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Molecularly imprinted nanotubes for enantioselective drug delivery and controlled release are fabricated by the combination of template synthesis and ATRP grafting. The release of R-propranolol from the imprinted nanotubes in rats is restricted while the release of pharmacologically active S-enantiomer is greatly promoted.

To assess the potential risks associated with the environmental exposure of beta-lactam antibiotics (BLAs), the monitoring of the occurrence, distribution, and fate of these emerging contaminants in the environment is required. Herein, we demonstrate a molecularly imprinted solid-phase extraction (MISPE) method for selective and reliable screening of trace BLAs in river and tap water. By developing a low-temperature photopolymerization, highly selective molecularly imprinted polymers (MIPs) for five BLAs (penicillin G, amoxicillin, ampicillin, nafcillin and mezlocillin) were synthesized. Nafcillin was chosen as a pseudo template to make the MIP sorbent (Nafc-MIP), which was used in pseudo-template MISPE for preconcentration of the other four BLAs from river and tap water. The application of pseudo-template MISPE overcomes the template bleeding, which significantly elevates the sample background and restricts the application of MIP for detection of the target BLA below 2 microg/L. The average recoveries of BLAs are in the range of 60-90% when Nafc-MIP was adopted as the selective MISPE sorbent. The developed method was validated, and applied to the screening of trace beta-lactam antibiotics in river and tap water. The linearity of the calibration curve for each BLA was observed over the range of 0.1-20 microg/L (r>0.998). The beta-lactam antibiotics were found within the range of 0-9.56 microg/L in river water at the downstream of antibiotics manufacturers, and none were detected in the tap water., (2010 Elsevier B.V. All rights reserved.)

• A new molecular imprinting graphene nanocomposite (PIL-MIP/GO) was synthesized. • PIL-MIP/GO has fast mass transfer, rich adsorption mechanism, and high selectivity. • A HPLC-UV method for β-agonists was designed based on PIL-MIP/GO as PT-SPE sorbent. • The method was successfully applied to detect β-agonist in swine urine. • The analytical method was sensitive, selective, accurate, nonfatal, and economical. The illegal use of β-agonists often endangers animal-derived food safety. In this study, a selective detection method for β-agonists in swine urine was established via the combination of polymeric ionic liquid-molecularly imprinted graphene oxide-miniaturized pipette tip solid-phase extraction and high-performance liquid chromatography. It is worth noting that this method relied mainly on the designed adsorbent, which presented a rich adsorption mechanism, fast mass transfer rate, and high selectivity, and was successfully utilized in the selective extraction of β-agonists from swine urine samples. The proposed method has low LOD (0.20–0.56 ng/mL), high recovery (94.9–107.9%), and high reusability (4 times, 91.9–108.8%), which indicates its high potential as a selective, sensitive, accurate, and nonfatal method for monitoring the illegal use of β-agonists in the livestock breeding stage. [ABSTRACT FROM AUTHOR]