间40min;二段处理最佳条件:粉煤灰粒径小于200目,灰水比为1∶10,振荡吸附时间为200min,pH4～8;处理后的废水中氟质量浓度＜10 mg/L,达到了GB 8978-1996《污水综合排放标准》中的一级标准.该方法工艺简单、操作方便、成本低廉.处理废水后的含氟灰渣烧制成砖块,不会对环境造成二次污染,并达到了以废治废的目的.     

Prevalence and antimicrobial resistance of Salmonella isolated from an integrated broiler chicken supply chain in Qingdao,China

The present study analyzed the prevalence and antimicrobial resistance of Salmonella along an integrated broiler chicken supply chain. A total of 172 Salmonella isolates were recovered from 1148 samples collected from four sample sources (breeder farms, broiler farms, abattoir, and retail markets), representing nine production stages. These Salmonella isolates were examined for antimicrobial susceptibility to 12 different antimicrobial agents using a disk diffusion assay. Among them, 168 were identified as six different serotypes of Salmonella enterica. The predominant serotype was S. Enteritidis (n = 116), followed by S. Infantis (n = 18), S. Gueuletapee (n = 16), S. Derby (n = 12), S. Meleagridis (n = 4), and S. London (n = 2). The remaining four isolates were serogroup-untypeable. A majority of the 172 isolates (96.51%) was resistant to one or more antibiotics and 61.05% of the Salmonella isolates showed a multidrug resistance phenotype. Statistical analysis indicated the one risk product stage for Salmonella contamination occurred in the sample source at the abattoir, specifically the stage of Carcasses after chilling. The majority of S. Enteritidis isolates shared the same pulsed-field gel electrophoresis (PFGE) cluster, suggesting that the S. Enteritidis strain might spread along the broiler chicken supply chain. The prevalence and antimicrobial resistance of Salmonella in different production stages suggest the importance of controlling Salmonella in the broiler chicken supply chain for public health, underlying the need for improved measures of reducing carcass contamination in abattoirs and the appropriate use of antimicrobials in broiler flocks.     

Controlled release antibiotics for dry powder lung delivery

Introduction: Two controlled release (CR) antibiotics intended for inhalation therapy were evaluated. Material and Methods: Ciprofloxacin and doxycycline (both hydrochlorides) were selected as model drugs. Microparticles containing 90:10 ratio of polyvinyl alcohol (PVA) and single antibiotics or combinations were obtained via spray drying. The microparticles were evaluated in terms of particle size, morphology, thermal properties, aerosol performance, and in vitro release. Results and Discussion: Analysis of the microparticle morphology indicated comparable size distributions (2.04 ± 0.06, 2.15 ± 0.01, and 2.21 ± 0.01 μm for ciprofloxacin, doxycycline, and co-spray-dried antibiotic formulations, respectively). Thermal analysis of the microparticles suggested similar responses, which were dominated by the endothermic peaks observed for PVA alone. Analysis of the aerosol performance suggested that the individual antibiotic formulations had different aerosol profiles that were dependent on the antibiotic used. In comparison, the combination CR antibiotics had identical aerosol profiles, suggesting that the microparticles were homogeneous. The release of antibiotics from the CR microparticles showed that ≤50% was released over a 6-hour period in comparison to ≥90% being released in the first hour for microparticles containing no PVA. Conclusions: The potential for antibiotic therapy, and specifically CR antibiotic therapy using dry powder inhalers, provides a promising route for the treatment of pulmonary infection.     

醇和小分子有机物二元双水相体系萃取盐酸多西环素

基于小分子醇双水相体系和小分子有机物双水相体系,建立了乙醇与丙酮和(NH4)2SO4形成的二元双水相体系萃取盐酸多西环素的新方法。研究了(NH4)2SO4浓度、pH值、温度、乙醇与丙酮用量和盐酸多西环素浓度对盐酸多西环素分配行为的影响。结果表明,体系的(NH4)2SO4浓度为41%,pH值在4.5～5.0,温度25℃,且盐酸多西环素的质量浓度70 mg/L时,萃取率可达93.61%,分配系数可达83.081。     

强力霉素滴眼液对兔蒸发过强型干眼疗效的评价

目的研究强力霉素滴眼液对兔蒸发过强型干眼的治疗效果,并初步探讨其机理。方法新西兰大白兔16只,烧灼睑板腺开口制作干眼模型,术后第6周随机分为4组,分别不滴药及滴用1%甲基纤维素、0.1%强力霉素、1%甲基纤维素加0.1%强力霉素。用药前后定期检查角膜荧光素染色、虎红染色、结膜杯状细胞密度等。术后第1 1周取眼睑、结膜及角膜行病理检查。结果用药前各组兔角膜荧光素染色、虎红染色、结膜杯状细胞密度等指标无统计学差异(P<0.05)。用药后,甲基纤维素与强力霉素联合应用组荧光素染色及虎红染色比未用药组轻,结膜杯状细胞密度比未用药组高(P<0.05)。单用甲基纤维素或强力霉素组上述指标与未用药组比较无统计学差异(P>0.05)。病理检查未滴药组睑结膜及球结膜可见炎症细胞浸润,其它组未见明显的炎症细胞浸润。结论强力霉素滴眼液可以减轻干眼兔眼表的炎症反应,与甲基纤维素联合应用对兔蒸发过强型干眼有一定的治疗效果,提示强力霉素治疗干眼具有一定的应用前景。