Bacterial spores in materials and equipment pose significant biosecurity risks, making effective disinfection crucial. This study evaluated Ortho-phthalaldehyde (OPA) and a quaternary ammonia-glutaraldehyde solution (AG) for inactivating spores of Bacillus thuringiensis (BT), B. cereus (BC), and two strains of B. velezensis (BV1 and BV2). Spores of BV1 and BT were treated with 22.5 mg/m3 OPA by dry fumigation or 1 mg/mL AG by spray for 20 min, according to the manufacturer\'s recommendation. As no sporicidal effect was observed, OPA was tested at 112.5 mg/m3 for 40 min, showing effectiveness for BT but not for BV1. Minimum bactericidal concentration (MBC) tests revealed higher MBC values for glutaraldehyde, prompting an overnight test with 112.5 mg/m3 OPA by dry fumigation and 50 mg/mL AG by spray, using formaldehyde as a control. AG reduced all Bacillus strains, but with limited sporicidal effect. OPA was sporicidal for BT and BV1 but not for BC and BV2, indicating a strain-dependent effect. Formaldehyde performed better overall but did not completely inactivate BV2 spores. Our findings suggest that OPA and AG have potential as formaldehyde replacements in wet disinfection procedures.

Despite the plethora of methods reported for fabricating ultraviolet (UV) shielding films using various UV absorbers to date, it remains a major challenge for the development of novel UV shielding films that simultaneously exhibit excellent transparency. In this work, a novel composite film (GA-x-CMC/PVA/PEI) is fabricated by integrating anionic carboxymethylcellulose (CMC), cationic polyethyleneimine (PEI), and polyvinyl alcohol (PVA) via electrostatic and hydrogen bond interactions and further cross-linking with glutaraldehyde (GA). Herein, PVA expands hydrogen bonding networks, reduces film haze, and enhances its mechanical strength. GA acts as a crosslinker in producing Schiff bases with PEI and acetals with CMC and PVA. The synthesized GA-x-CMC/PVA/PEI composite film possesses a notable amount of unsaturated -CH=N- bonds of Schiff base, resulting from the condensation of PEI and GA, which exhibit superior shielding efficiency against both UV-A and UV-B rays while maintaining exceptional transparency, visibility, and simultaneously enhancing mechanical properties and thermal stability. Notably, increasing the content of PEI leads to almost complete shielding of the entire UV spectrum (<400 nm) due to the increasing of the number of -CH=N- unsaturated bonds. Furthermore, the obtained film without any UV-shielding additives has exceptional mechanical properties, hydrophobicity, and antibacterial properties, rendering it a wide application prospect.

Effective continuous glucose monitoring solutions require consistent sensor performance over the lifetime of the device, a manageable variance between devices, and the capability of high volume, low cost production. Here we present a novel and microfabrication-compatible method of depositing and stabilizing enzyme layers on top of planar electrodes that can aid in the mass production of sensors while also improving their consistency. This work is focused on the fragile biorecognition layer as that has been a critical difficulty in the development of microfabricated sensors. We test this approach with glucose oxidase (GOx) and evaluate the sensor performance with amperometric measurements of in vitro glucose concentrations. Spincoating was used to deposit a uniform enzyme layer across a wafer, which was subsequently immobilized via glutaraldehyde vapor crosslinking and patterned via liftoff. This yielded an approximately 300 nm thick sensing layer which was applied to arrays of microfabricated platinum electrodes built on blank wafers. Taking advantage of their planar array format, measurements were then performed in high-throughput parallel instrumentation. Due to their thin structure, the coated electrodes exhibited subsecond stabilization times after the bias potential was applied. The deposited enzyme layers were measured to provide a sensitivity of 2.3 ± 0.2 μA mM-1 mm-2 with suitable saturation behavior and minimal performance shift observed over extended use. The same methodology was then demonstrated directly on top of wireless CMOS potentiostats to build a monolithic sensor with similar measured performance. This work demonstrates the effectiveness of the combination of spincoating and vapor stabilization processes for wafer scale enzymatic sensor functionalization and the potential for scalable fabrication of monolithic sensor-on-CMOS devices.

