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IntroductionIn patients with limited peritoneal metastasis (PM) originating from colorectal cancer, cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is a potentially curative treatment option. This combined treatment modality using HIPEC with mitomycin C (MMC) for 90 minutes proved to be superior to systemic chemotherapy alone, but no benefit of adding HIPEC to CRS alone was shown using oxaliplatin-based HIPEC during 30 minutes. We investigated the impact of treatment temperature and duration as relevant HIPEC parameters for these two chemotherapeutic agents in representative preclinical models. The temperature- and duration- dependent efficacy for both oxaliplatin and MMC was evaluated in an in vitro setting and in a representative animal model. MethodsIn 130 WAG/Rij rats, PM were established through i.p. injections of rat CC-531 colon carcinoma cells with a signature similar to the dominant treatment-resistant CMS4 type human colorectal PM. Tumor growth was monitored twice per week using ultrasound, and HIPEC was applied when most tumors were 4-6 mm. A semi-open four-inflow HIPEC setup was used to circulate oxaliplatin or MMC through the peritoneum for 30, 60 or 90 minutes with inflow temperatures of 38 degrees C or 42 degrees C to achieve temperatures in the peritoneum of 37 degrees C or 41 degrees C. Tumors, healthy tissue and blood were collected directly or 48 hours after treatment to assess the platinum uptake, level of apoptosis and proliferation and to determine the healthy tissue toxicity. ResultsIn vitro results show a temperature- and duration- dependent efficacy for both oxaliplatin and MMC in both CC-531 cells and organoids. Temperature distribution throughout the peritoneum of the rats was stable with normothermic and hyperthermic average temperatures in the peritoneum ranging from 36.95-37.63 degrees C and 40.51-41.37 degrees C, respectively. Treatments resulted in minimal body weight decrease (

Fonds Wetenschappelijk Onderzoek (FWO) SB-1S92022N

Pectins are a group of polysaccharides commonly used in industry as gelling, emulsifying, and stabilizing agents. Traditionally obtained from apple or citrus peel, the increasing global demand for pectin calls for the study of alternative sources [1], [2] . Although currently employed in animal feed, carrot pomace, a by-product obtained after juice production, is considered a good target for pectin extraction [3], [4] . Nevertheless, modifications on the chemical structure during biomass storage have been reported [5] , and there is a limited knowledge on changes occurring during pectin extraction. Industrial exploitation of carrot pomace requires the development of robust analytical methods to collect information about the variation in composition through the sample. FTIR microspectroscopy allows the acquisition of spectral and spatial information simultaneously but is not widely implemented in biomass samples due to the inherent limitations of the technique. Uncontrolled physical and chemical phenomena such as changes in sample size, humidity, or instrumental drift are responsible for spectral variance, hindering the potential of this technique for quantitative analysis [6] . Data pre-processing methods can remove the inherent variation in FTIR- spectra but can generate artifacts [7] . Normalization of the spectra based on the signal of an internal standard could overcome this limitation [8] . Nevertheless, internal standardization is not usually employed on biological samples due to the difficulty of finding compounds exhibiting no spectral interference. This work aims to study the feasibility of internal standardization to develop a spectroscopic method for pectin determination on carrot pomace. In a first step, a calibration model for pectin determination was prepared, enriching carrot pomace residues obtained after pectin extraction with different percentages of pectin and a constant amount of internal standard. Subsequently, the calibration model was tested on samples subjected to internal standardization and analyzed by FTIR microspectroscopy. Our results show the potential of this approach in FTIR imaging, where internal standardization could provide a method to quantitatively assess the spatial distribution of pectin in complex biomass matrices. The findings open up an attractive prospect of using FTIR microspectroscopy for mapping changes of target compounds at different stages of extraction. This study is funded by Flanders’ Food and VLAIO in the framework of the EffSep project (Grant number HBC.2019.0012)

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Inkjet printing is a fast, cheap and flexible method to deposit thin and structured layers. In this work precursor based Ag inks were developed instead of the commercially available particle based ones that usually have to be sintered at temperatures of at least 200 °C. It is proven that inkjet printed Ag layers can be sintered at temperatures as low as 60 °C reaching a resistance of less than 5 Ohms/cm with these home-made precursor inks. The author would like to thank the financial contribution from the CORNET project POLEOT (IWT-TETRA-120629) and the support from BOF (Bijzonder OnderzoeksFonds) of Hasselt University.

