Antimicrobial poly(2-methyloxazoline)s with bioswitchable activity through satellite group modification.

Biocides are widely used for preventing the spread of microbial infections and fouling of materials. Since their use can build up microbial resistance and cause unpredictable long-term environmental problems, new biocidal agents are required. In this study, we demonstrate a concept in which an antimicrobial polymer is deactivated by the cleavage of a single group.

Performance of dielectric barrier discharge ionization mass spectrometry for pesticide testing: a comparison with atmospheric pressure chemical ionization and electrospray ionization.

Rationale: The present study reports on the evaluation of dielectric barrier discharge microplasma ionization (DBDI) for liquid chromatography/high resolution mass spectrometry (LC/HRMS) analyses of pesticide residues in fruit and vegetables. Ionization, fragmentation, analytical performance and matrix effects displayed by LC/DBDI-MS were critically evaluated and compared with both atmospheric pressure chemical ionization (APCI) and electrospray (ESI), using a set of over 40 representative multiclass pesticides.

Methods: Sample preparation was accomplished using standard QuEChERS procedure and the identification and quantitation of the pesticides tested accomplished by means of LC/MS with a hybrid linear quadrupole ion trap (LIT)-Fourier transform ion cyclotron resonance (FTICR) mass spectrometer operated in full-scan positive ion mode using DBDI, APCI and ESI sources.

Well-defined amphiphilic poly(2-oxazoline) ABA-triblock copolymers and their aggregation behavior in aqueous solution.

Self-organization of block copolymers in solution is a way to obtain advanced functional superstructures. The synthesis of well-defined polymethyloxazoline-block-polyphenyloxazoline-block-polymethyloxazoline triblock copolymers is described and proven by (1) H NMR spectroscopy, SEC, and ESI-MS. The surprisingly water- soluble block copolymers do self-organize in aqueous solutions uniquely forming three coexisting well-defined structures: unimolecular micelles, micellar aggregates, and very form-stable polymersomes.

Ultrafiltration behavior of selected pharmaceuticals on natural and synthetic membranes in the presence of humic-rich hydrocolloids.

The separation behavior of the frequently administered pharmaceuticals sulfamethoxazol (Sulfa), carbamazepine (Carba), diclofenac (Diclo), and ibuprofen (Ibu) on different natural and synthetic ultrafiltration membranes was studied. Commercially available cattle intestine natural membranes (NM), polyethersulfone (PES), and regenerated cellulose-based (RC) flat membranes (nominal cut-off 1 kDa) have been investigated as ultrafiltration membranes in a small tangential-flow ultrafiltration unit (TF-UF). First, the nominal cut-off of the NM membranes under study was assessed at approximately 5 kDa, by using polystyrenesulfonate standards for pore-size classification at low TF-UF pressure (0.