Vacuum ammonia stripping from liquid digestate: Effects of pH, alkalinity, temperature, negative pressure and process optimization.

High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste. Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen, which has attracted a lot of attention in recent years. To investigate the parameter effects on the efficiency and mass transfer, five combination conditions (53 °C 15 kPa, 60 °C 20 kPa, 65 °C 25 kPa, 72 °C 35 kPa, and 81 °C 50 kPa) were conducted for ammonia stripping of sludge digestate. The results showed that 80% of ammonia nitrogen was stripped in 45 min for all experimental groups, but the ammonia transfer coefficient varied under different conditions, which increased with the rising of boiling point temperature, and reached the maximum value (39.0 mm/hr) at 81 °C 50 kPa. The ammonia nitrogen removal efficiency was more than 80% for 30 min vacuum stripping after adjusting the initial pH to above 9.5, and adjustment of the initial alkalinity also affects the pH value of liquid digestate. It was found that pH and alkalinity are the key factors influencing the ammonia nitrogen dissociation and removal efficiency, while temperature and vacuum mainly affect the ammonia nitrogen mass transfer and removal velocity. In terms of the mechanism of vacuum ammonia stripping, it underwent alkalinity destruction, pH enhancement, ammonia nitrogen dissociation, and free ammonia removal. In this study, two-stage experiments of alkalinity destruction and ammonia removal were also carried out, which showed that the two-stage configuration was beneficial for ammonia removal. It provides a theoretical basis and practical technology for the vacuum ammonia stripping from liquid digestate of organic solid waste.

Modeling and validation of purification of pharmaceutical compounds via hybrid processing of vacuum membrane distillation.

This study provides an in-depth examination of forecasting the concentration of pharmaceutical compounds utilizing the input features (coordinates) r and z through a range of machine learning models. Purification of pharmaceuticals via vacuum membrane distillation process was carried out and the model was developed for prediction of separation efficiency based on hybrid approach. Dataset was collected from mass transfer analysis of process to obtain concentration distribution in the feed side of membrane distillation and used it for machine learning models. The dataset has undergone preprocessing, which includes outlier detection using the Isolation Forest algorithm. Three regression models were used including polynomial regression (PR), k-nearest neighbors (KNN), and Tweedie regression (TWR). These models were further enhanced using the Bagging ensemble technique to improve prediction accuracy and reduce variance. Hyper-parameter optimization was conducted using the Multi-Verse Optimizer algorithm, which draws inspiration from cosmological concepts. The Bagging-KNN model had the highest predictive accuracy (R2 = 0.99923) on the test set, indicating exceptional precision. The Bagging-PR model displayed satisfactory performance, with a slightly reduced level of accuracy. In contrast, the Bagging-TWR model showcased the least accuracy among the three models. This research illustrates the effectiveness of incorporating bagging and advanced optimization methods for precise and dependable predictive modeling in complex datasets.

Nanopore ion sources deliver individual ions of amino acids and peptides directly into high vacuum.

Electrospray ionization is widely used to generate vapor phase ions for analysis by mass spectrometry in proteomics research. However, only a small fraction of the analyte enters the mass spectrometer due to losses that are fundamentally linked to the use of a background gas to stimulate the generation of ions from electrosprayed droplets. Here we report a nanopore ion source that delivers ions directly into high vacuum from aqueous solutions. The ion source comprises a pulled quartz pipette with a sub-100 nm opening. Ions escape an electrified meniscus by ion evaporation and travel along collisionless trajectories to the ion detector. We measure mass spectra of 16 different amino acid ions, post-translationally modified variants of glutathione, and the peptide angiotensin II, showing that these analytes can be emitted as desolvated ions. The emitted current is composed of ions rather than charged droplets, and more than 90% of the current can be recovered in a distant collector.

Pulsed vacuum drying of fruits, vegetables, and herbs: Principles, applications and future trends.