OBJECTIVE: To test the use of rainbow trout skin as a surgical mesh in abdominal hernioplasties in rats.
METHODS: The experiment involved 20 Wistar rats receiving implants of trout skin processed for disinfection in 0.5% glutaraldehyde and preserved in 100% glycerin. The animals were divided into four groups, divided at 7, 15, 30, and 90 days postoperatively. Clinical and infrared thermography evaluations were performed, and after euthanasia, assessments of adhesion formations and sample collection for histological evaluation were conducted.
RESULTS: The implant was observed to be intact, ensuring the integrity of the abdominal wall, support for the viscera, and normal mobility for the rats for up to 90 days. Low rates of clinical alterations were observed, with an intense inflammatory reaction up to day 7, chronic inflammation and the onset of angiogenesis at day 15, and a low inflammatory reaction with collagenous infiltrate and fibrosis at day 30. At day 90, the implants showed a collagenous and fibrotic infiltrate with a minimal inflammatory infiltrate.
CONCLUSIONS: The surgical mesh of trout skin performed well, making it a potential alternative for surgical procedures in muscle aponeurotic corrections in the abdominal wall.

In this study, a series of hydrogels were synthesized from chitosan(s) that was crosslinking with glutaraldehyde at different concentrations. Ascorbic acid in an acidic medium was used to facilitate non-covalent interactions. The chitosan(s) was obtained from shrimp cytoskeleton; while ascorbic acid was extracted from xoconostle juice. The hydrogel reaction was monitored by UV-vis spectroscopy (550 nm) to determine the reaction kinetics and reaction order at 60 °C. The hydrogels structures were characterized by NMR, FT-IR, HR-MS and SEM, while the degree of cross-linking was examined with TGA-DA. The extracellular matrices were obtained as stable hydrogels where reached maximum crosslinking was of 7 %, independent of glutaraldehyde quantity added. The rheological properties showed a behavior of weak gels and a dependence of crosslinking agent concentration on strength at different temperatures. The cytotoxicity assay showed that the gels had no adverse effects on cellular growth for all concentrations of glutaraldehyde.

The inferior hydrophobicity and mechanical properties of starch-based nanofibrous films significantly restrict their practical application. In view of this, this study prepared octenylsuccinylated starch-pullulan nanofibrous films using electrospinning and glutaraldehyde (GTA) gas-phase crosslinking. After GTA crosslinking, the starch-based nanofibrous films remained white, randomly oriented, smooth, and droplet-free. As the crosslinking time increased from 0 h to 24 h, the mean fibrous diameter augmented from 157.34 nm to 238.66 nm, and the water contact angle rose from 24.30° to 52.49°. Meanwhile, their tensile strength and thermal stability grew, and the mean pore area and elongation at break abated with changes in function groups. The crosslinked starch-based nanofibrous films exhibited an enhanced adsorption capacity for alcohols, ethers, esters, hydrocarbons, and N-compounds of oyster peptides. Correlation analysis shows that the adsorption capacity of the starch-based nanofibrous films was positively correlated with mean fibrous diameter and water contact angle and negatively correlated with mean pore area. These results provide a theoretical basis for the practical application of crosslinked starch-based nanofibrous film materials in deodorization.

BACKGROUND: The current study presents a novel and precise surgical technique for complete reconstruction of the aortic valve using glutaraldehyde-treated autologous pericardium in a patient with aortic valve disease and endocarditis. The technique aims to provide a more effective and reproducible method for aortic valve repair, with the goal of improving outcomes and quality of life for patients with aortic valve disease.
METHODS: A 35-year-old Iranian male with aortic valve disease and endocarditis underwent aortic valve reconstruction surgery. Preoperative echocardiography showed a degenerative aortic valve with severe regurgitation, reduced left ventricular ejection fraction, and specific aortic root dimensions. The surgical technique involved precise measurements and calculations to design the size and shape of the new aortic valve cusps using autologous pericardium, with the goal of optimizing coaptation and function. The surgeon calculated the intercommissural distance based on the aortic annulus diameter to determine cusp size and shape. He tailored the pericardial cusps to have a height equal to 80% of the coaptation margin length. Detailed suturing techniques were used to ensure proper alignment and coaptation of the new cusps. Intraoperative evaluation of the valve function using suction and transesophageal echocardiography showed good coaptation and minimal residual regurgitation. At the 3-year follow-up, the patient had a well-functioning aortic valve with only trivial leak and was in satisfactory clinical condition.
CONCLUSIONS: Glutaraldehyde-treated autologous pericardium is a validated leaflet alternative, and the causes of its failure are late annular dilatation and other technique breakdowns. Current evidence reveals that aortic valve reconstruction with glutaraldehyde-treated autologous pericardium is associated with many advantages with the potential to improve patient outcomes and quality of life. Further clinical studies are warranted to evaluate the long-term durability and efficacy of this approach.