FWO project G014913, BOF Uhasselt

FWO project G014913, BOF Uhasselt

Cu electroplating has been used for interconnect and more recently 3-D stacking in integrated circuits. Although the reaction mechanisms in additive-free CuSO4 solutions seems straightforward at first sight, the roles of inorganic species such as Cu+ and dissolved oxygen still require a closer look. The Rotating Ring-Disk Electrode (RRDE) can be employed to detect the Cu+ intermediate during the Cu plating process. It has been proven a very useful tool for such a study. The effects of various species on Cu plating, under different conditions, were studied using RRDE in [1]. It was also shown that the addition of Cu2O into the Cu plating bath leads to increased Cu plating rate [2]. While Cu+ is supposed to be directly or indirectly responsible for such acceleration, the underlying mechanism is not yet clear. By maintaining a very low O2 concentration through purging with N2 gas for an extended time, Cu+ generated from the comproportion reaction accumulates and leads to a bulk concentration of Cu+. This provides an opportunity to study the Cu plating rate with additional bulk Cu+ but without O2. Fig.1 shows rotating-ring-disk voltammograms (RRDV) for different bath compositions. For both Fig.1a and Fig.1b, the bulk Cu+ concentration increases significantly at very low O2 concentration, as indicated by the increased background ring current. However, there is no significant change of disk current. A careful check of the disk currents in both figures will even show slight decreases for lower O2 and higher Cu+ concentrations. Fig.2 shows the steady-state measurement, it is shown clearly that, with Cu+ accumulated in the bulk at very low O2 concentration, the disk current is lower compared with the ambient case. Therefore, Cu+ itself is not the cause of increased Cu plating rate. Instead, the formation of Cu(I) oxide, or other forms of Cu-O bounding on the Cu surface in the presence of dissolved O2, is likely responsible for the faster Cu plating rate at ambient condition. It is also consistent with the increased plating rate observed in [2], as Cu2O, not Cu+ ion, was added to the plating bath. Since Cu2O is thermodynamically unstable in an acidic electrolyte, it probably exists as active intermediates with a short lifespan. The Cu plating rate is higher around these active intermediates. At ambient condition, these active intermediates are formed at greater number due to the dissolved O2. With the dissolved O2 been removed through purging with N2 gas, the formation of Cu2O is reduced and the plating rate is lower. In the Cyclic RRDV curves shown in reported RRDE studies [1, 2], as well as the curves in Fig.1 and Fig.2, a small plateau is always present in the ring current curve around the Open Circuit Potential (OCP). Although this plateau is typically ignored, it cannot be predicted by a simple Butler-Volmer equation. Yokoi [1] attributed this plateau to the surface diffusion of Cu adatom to the lattice site. Fig. 3 shows the ring current in two consecutive CV scans. While the plateau is evident in the 1st scan, it isno longer visible in the 2nd, supporting that this plateau is due to adsorbed species, such as HSO4- or SO42-. The same phenomenon was observed for various bath concentrations. Before the CV scan, the surface is saturated with adsorbed species which act as a barrier for the incorporation of Cu adatoms into the bulk Cu lattice. As a result, the surface activity shifts to a lower value when the potential goes slightly negative from OCP, leaving a plateau on the ring current curve. As the potential goes more negative and Cu deposition happens at a high rate, the adsorption is disrupted. During the 2nd scan the surface is not yet re-covered. Therefore, no plateau is observed in the 2nd scan. Various organic additives are used as suppressor or accelerator in Cu plating. These additives adsorb stronger on the Cu surface. Therefore, the width and shape of the ring current plateau are also affected by these additives [3].

Cellulose-zilvernanocomposieten hebben veelbelovende toepassingen in de voedingsindustrie als antibacteriële verpakking. Er is momenteel nog relatief weinig fundamenteel inzicht in de potentiële migratiemechanismen van nanodeeltjes uit deze (bio-)polymeermatrices. Omdat leaching of uitloging van zilvernanopartikels uit voedselcontactmaterialen nadelige effecten kan hebben op de gezondheid van de mens en het milieu, beoogt dit onderzoeksproject het verband tussen de uitgeloogde partikelconcentraties, groottedistributies en de externe uitloogcondities te achterhalen. Sferische zilvernanopartikels (~35 en ~70 nm) worden gesynthetiseerd en gedispergeerd in cellulose (standaard cellulose en gefunctionaliseerde cellulose). Vervolgens worden de gefabriceerde composietmodellen blootgesteld aan voedingssimulanten (10 en 20 % ethanol, 3 % azijnzuur en water), waarbij het externe medium geanalyseerd wordt met behulp van een nieuwe bepalingsmethode, gebaseerd op single particle inductief gekoppelde plasmamassaspectrometrie (SP-ICP-MS). Resultaten tonen aan dat de mate van uitloging bij 10 en 20 % ethanol weinig verschilt. Daarnaast zijn sterke aanwijzingen teruggevonden dat door het functionaliseren van cellulose minder partikels vrijgegeven worden. Bovendien blijkt dat kleine partikels meer uitlogen dan grote partikels vanwege hun relatief lage massa. De resultaten kunnen in de toekomst gebruikt worden om de hoeveelheid zilvernanopartikels waaraan mensen via voedselcontactmaterialen blootgesteld worden te kwantificeren.

The field of printed electronics is rapidly evolving, producing low cost applications with enhanced performances with transparent, stretchable properties and higher reliability. Due to the versatility of printed electronics, industry can consider the implementation of electronics in a way which was never possible before. However, a post-processing step to achieve conductive structures&mdash, known as sintering&mdash, limits the production ease and speed of printed electronics. This study addresses the issues related to fast sintering without scarifying important properties such as conductivity and surface roughness. A drop-on-demand inkjet printer is employed to deposit silver nanoparticle-based inks. The post-processing time of these inks is reduced by replacing the conventional oven sintering procedure with the state-of-the-art method, named near-infrared sintering. By doing so, the post-processing time shortens from 30&ndash, 60 min to 6&ndash, 8 s. Furthermore, the maximum substrate temperature during sintering is reduced from 200 &deg, C to 120 &deg, C. Based on the results of this study, one can conclude that near-infrared sintering is a ready-to-industrialize post-processing method for the production of printed electronics, capable of sintering inks at high speed, low temperature and with low complexity. Furthermore, it becomes clear that ink optimization plays an important role in processing inkjet printable inks, especially after being near-infrared sintered.