Pulsed vacuum drying (PVD) is a novel vacuum drying method that has demonstrated significant potential in improving energy efficiency and product quality in the drying of foods and agricultural products. The current work provides a comprehensive analysis of the latest advancements in PVD technology, including its historical development, fundamental principles, and mechanistic aspects. The impact of periodic pulsed pressure changes between vacuum and atmospheric pressure on heat and moisture transfer, as well as structural changes in foods at micro- and macro-scales, is thoroughly discussed. The article also highlights the influential drying parameters, the integration of novel auxiliary heaters, and the applications of PVD across various fruits, vegetables, and herbs. Furthermore, the review examines the current status and needs for mathematical modeling of PVD processes, identifying key challenges, research opportunities, and future trends for industrial application. The findings suggest that PVD not only enhances drying efficiency and reduces energy consumption but also preserves the nutritional value, color, and texture of dried products better than traditional methods. Future research should focus on optimizing process parameters and integrating advanced control systems to further improve the scalability and applicability of PVD technology in the food industry.

Effect of vacuum UV and UV-C treatment on degradation and ecotoxicity of tire wear microrubber leachates.

Tire wear microrubber particles (TWMP) are a major source of environmental contamination. Degradation of TWMP is slow and leachates contain toxic constituents including heavy metals, polycyclic aromatic hydrocarbons (PAHs) and organic additives. Few studies have addressed methods to mitigate the potential ecotoxicity of TWMP leachates. This study investigated the effects of UV-C (254 nm) and combined UV-C and vacuum UV (185 nm) treatment (VUV-UV-C) of TWMP leachates on degradation and ecotoxicity. VUV-UV-C treatment mitigated dissolved zinc and degraded the TWMP constituents fluoranthene, pyrene and benzo(a)pyrene by up to 90%, and the additives benzothiazole and phthalates by up to 70%. The potential ecotoxicity and genotoxicity of TWMP constituents were examined before and after UV treatment in bioassays with Escherichia coli, the luminescent bacterium Aliivibrio fischeri, the microalga Raphidocelis subcapitata and the crustacean Daphia magna. VUV-UV-C treatment decreased the potential ecotoxicity up to five-fold as indicated by changes in median effective concentrations (EC50). This was likely due to the formation of less toxic and less bioavailable transformation products. The VUV-UV-C treatment did not require the addition of oxidants or catalysts, and the study indicated a potential of VUV-UV-C as an advanced oxidation process to mitigate toxic compounds in TWMP leachates from urban or industrial sources.

Exploring versatile applications of a vacuum-assisted bone harvester in orthopedic surgery.

BACKGROUND: Orthopedic procedures often require removing bone or pathological tissue, with traditional methods involving instruments like curettes and rongeurs. However, these methods can be time-consuming and lead to increased blood loss. To mitigate these side effects, vacuum-assisted tools have been developed to aid in tissue removal. These devices enable surgeons to suction tissue without discarding it, potentially improving outcomes in conditions such as osteomyelitis or tumor removal while enabling collection of the material for downstream applications. Despite limited research, vacuum-assisted devices show promise beyond bone marrow harvesting. This study assesses infection and clearance rates, estimated blood loss, and total procedure time associated with the use of vacuum-assisted tissue removal, with a goal to understand if these devices can be used for tissue removal across a variety of pathologic conditions. METHODS: A retrospective cohort study was conducted on patients undergoing orthopedic procedures with the Avitus® Bone Harvester repurposed from its original design from December 1, 2021, to July 1, 2023. Procedures were categorized into oncology, and debridement for infection cases. Infection cases were further categorized into those secondary to trauma and those involving primary infections (osteomyelitis and periprosthetic joint infection). Clinical variables, including demographics, intraoperative details, complications, and follow-up, were reviewed. Statistical analysis included descriptive statistics computed with R Studio. RESULTS: The study included 44 patients, with debridement for infection cases being the most common (primary infection: 45.5%; infection secondary to trauma: 18.1%), followed by oncology cases (36.4%). In all oncology cases, a definitive diagnosis was established using the device, and no post-operative infections were reported. The infection clearance rate was 85.0% for primary infection cases and 50.0% for cases of infection following trauma. Across the entire cohort, the average blood loss was 314.52 mL (sd: 486.74), and the average total procedure time was 160.93 min (sd: 91.07). The overall reoperation rate was 47.7%, with an unplanned reoperation rate of 11.4%. CONCLUSION: The vacuum-assisted bone harvester was effectively utilized in a wide range of debridement and curettage procedures across diverse orthopedic surgeries. In oncology cases, the device enabled effective tissue removal with comparable recurrence rates, demonstrating its potential to minimize contamination while preserving tissue for accurate diagnoses. Additionally, a high rate of osteomyelitis eradication was observed in debridement for primary infection cases (85%). Despite the relatively high reoperation rate of 47.7%, it is crucial to interpret this figure within the context of the varied reasons for reoperation. Many of these reoperations were planned as part of a staged approach to treatment or were unrelated to the device's performance. It is crucial to acknowledge that isolating the device's contribution to these results can be difficult. The utilization of the device should be guided by considerations of cost-effectiveness and patient-specific risk factors.