This work aims to improve the post stabilty of reusable potassium iodide hydrogel dosimter. A reusable and low-cost radiochromic dosimeter containing a gel matrix of polyvinyl alcohol, potassium iodide dye, froctose as reducing agent and glutaraldehyde as cross-linking agent was developed for dose calibration in radiotherapy. The gel samples were exposed to different absorbed doses using a medical linear acceleration. UV-vis Spectrophotometry was utilized to investigate the changes in optical-properties of irradiated gels with regard to peak wavelength of 353 nm. The stability of the gel (one of the most limitation of using this dosimeter) was improved significantly by the addition of certain concentrations of dimethyl sulfoxide. The two-dimensional optical imaging system of charge-coupled-device (CCD) camera with a uniform RGB light-emitting-diode (LED) array source was used for diffusion coefficient purpose using two dimensional gel template. The value of diffusion coefficient reported is significant and highly reduced compared with other dosimeters reported in the literatures. Moreover, heating the improved gels to certain temperatures results in resetting their optical properties, which makes it possible to reuse for multiple times.

Heterogeneous biocatalysts were prepared by adsorbing T. lanuginosus lipase (TLL) onto uncalcined (SBAUC-TLL) and calcined (SBAC-TLL) SBA-15, using ammonium fluoride as a pore expander to facilitate TLL immobilization. At an enzyme load of 1 mg/g, high immobilization yields (>90 %) and recovered activities (>80 % for SBAUC-TLL and 70 % for SBAC-TLL) were achieved. When increasing the enzyme load to 5 mg/g, the immobilization yield of SBAUC-TLL was 80 %, and the recovered activity was 50 %, while SBAC-TLL had a yield of 100 % and a recovered activity of 36 %. Crosslinking with glutaraldehyde (GA) was conducted to improve stability (SBAUC-TLL-GA and SBAC-TLL-GA). Although SBAC-TLL-GA lost 25 % of initial activity after GA modifications, it exhibited the highest thermal (t1/2 = 5.7 h at 65 °C), when compared to SBAC-TLL (t1/2 = 12 min) and the soluble enzyme (t1/2 = 36 min), and operational stability (retained 100 % activity after 5 cycles). Both biocatalysts presented high storage stability since they retained 100 % of initial activity for 30 days. These results highlight SBA-15\'s potential as an enzyme support and the protocol\'s efficacy in enhancing stability, with implications for industrial applications in the food, chemical, and pharmaceutical sectors.

We present the synthesis of a cross-linking enzyme aggregate (CLEAS) of a peroxidase from Megathyrsus maximus (Guinea Grass) (GGP). The biocatalyst was produced using 50%v/v ethanol and 0.88%w/v glutaraldehyde for 1 h under stirring. The immobilization yield was 93.74% and the specific activity was 36.75 U mg-1. The biocatalyst surpassed by 61% the free enzyme activity at the optimal pH value (pH 6 for both preparations), becoming this increase in activity almost 10-fold at pH 9. GGP-CLEAS exhibited a higher thermal stability (2-4 folds) and was more stable towards hydrogen peroxide than the free enzyme (2-3 folds). GGP-CLEAS removes over 80% of 0.05 mM indigo carmine at pH 5, in the presence of 0.55 mM H2O2 after 60 min of reaction, a much higher value than when using the free enzyme. The operational stability showed a decrease of enzyme activity (over 60% in 4 cycles), very likely related to suicide inhibition.