Optimizing the lyophilization of Lumbricus terrestris erythrocruorin.

Haemorrhagic shock is a leading cause of death worldwide. Blood transfusions can be used to treat patients suffering severe blood loss but donated red blood cells (RBCs) have several limitations that limit their availability and use. To solve the problems associated with donated RBCs, several acellular haemoglobin-based oxygen carriers (HBOCs) have been developed to restore the most important function of blood: oxygen transport. One promising HBOC is the naturally extracellular haemoglobin (i.e. erythrocruorin) of Lumbricus terrestris (LtEc). The goal of this study was to maximise the portability of LtEc by lyophilising it and then testing its stability at elevated temperatures. To prevent oxidation, several cryoprotectants were screened to determine the optimum formulation for lyophilisation that could minimise oxidation of the haem iron and maximise recovery. Furthermore, samples were also deoxygenated prior to storage to decrease auto-oxidation, while resuspension in a solution containing ascorbic acid was shown to partially reduce LtEc that had oxidised during storage (e.g. from 42% Fe3+ to 11% Fe3+). Analysis of the oxygen equilibria and size of the resuspended LtEc showed that the lyophilisation, storage, and resuspension processes did not affect the oxygen transport properties or the structure of the LtEc, even after 6 months of storage at 40 °C. Altogether, these efforts have yielded a shelf-stable LtEc powder that can be stored for long periods at high temperatures, but future animal studies will be necessary to prove that the resuspended product is a safe and effective oxygen transporter in vivo.

Lyophilised protein formulations as a patient-centric dosage form: A contribution toward sustainability paradigm.

At present, society has embraced the fact apropos population aging and climate changes, that demand, amongst others, innovative pharmaceutical technologies, emphasising the development of patient-specific delivery systems and thus the provision of efficient and sustainable drugs. Protein drugs for subcutaneous administration, by allowing less frequent application, represent one of the most important parts of the pharmaceutical field, but their development is inevitably faced with obstacles in providing protein stability and suitable formulation viscosity. To gain further knowledge and fill the gaps in the already constructed data platform for the development of monoclonal antibody formulations, we designed a study that examines small model proteins, i.e., bovine serum albumin. The main aim of the presented work is to evaluate the effect of protein concentrations on critical quality attributes of both, pre-lyophilised liquid formulations, and lyophilised products. Through the study, the hypothesis that increasing protein concentration leads to higher viscosity and higher reconstitution time without affecting the stability of the protein was confirmed. The most important finding is that sucrose plays a key role in the lyophilisation of investigated protein, nevertheless, it can be predicted that, to ensure the beneficial effect of mannitol, its amount has to prevail over the amount of sucrose.

An Integrated Comprehensive Peptidomics and In Silico Analysis of Bioactive Peptide-Rich Milk Fermented by Three Autochthonous Cocci Strains.

Bioactive peptides (BPs) are molecules of paramount importance with great potential for the development of functional foods, nutraceuticals or therapeutics for the prevention or treatment of various diseases. A functional BP-rich dairy product was produced by lyophilisation of bovine milk fermented by the autochthonous strains Lactococcus lactis subsp. lactis ZGBP5-51, Enterococcus faecium ZGBP5-52 and Enterococcus faecalis ZGBP5-53 isolated from the same artisanal fresh cheese. The efficiency of the proteolytic system of the implemented strains in the production of BPs was confirmed by a combined high-throughput mass spectrometry (MS)-based peptidome profiling and an in silico approach. First, peptides released by microbial fermentation were identified via a non-targeted peptide analysis (NTA) comprising reversed-phase nano-liquid chromatography (RP nano-LC) coupled with matrix-assisted laser desorption/ionisation-time-of-flight/time-of-flight (MALDI-TOF/TOF) MS, and then quantified by targeted peptide analysis (TA) involving RP ultrahigh-performance LC (RP-UHPLC) coupled with triple-quadrupole MS (QQQ-MS). A combined database and literature search revealed that 10 of the 25 peptides identified in this work have bioactive properties described in the literature. Finally, by combining the output of MS-based peptidome profiling with in silico bioactivity prediction tools, three peptides (75QFLPYPYYAKPA86, 40VAPFPEVFGK49, 117ARHPHPHLSF126), whose bioactive properties have not been previously reported in the literature, were identified as potential BP candidates.