Safety and efficacy of vacuum-assisted mini-percutaneous nephrolithotomy for the treatment of renal stone disease: an analysis of stone free status and postoperative infectious complications.

PURPOSE: Vacuum-assisted mini-percutaneous nephrolithotomy (vmPCNL) is being increasingly adopted due to its faster operating times and lower incidence of postoperative infectious complications (IC), however, studies have been limited by small sample sizes. We hypothesize that vmPCNL is an efficacious treatment for renal stone disease with acceptable stone-free rates (SFR) and low incidence of IC. The objectives of this study were to measure SFR three months after surgery, determine the factors influencing SFR, and determine the rates of postoperative IC after vmPCNL. MATERIALS AND METHODS: Seven hundred and sixty seven patients underwent vmPCNL for the treatment of renal stones > 20 mm at a single institution. Patients underwent postoperative computed tomography at three months to assess SFR. Postoperative fever and SIRS/Sepsis were recorded for individual patients. Multivariate logistics regression was performed to assess predictors of SFR. RESULTS: The SFR was found to be 73.7% at three months. Stone burden (OR 0.39, 95% CI [0.33-0.46]) and age (OR 1.03, 95% CI [1.01-1.04]) emerged as statistically significant predictors of SFR on multivariate analysis. 5.5% of patients experienced postoperative fever, while 2.9% experienced SIRS/Sepsis. CONCLUSIONS: This is the largest continuous cohort of patients to undergo vmPCNL for stone disease and demonstrates that vmPCNL is safe and efficacious, with an SFR of 74% at three months. The incidence of postoperative fever and SIRS/Sepsis is 5.5% and 2.9% respectively. Further randomized studies with large sample sizes are required to ascertain the rates of these complications in comparison to conventional approaches.

Can vacuum-formed retainers maintain arch dimensions and alignment compared to Hawley and fixed bonded retainers after treatment with fixed appliances? A systematic review and meta-analysis.

