Enzyme catalysis powered micro/nanomotors for biomedical applications

With recent developments in the field of autonomous motion for artificial systems, many researchers are focusing on their biomedical application for active and targeted delivery. In this context, enzyme powered motors are at the forefront since they can utilize physiologically relevant fuels as their substrate and carry out catalytic reactions to power motion under in vivo conditions. This review focuses on the design and fabrication of enzyme powered motors together with their propulsion mechanism by using fuels present in biological environments. In addition, the recent advances in the field of enzyme powered motors for biomedical applications have been discussed together with the parameters that need to be considered for designing such systems. We believe that this review will provide insights and better understanding for the development of next generation biomedical technologies based on enzyme powered motors

Rare earth 4-hydroxycinnamate compounds as carbon dioxide corrosion inhibitors for steel in sodium chloride solution

A series of rare earth 4-hydroxycinnamate compounds including Ce(4OHCin)3, La(4OHCin)3, and Pr(4OHCin)3 has been synthesized and evaluated as novel inhibitors for carbon dioxide corrosion of steel in CO2-saturated sodium chloride solutions. Electrochemical measurements and surface analysis have shown that these REM(4OHCin)3 compounds effectively inhibited CO2 corrosion by forming protective inhibiting deposits that shut down the active electrochemical corrosion sites on the steel surface. Inhibition efficiency was found to increase in the order Ce(4OHCin)3 < La(4OHCin)3 < Pr(4OHCin)3 and with increase in inhibitor concentration up to 0.63 mM. Detailed insights into corrosion inhibition mechanism of these compounds in carbon dioxide environment are also provided

Comparative Evaluation of Masson's Trichrome and Picrosirius Red Staining for Digital Collagen Quantification Using ImageJ in Rabbit Wound Healing Research

The therapeutic potential of Pluronic F127 (PF127) hydrogel loaded with adipose-derived stromal vascular fraction (AdSVF), mesenchymal stem cells (AdMSC), and conditioned media (AdMSC-CM) for repairing full-thickness skin wounds was evaluated using a rabbit model. The rabbits were randomly divided into eight groups with six animals each and treatment was given as per the predetermined protocol (3 doses at one-week interval): Group A (Control), Group B (AdSVF), Group C (AdMSC), Group D (AdMSC-CM), Group E (PF127), Group F (AdSVF + PF127), Group G (AdMSC + PF127), and Group H (AdMSC-CM + PF127). Skin tissue samples were collected from the healing wounds on day 28 for staining and collagen quantification. Collagen density (Area %) was quantified using tissue sections stained with Masson's Trichrome (MT) and Picrosirius Red (PSR) stain using the Colour Deconvolution plugin of ImageJ and RGB stack method, respectively. These techniques function based on separating different colour channels in the stained tissue sections to isolate the collagen fibers and then quantifying them through thresholding and image analysis. Across the treatment groups, both staining methods generally showed a trend of increased collagen density compared to the control group. For most groups, PSR staining consistently indicated slightly lower collagen densities than MT staining. However, the overall trends were similar in both staining. The comparison between PSR and MT staining methods revealed that both techniques effectively assess collagen density in healing wounds. However, there were subtle differences in the absolute values obtained, with PSR staining tending to yield slightly lower collagen density measurements than MT. These differences can be attributed to the distinct mechanisms of these staining methods. Therefore, both staining methods can digitally quantify collagen density in wound healing research

The behaviour of praseodymium 4-hydroxycinnamate as an inhibitor for carbon dioxide corrosion and oxygen corrosion of steel in NaCl solutions

Praseodymium 4-hydroxycinnamate (Pr(4OHCin)3) was investigated as a novel corrosion inhibitor for steel in NaCl solutions, and found to be effective at inhibiting corrosion in both CO2-containing and naturally-aerated systems. Surface analysis results suggest that the corrosion inhibition ability of Pr(4OHCin)3 in the naturally-aerated corrosion system could be attributed to the formation of a continuous protective film. For the CO2-containing system, the corrosion inhibition efficiency of Pr(4OHCin)3 was predominantly because of formation of protective inhibiting deposits at the active electrochemical corrosion sites, in addition to a thinner surface film deposit. © 2013