Thermoresponsive (co)polymers with LCST behavior based on a well-defined PiPOx scaffold showing high versatility in tuning up the TCP as well as the interval of response.

Synthetic polymers have had a major impact on the biomedical field. However, all polymers have their advantages and disadvantages, so that the selection of a certain polymeric material always is a compromise with regard to many properties, such as synthetic accessibility, solubility, thermal properties, biocompatibility and degradability. The development of novel polymers with superior properties for medical applications is the focus of many research groups. The present study highlights the use of poly(2-isopropenyl-2-oxazoline) (PiPOx), as biocompatible functional polymer to develop synthetic hydrogel materials using a simple straightforward synthesis protocol. A library of hydrogels was obtained by chemical cross-linking of PiPOx, using eight different non-toxic and bio-based dicarboxylic acids. The equilibrium swelling degree (ESD) of the final material can be modulated by simple modification of the composition of the reaction mixture, including the polymer concentration in the feed ratio between the 2-oxazoline pendent groups and the carboxylic acid groups as well as the cross-linker 2 length. The hydrogels with the highest water uptake were selected for further investigations regarding their potential use as biomaterials. We evaluated the thermoresponsiveness, the pH-degradability under physiological conditions and demonstrated proof-of-concept drug delivery experiments. The in vitro cellular studies demonstrated the noncytotoxic character of the PiPOx hydrogels, and its protein repellent properties, while mineralization studies revealed that such scaffolds do not promote mineralization/calcification phenomena. In view, of these results, these hydrogels show potential use as ophthalmologic materials or in drug delivery applications.

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Squalene is natural occurring polyprenyl compound with a linear triterpene chemical structure commonly found in animal and vegetal sources such as skin lipids from human body, liver of certain species of fish, especially sharks, crude vegetable oils (e.g olive, amaranth, palm oil etc.). Recently there has been an increasing interest in studying polymers that can be used as promising emulsions for drug delivery and vaccine applications. Recent studies proved that squalene has several beneficial and unique properties such as natural antioxidant, ensure skin hydration, biocompatibility. This can be used as such or for preparing stable and non-toxic emulsions. Herein we present the preparation and characterization of squalene oil-inwater emulsions stabilized by different non-ionic emulsifiers. Emulsion stability is a primary concern, therefore physical stability of squalene emulsions was also investigated. The major aim of the study was to find the optimal preparation conditions and assessing emulsion stability correlated with their viscosity and composition. In order to establish the connection between their physical stability and viscosity were performed rheological studies.

In order to assess the impact of car emissions on the soil, studies are required to monitor the concentation heavy metals from roadside soils. In this paper, we report an extensive survey of the roadside soils contamination with heavy metal along the Sun Highway (A2) which connects Bucharest to Constanta. The contents of heavy metals (Cd, Cu, Ni, Pb, Zn, As) were assessed by inductively coupled plasma mass spectrometry (ICP-MS). The car pollution was also studied to link it with the concentrations and distributions of heavy metals in the roadside soils.A comparison between the degree of contamination obtained in the set points was made. Moreover, the impact of the metal concentration value was debated.