BACKGROUND: Different types of retention appliances have been proposed over the years, but their effectiveness in maintaining arch dimensions and alignment after orthodontic treatment is still unclear. AIM: To assess the efficacy of vacuum-formed retainers (VFRs) in preserving arch widths, arch length, and anterior alignment in maxillary and mandibular arches, compared to removable Hawley retainers (HRs) or fixed bonded retainers (FBRs). Search methods: unrestricted literature search of five major databases up to March 2024. SELECTION CRITERIA: randomized/non-randomized clinical studies comparing VFRs to removable HRs or FBRs. DATA COLLECTION AND ANALYSIS: after duplicate study selection, data extraction, and risk of bias assessment, random effects meta-analyses of standardized mean differences and their 95% confidence intervals were performed, followed by meta-regressions, sensitivity analyses, and assessment of the quality of evidence with GRADE. RESULTS: Twenty-two prospective studies (4 non-randomized and 18 randomized controlled trials) involving 1797 patients (mean age 17.01 years, 38.3% males) were included. No significant differences were found in the intercanine width, intermolar width, and arch length between VFRs and HRs, in both arches (P > 0.05). However, VFRs were statistically more effective than HRs in terms of Little's irregularity scores (LII) in the maxilla (eight studies; SMD = -0.42; 95% CI: -1.03 to -0.09; P = 0.02; I2 = 73.4%) but not in the mandible (P = 0.12). No significant differences were reported for all considered outcomes between VFRs and FBRs in in both arches (P > 0.05), except for lower LII, where VFRs were significantly less efficient (eight studies; SMD = 1.49; 95% CI = 0.26-2.7; P = 0.02; I2 = 93%). Follow-up times, risk of bias, and wire type (of FBRs) did not show statistically significant effects on outcome variables. Sensitivity analyses showed robustness of the findings for including non-randomized and postretention studies. The certainty in these estimates was from moderate to low due to the risk of bias and inconsistency. CONCLUSIONS: Low to moderate quality evidence indicates that VFRs are as effective as HRs in maintaining arch widths, length, and alignment. Low-quality evidence found similar efficacy between VFRs and FBRs, with FBRs being statistically more effective at maintaining lower arch alignment, but the difference was not clinically significant. REGISTRATION: PROSPERO registration (CRD42024518433).

Vacuum-Based Agroinfiltration for Transient Gene Expression in Arabidopsis Seedlings.

Agrobacterium-mediated transient expression is a flexible and efficient technique for introducing genes into plants, allowing for rapid and temporary gene expression. Agroinfiltration of Arabidopsis seedlings is a newly developed Agrobacterium-based transient expression system. The expression of target genes and the localization of relevant proteins can be observed within 3 days using this method. In this chapter, we present the detailed protocol for transient transformation in Arabidopsis thaliana seedlings utilizing vacuum infiltration of Agrobacterium. This procedure enables rapid and temporary gene expression by introducing exogenous DNA into Arabidopsis seedlings, particularly in easily accessible tissues such as cotyledons. This protocol provides a detailed description of experimental procedures, including Arabidopsis seedlings cultivation, the preparation of Agrobacterium suspensions, and subsequent steps leading to confocal microscope observation. Through this protocol, researchers can efficiently investigate gene function and subcellular localization in Arabidopsis cotyledons within 8 days in total.

Improved thermal stabilization of VSV-vector with enhanced vacuum drying in pullulan and trehalose-based films.

One major limitation of effective vaccine delivery is its dependency on a robust cold chain infrastructure. While Vesicular stomatitis virus (VSV) has been demonstrated to be an effective viral vaccine vector for diseases including Ebola, its -70 °C storage requirement is a significant limitation for accessing disadvantaged locations and populations. Previous work has shown thermal stabilization of viral vaccines with a combination of pullulan and trehalose (PT) dried films. To improve the thermal stability of VSV, we optimized PT formulation concentrations and components, as well as drying methodology with enhanced vacuum drying. When formulated in PT films, VSV can be stored for 32 weeks at 4 °C with less than 2 log PFU loss, at 25 °C with 2.5 log PFU loss, and at 37 °C with 3.1 log PFU loss. These results demonstrate a significant advancement in VSV thermal stabilization, decreasing the cold chain requirements for VSV vectored vaccines.

Effects of deep, air and vacuum frying on oyster quality and protein-mediated mechanism analysis via TMT quantitative proteomics.

Fried oyster is a popular aquatic food product in East Asia, but nutrient loss during thermal processing become a significant concern. The goal of this research was to examine the impact of distinct frying techniques, including deep frying (DF), air frying (AF), and vacuum frying (VF), on the nutritional, textural and flavor characteristics of oysters. The VF method demonstrated superior retention of beneficial properties and flavor, and reduced protein and lipid oxidation compared to the DF and AF methods. Furthermore, proteomic analysis of oysters was attempted to explain the molecular mechanisms governing the influence of key differential proteins. 20 major differential proteins, including actin-2 protein, tryptophan 2,3-dioxygenase and 1-alph, involved in oyster protein oxidation were identified, annotated and analyzed to elucidate their influence mechanisms. This research provides a deeper understanding of intricate interactions between frying techniques and oyster biochemistry, which offers valuable implications for enhancing food quality in seafood industry.

