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The objective of this research was to evaluate the anaerobic co-digestion of guinea pig manure (CY) with Andean agricultural residues such as amaranth (AM), quinoa (QU) and wheat (TR) in batch biodigesters under mesophilic conditions (37⁰C) for 40 days. As microbial inoculum, sewage treatment sludge was used in two inoculum/substrate ratios (ISR of 1 and 2). In terms of methane production, the best results occurred in the treatments that contained AM and QU as co-substrate and an ISR of 2. Thus, the highest methane production occurred in the CY:AM biodigesters (25:75) and CY:QU (25:75) with 341.86 mlCH4/g VS and 341.05 mlCH4/g VS, respectively. On the other hand, the results showed that methane production with an ISR of 2 was more feasible for guinea pig waste, where the methane fraction of the biogas generated was in a range of 57 and 69%. The kinetics of methane production from these raw materials was studied using five kinetic models: modified Gompertz, logistic equation, transfer, cone, and Richards. The cone model was the one that best adjusted the experimental values ​​with those observed with an r2 of 0.999 and an RMSE of 1.16 mlCH4/g VS. Finally, the highest biodegradability was obtained in the CY-AM biodigesters (25:75) with 67.92%.

The objective of this work was to develop a simple spectrophotometric method for determining antibiotic florfenicol in Eudragit nanocapsules. Regression curve of the method is linear in a concentration range of 80 – 480 μg/mL (correlation coefficient, 0.9998) at a selected wavelength of 270 nm. The limits of detection and quantification are 0.4 μg/mL and 1.2 μg/mL, respectively. The developed method demonstrated good inter-day and intra-day precision with RSD < 2. The percentage recovery of florfenicol was within 99.56 – 99.90%. In conclusion, the proposed method is specific, reproducible, accurate, and robust for the determination of florfenicol in Eudragit nanocapsules with detection at 270 nm in 95% confidence interval.

The objective of this work was to develop and characterise an amikacin sulfate loaded emulgel to be used as a co-adjuvant treatment for mycetoma caused by principal agents Actinomadura madurae and Nocardia brasiliensis. Development of the amikacin sulfate emulgel was conducted in 3 stages: (1) formulation of the emulsion containing amikacin; (2) selection of the proportion of pluronic F-127 necessary to form a gel; and (3) formation of the emulgel. The emulgel was characterised by the values of pH, relative density, accelerated stability, viscosity, extensibility, adhesiveness, cumulative amount of amikacin, and skin permeation (kp and flux). The proportion of emulsifiers in the emulsion was 10% and 0.77% (w/w) of amikacin, and the emulsion was stable when subjected to the centrifugal test. Agel with 30% pluronic F-127 and an average adhesiveness of 2.7 mJ was used to form the emulgel. The formulated amikacin sulfate emulgel has the following properties: pH 5.5; relative density, 0.907; accelerated stability (centrifugation); extensibility. 923.72 mm2; adhesiveness, 1.27 mJ; cumulative amikacin (within 24 h), 34.13%; F = 105 μg/cm2/h; kp = 0.016 cm/h; and tLag = 14.75 h. The emulgel formulation contains 0.77% of amikacin and demonstrates appropriate technical characteristics to be used as a complement to systemic administration for the treatment of mycetoma.

The aim of this work was to develop and characterize biodegradable polymeric microneedle arrays loaded with (i) losartan potassium powder and (ii) nanoparticles loaded with losartan potassium dispersed in polymeric matrix (starch/gelatin) as innovative pharmaceutical forms intended to be used for blood pressure control. The lecithin/gelatin nanoparticles were prepared by desolvation method. The independent variables were lecithin/gelatin amount and stirring speed while particle size, PDI (polydispersity index), and entrapment efficiency were the dependent variables studied. The optimized nanoparticle formulation was also characterized in terms of ζ potential and morphology. The mold of microneedle manufacture was created using a 3D printer by molding, and the microneedle arrays were prepared by micromolding method. The independent variables were starch/gelatin amount and drug form while fracture force, bioadhesion, and post-wetting bioadhesion were the dependent variables evaluated. The optimized microneedle array formulations were also characterized and evaluated in terms of morphology, release profiles, and in vitro losartan skin permeation studies. The optimized nanoparticle formulation was of 170.3 ± 3.1 nm of size, with 0.201 ± 0.013 of PDI, 40.45 ± 2.27% of entrapment efficiency, and − 32.9 ± 0.8 mV of ζ potential. The mold had an array of 25 microneedles with a height of 1.5 mm each. The optimized microneedle arrays were successful in terms of fracture force with a value of 408.3 ± 6.1 gf for MP and 320.2 ± 17.4 gf for MN. The results of in vitro skin permeation studies indicated that therapeutic losartan concentrations can be reached by using a microneedle array of 49 cm2 for MP and 13 cm2 for MN. The optimal formulation of the microneedle array with nanoparticles constitutes the most suitable option for skin losartan delivery.

