Anti-Metalloprotease P-I Single-Domain Antibodies: Tools for Next-Generation Snakebite Antivenoms.

In order to address the global antivenom crisis, novel antivenoms need to present high therapeutic efficacy, broad neutralization ability against systemic and local damage, sufficient safety, and cost-effectiveness. Due to biological characteristics of camelid single-domain antibodies (VHH) such as high affinity, their ability to penetrate dense tissues, and facility for genetic manipulation, their application in antivenoms has expanded considerably. VHHs that are active against the metalloprotease BjussuMP-II from the snake Bothrops jararacussu were selected. After isolation of BjussuMP-II, a camelid was immunized with the purified toxin in order to construct the recombinant phage library. Following a round of biopanning, 52% of the selected clones were able to recognize BjussuMP-II in an ELISA assay. After sequencing, seven sequence profiles were identified. One selected clone (VHH61) showed cross-reactivity to B. brazili venom, but did not recognize the Crotalus and Lachesis genera, indicating specificity for the Bothrops genus. Through in vitro tests, the capacity to neutralize the toxicity triggered by BjussuMP-II was observed. Circular dichroism spectroscopy indicated a robust secondary structure for VHH61, and the calculated melting temperature (T M) for the clone was 56.4°C. In silico analysis, through molecular docking of anti-BjussuMP-II VHHs with metalloprotease, revealed their potential interaction with amino acids present in regions critical for the toxin's conformation and stability. The findings suggest that anti-BjussuMP-II VHHs may be beneficial in the development of next-generation antivenoms.

KOH-super activated carbon from biomass waste: Insights into the paracetamol adsorption mechanism and thermal regeneration cycles.

A super activated carbon (SAC) was produced by KOH-activation of a biomass waste for paracetamol (PCT) adsorption from aqueous solution and for adsorption-thermal regeneration cycles. The SAC and the regenerated SAC after five adsorption-regeneration cycles (RSAC-5th) were fully characterized by several techniques. The N2 physisorption showed that the SBET values of the SAC and RSAC-5th are remarkably different, being 2794 m² g-1 and 889 m² g-1, respectively. The XPS analysis demonstrated that the SAC surface is composed by oxygen containing-groups, whilst the RSAC-5th also presents nitrogen ones, provenient from the PCT molecules. The adsorption studies revealed that the maximum adsorption capacity (Qm) for the SAC (356.22 mg g-1) is higher than that for RSAC-5th (113.69 mg g-1). Also, the results demonstrated that the PCT adsorption is governed by both physisorption and chemisorption and the ab initio calculations showed the chemisorption mainly occurs in carboxylic groups.

Stevia residue as new precursor of CO2-activated carbon: Optimization of preparation condition and adsorption study of triclosan.

The present work reports the preparation of CO2-activated carbon (AC) using Stevia rebaudiana (Bertoni) residue as a new carbon precursor. The experimental parameters were optimized via chemometrics tools to obtain an AC with high BET surface area (SBET). The found optimum condition was: activation temperature of 900 °C, CO2 flow of 165 cm3 g-1 and activation time of 60 min, providing an ACop with SBET of 874 m2 g-1. The ACop was characterized from several analytical techniques, which showed that it has heterogeneous morphology features and different surface chemical groups, predominating the acidic character. The adsorption performance of ACop for triclosan (TCS) removal from solution was investigated by kinetic, equilibrium and thermodynamic studies. The results showed that TCS adsorption process onto ACop is spontaneous and endothermic, wherein the mechanism occurs by different steps, which equally play important roles. Additionally, the monolayer adsorption capacity (Qm) was found to be 117.00 mg g-1.