Vacuum impregnation: Effect on food quality, application and use of novel techniques for improving its efficiency.

Vacuum Impregnation (VI) act as promising method for rapidly introducing specific concentration solutions into food matrices using a hydrodynamic mechanism and deformation phenomenon to attain a product with specific tailored functional quality characteristics. VI facilitates rapid introduction of specific solutions into the food matrices. This technique allows efficient incorporation of bioactive compounds and nutritional components, meeting the rising consumer demand for functional foods. Furthermore, VI when combined with non-thermal techniques, opens up new avenues for preserving higher quality attributes and enhancing antimicrobial effects. The unique ability of VI to rapidly infuse specific solutions into food matrices, combined with the advantages of non-thermal processes, addresses the growing consumer demand for products enriched with bioactive ingredients. Hence, the present review aims to explore the potential impact of VI, coupled with novel techniques, on food quality, its practical applications, and the enhancement of process efficiency for large-scale industrial production.

Optimizing particle size segregation in vacuum drum-based capsule filling machines: A stirrer design approach.

This study investigates particle size segregation within the powder chamber of a vacuum drum-based capsule filling machine using various stirrer types and proposing novel designs to mitigate segregation. The stirrer is essential to the process, ensuring uniform density during volume-based filling. Three lactose grades, comprising 10% fine, 80% medium, and 10% coarse particles, were used, with tracer particles replacing fine or coarse particles, respectively. Dosages were collected over time for a line-array of five bores, and tracer concentrations were analysed using UV-Vis spectrophotometry. By visual assessments and stagnant zone observations particle segregation was evaluated and quantified by normalised tracer concentrations. Both standard and modified stirrers were examined under the same conditions. Stirrer type significantly influenced particle segregation, with the "spike" standard stirrer yielding the highest segregation, while the modified "3-wirem" and "coreless 3-wirem" stirrers exhibited superior performance, minimizing differences between fine and coarse particle concentrations and eliminating stagnant zones. These findings highlight promising prospects for further analysing the "3-wirem" and "coreless 3-wirem" stirrers. In that respect additional variables such as stirrer speed, rotation direction, and level of vacuum, need to be considered. Stirrer design significantly impacts vacuum drum-based capsule filling machine performance, ensuring reliable pharmaceutical capsule filling. This study offers insights into optimizing the industrial process.

Tailor-made packaging strategies of fresh pork belly with different fat content: Enhancing shelf life while minimizing environmental impact.

Pork belly is a meat cut valued for its rich flavour and texture, attributed to its high fat content, which also makes it susceptible to oxidation. Therefore, meat producers and processors must carefully select packaging options to maximise shelf life while meeting consumer preferences. This study aimed to develop customised packaging strategies for sliced pork belly with varying fat content to extend shelf life while minimizing environmental impact. The research compared three packaging solutions: modified atmosphere packaging (MAP1: 70:30% O2:CO2, MAP2: 30:40:30% O2:CO2:N2) and vacuum skin packaging (VSP) for pork bellies with low (LF: 16.07 ± 1.87%), medium (MF: 37.39 ± 4.41%), and high fat content (HF: 57.57 ± 2.36%). Samples packaged in VSP exhibited the longest shelf life (13-14 days) with lower purge and reduced fat and colour oxidation compared to MAP-packaged samples for all studied belly types. Nonetheless, the impact of MAP on shelf life depended on the belly type. HF bellies, with lower proportions of unsaturated fatty acids, showed less purge, and greater colour and fat stability, resulting in a longer shelf life compared to LF and MF bellies. LF and MF bellies in MAP2 showed the shortest shelf life (around 6 days), followed by LF and MF in MAP1 (around 7-8 days). Life Cycle Assessment indicated VSP generally as the most environmentally favourable option for LF and MF bellies, whereas for HF bellies, the choice among the three packaging solutions depended on the specific impact category under consideration.