The aim of this work was to optimize unidirectional buccal patches loaded with metoprolol (MT-MBPs) to provide adequate mucoadhesive and water uptake properties as well as controlled drug release for the effective treatment of different cardiovascular diseases. The patches were prepared layer-by-layer using the solvent casting method. A central composite design was employed to statistically optimize the formulation variables. Chitosan and Pluronic® F-127 (poloxamer 407) concentrations were chosen as the independent variables, while ex vivo mucoadhesive force, ex vivo residence time, in vitro water uptake (%), and in vitro drug release (%) were to be considered the dependent variables. The optimized formulation was also characterized and evaluated in terms of morphology, thermal behavior, tensile strength, elongation at break, and ex vivo drug permeation. The optimized MT-MBPs were successful in terms of mucoadhesive force (3.58 ± 0.62 N), residence time (342.67 ± 17.21 min), and water uptake at 1 h (24.53 ± 3.62%). A controlled drug release was obtained for 8 h. Thermal and morphologic analyses demonstrated that metoprolol was homogeneously distributed throughout the microporous chitosan-based polymer matrix. Furthermore, the MT-MBPs exhibited a tensile strength of 3.76 ± 0.55 N/mm2 and an elongation at break of 36.52 ± 13.88%. The results of ex vivo permeation through pig buccal mucosa indicated that therapeutic metoprolol concentrations can be reached by using a patch of 5.62 cm2. Optimal composition of the MT-MBPs included 2.9% (w/v) and 2.6% (w/v) of chitosan and Pluronic® F-127, respectively, which constitutes the most suitable makeup for metoprolol buccal delivery.

This paper experimentally demonstrates the viability of Lamb waves generation and detection in metallic plates using ultrasonic air-coupled concave array transducers. For this purpose, a self-developed air-coupled Lamb wave NDT system has been used in three different metallic plates, such as stainless steel, copper and brass. First, pure copper plates were used to calibrate the measuring system and then other tests were performed in 304 stainless steel and CW508L brass. The obtained Lamb waves confirm the theoretical values, both in the phase velocity and in the group velocity measurements. In addition, a complete study of the errors in the measurements is also provided.

A rapid and reliable method of dolphinfish species identification was designed based on PCR amplification of diagnostic DNA fragments from the mitochondrial cytochrome b gene. It consisted in a tetraplex reaction producing a positive control amplicon and species-specific fragments in Coryphaena hippurus and C. equiselis. It was successfully tested in specimens of known identity and in nominal C. hippurus samples among which two C. equiselis were discovered. This approach has significant advantages over other molecular species identification methods and may help in determining species composition of mixed catches, and in forensic and food control applications of dolphinfish specimens or products.

The spectral study of an optical modulator based on the frustrated total internal reflection is presented under static and dynamic conditions. An optical modulator based on macroscopic moving parts makes spectrometers voluminous and has low compactness. The use of static or quasi-static optical modulators, such as the one proposed in this paper, avoids these problems. The study under static conditions reveals that the modulator equalises the spectral emittance of a black body. The modulation efficiency is defined by comparing the modulator with an ideal square chopper. Study under dynamic conditions reveals spectral criteria that must be met in the design of the mechanical system of the modulator to shift the maximum value of the modulation efficiency to the desired wavelength.