Tuning the morphology and textural properties of ZSM-5 additive for co-cracking of waste plastics with vacuum gas oil to light olefins.

Typical cracking catalysts, called equilibrium catalyst (E-Cat) are ultra-stable Y (USY) zeolite often used with 15% commercial ZSM-5 zeolite additive (ZSM-5(COM)) to boost olefin yield. In this study, similar additive zeolites with different pore sizes and acidic character were synthesized by rapid ageing of precursor solution and used in the co-cracking of low-density polyethylene (LDPE) and heavy vacuum gas oil (HVGO). Three ZSM-5 zeolites additives with Si/Al ratio 25 (ZSM-5(25)), 50 (ZSM-5(50)) and 75 (ZSM-5(75)) were synthesized and combined with E-Cat to form E-Cat/ZSM-5(25), E-Cat/ZSM-5(50) and E-Cat/ZSM-5(75) respectively. The E-Cat/ZSM-5(50) has slightly better endothermic conversion (cracking) of a mixture of dissolved LDPE and HVGO into H2, C1 to C4 gases and C2-C4 light olefins (total conversion of E-Cat 80.0%, E-Cat/ZSM-5(COM) 75.0% and E-Cat/ZSM-5(50) 83.7% respectively), with different gas, liquid and coke distributions. The E-Cat/ZSM-5(75) has 81% conversion, and highest yield of light olefins (38.4%). Structural (surface area, pore size) and chemical (acid sites) characteristics of the synthetized ZSM-5(75) zeolite explain the observed higher light olefin selectivity by different and competing catalytic routes. The ZSM-5(75) has demonstrated to be a good zeolite additive for converting dissolved plastic in HVGO into light olefins.

Microbore-based vacuum jacketed liquid chromatography for fast, efficient and sustainable high throughput bioanalysis.

Extra-column band broadening can significantly reduce the performance of rapid ultra-high performance liquid chromatography-MS-based methods (UHPLC-MS). However, as we show here, UHPLC-MS/MS methods on short 2.1 mm i.d. columns can be optimized to reduce band broadening by simple procedures such as dispensing with the solvent divert valves placed between the column and the MS source. Vacuum jacketed columns have previously been shown to provide superior performance to conventional UHPLC-MS/MS by reducing on and post column band broadening. Here we have compared the optimized "direct" UHPLC approach for the high throughput (HT) bioanalysis of drugs and metabolites in biofluids such as urine and blood plasma with vacuum jacketed chromatography (VJC), using columns of the same geometry and packed with the same stationary phases. This study demonstrates that the performance of VJC was still superior to the direct UHPLC-MS/MS methods for rapid "generic" bioanalysis using gradient times of 0.25 to 5 min. Further investigations using microbore VJC-MS/MS, with 1 mm i.d. columns, for bioanalysis of the same biofluid samples showed that this format offers great promise for HT "discovery" drug and metabolite analysis/profiling. In addition the reduction of solvent use, by up to 90 % for methods when using microbore columns, can significantly contribute to improved sustainability and reducing costs per analysis.

Vacuum freeze drying combined with catalytic infrared drying to improve the aroma quality of chives: Potential mechanisms of their formation.

This study aimed to investigate the effect of vacuum freeze drying combined with catalytic infrared drying (FD-CIRD) process on aromas, free amino acids, reducing sugars and free fatty acids in chive leaves and stems. Gas chromatography-mass spectrometry combined with multivariate data analysis revealed that dipropyl disulfide was the key aroma that distinguished the differences between chive leaves and stems. The key aromas benzeneacetaldehyde, decanal and 1-octen-3-ol enhanced FD-CIRD chive leaves and stems aromas. The free amino acid content was highest at FD-CIRD stage in all samples except for the control (FD), while the reducing sugar content was lowest. The content of unsaturated fatty acids gradually decreased at FD stage and increased at FD-CIRD stage. Additionally, correlation analysis revealed that phenylalanine was a potential precursor of benzacetenealdehyde, oleic and linolenic acids were potential precursors of decanal and 1-octen-3-ol. Therefore, FD-CIRD technique helps to improve the sensory profile of dried chives.

Phthalate migration potential in vacuum-packed fish.

Phthalates or phthalate esters (PAEs) have become a serious concern due to their toxicity and risks of migration from contact materials to food matrices and the environment. The aim of this study is to monitor the possible migration potential of PAEs in pelagic fish stored in vacuum packaging depending on the storage time and to determine the polyethylene polymers. In order to achieve this goal, sea bass (Dicentrarchus labrax) and anchovy fish (Engraulis encrasicolus) were randomly packaged in vacuum bags and then stored for 90 days. Phthalate content was determined by GC/MS technique in the muscle tissue of each fish species at certain periods (0, 30, and 90 days) of storage, and on the first day in the packaging material and fish meat. As a result of the analysis performed in µ-Raman spectroscopy, no microplastics were detected in both fish species' meats. FTIR spectroscopy results of the packaging material determined nylon in the chemical content of the packaging material before processing. It has been determined that the chemical composition of the packaging used in the vacuum packaging process is affected by the temperature, depending on the storage period, and different polymer types are formed in the processed package material. It was determined that the dominant PAE homologues were Di-n-pentyl phthalate (DPENP) in both fish meat and Di-(2-ethylhexyl)-phthalate (DEHP) in the package. However, during storage, Dibutylphthalate (DBP) became dominant in anchovies and DPENP became dominant in sea bass, differing according to fish species and storage time.

Case Study: Compatibility Testing of Pre-Filled Syringe Stopper Technology with Vaporized Hydrogen Peroxide Terminal Sterilization Process.

STERIS and W.L. GORE collaborated on a case study testing the compatibility of a new prefilled syringe plunger design with VHP terminal sterilization. VHP chamber conditions require deep vacuum pulsing, which may represent challenges to prefilled syringe container integrity. The growing industry trend toward VHP sterilization is driven by the FDA search for alternative sterilization methods to EO and the recent publication of a VHP specific process standard. The purpose of the study is to test and report compatibility of the new 0.5 mL GORE IMPROJECT plunger, a silicone free syringe solution for ophthalmic application, with VHP sterilization. Various challenges have been reported when using conventional, siliconized, prefilled syringe systems for intravitreal injections such as subvisible particles, inflammation, silicone floaters, and intraocular pressure increases. The GORE plunger eliminates the need for silicone oil as a lubricant on the plunger and barrel, while meeting strict container closure and terminal sterilization requirements of ophthalmic applications. This case study presents successful results of deep vacuum VHP terminal sterilization process compatibility with the GORE plunger design and material composition. Test results include primary container integrity, stopper off-gassing/ingress, and visual inspection. Principles of VHP vacuum sterilization process, test cycle configuration, and its main parameters are presented.

Cape Gooseberry (Physalis peruviana L.) Volatile Compounds Determination by Vacuum-Assisted Sorbent Extraction (VASE)-Selected Aspects.

Vacuum-Assisted Sorbent Extraction (VASE) is a novel extraction technique that uses vacuum to facilitate the transfer of volatile compounds from the matrix to the sorbent. This technique was explored for extraction of volatiles from cape gooseberry fruit, for both qualitative and quantitative analyses. Selected extraction parameters were tested: sample size, extraction temperature and time, influence of tissue disintegration on release of volatiles, and also addition of Ag+1 ions in the form of AgNO3 to stop enzymatic formation of volatile compounds. For selected conditions (10 g sample, extraction for 30 min. at 40 °C of volatiles from blended fruit) quantitative aspects were explored. Twenty-two compounds of cape gooseberry were tested. The method was characterized with a very good linearity in a range of 10-5000 µg/kg and good reproducibility. The experiments proved the usefulness of VASE in both volatile profiling and quantitative analyses of cape gooseberry and in prospective other fruit.