Effects of polyol and surfactant plasticisers on lyophilised rice starch wafers for buccal drug delivery.

Rice starch is a promising biopolymer for buccal formulations but typical oven drying may promote starch retrogradation that affects mechanical properties. Hence, lyophilisation was proposed here to improve starch product's stability. This study aims to investigate the effects of plasticisers (sorbitol and Tween® 80, T80) on the characteristics and drug release profiles of lyophilised rice starch wafers incorporated with propranolol hydrochloride. The wafers were prepared by lyophilising starch mixture (5%w/v) with plasticiser (0.2 and 0.3 g/g) and drug (10, 20, 30%w/w). Control wafers exhibited loose layers with rough wrinkled surface. Sorbitol resulted in a dense structure with higher puncture strength (PS) but lower water absorption capacity (WAC) while T80 loosened the flakes that reduced PS and increased WAC. Drug inclusion decreased PS and increased WAC of unplasticised wafers. T80-plasticised wafers with drug had a lower PS and higher WAC than sorbitol-plasticised wafers. Particularly, T80-plasticised wafers achieved outstandingly high PS and the lowest WAC at 30%w/w drug. Drug dissolution of wafers relied mainly on the drug crystallinity and WAC at 10 and 30%w/w drug. Plasticisers reduced and increased drug dissolution at 10 and 20%w/w drug, respectively. This study highlights the potential of lyophilisation in preparing rice starch wafers for buccal delivery.

Flours from fermented lentil and quinoa grains as ingredients with new techno-functional properties.

The need to provide novel, nutritious plant-based products requires seeking high-value, sustainable protein sources, like quinoa and lentils, having an increased digestibility and lacking antinutrients. Fungal fermentation has evidenced enhanced nutritional value of flours obtained from these grains. However, research into techno-functional properties, essential to the new product development, is lacking. This study investigated the techno-functional properties of flours made from lentil and quinoa after fermenting them with Pleurotus ostreatus and subjecting them to two drying techniques (lyophilisation and hot air drying). In both cases, the fermentation led to noteworthy improvements in swelling and water holding capacity, especially in those lyophilised than those dried. In contrast, the emulsifying, foaming, thickening, and gelling capacities decreased significantly. The loss of abilities was more severe for dried grains than for lyophilized ones. The thermomechanical analysis of the fermented flours showed lower thickening and gelling potential compared to untreated flours. Microscopy images revealed that the state and structure of starch granules were affected by both fermentation and drying processes. Starch granules in lentils were partly pre-gelatinised and trapped in the cotyledon cell, resulting in limited thickening and gelling abilities. In contrast, in quinoa, starch underwent pre-gelatinisation and retrogradation during the fermentation process, promoting the production of resistant starch and increasing fibre content. This study presents the potential of treated flours as ingredients possessing unique attributes compared to protein and fibre-rich conventional products.

Impact of post-freeze annealing on shrinkage of sucrose and trehalose lyophilisates.

Freeze-drying of pharmaceuticals produces lyophilisates with properties that depend on both the formulation and the process. Characterisation of the lyophilisate in terms of appearance is necessary not only to produce a visually appealing product, but also to gain insight into the freeze-drying process. The present study investigates the impact of post-freeze annealing on the volume of lyophilisates. For this purpose, sucrose and trehalose solutions were freeze-dried with different annealing conditions and the resulting lyophilisates were analysed with a 3D structured light scanner. The external structure of the lyophilisates was found to be dependent on the bulk materials as well as the choice of vials, while the volume was influenced by the annealing time and temperature. Additionally, differential scanning calorimetry was used to determine glass transition temperatures of frozen samples. As a novelty, the volumes of the lyophilisates and their corresponding glass transition temperatures were compared. This resulted in a correlation supporting the theory that the shrinkage of lyophilisates depends on the amount of residual water in the freeze-concentrated amorphous phase before drying. Understanding the volume change of lyophilisates, in combination with material properties such as glass transition temperature, forms the basis for relating physicochemical properties to process parameters in lyophilisation.

The Effect of the Plant Stabilisation Method on the Composition and Antioxidant Properties of Elderflower (Sambucus nigra L.) Extract.

Elderflower extracts are known to be a source of valuable substances that show a wide spectrum of biological activity, including antibacterial and antiviral properties, which demonstrate a degree of effectiveness against SARS CoV-2. In this work, the influence of fresh inflorescence stabilisation methods (freezing, air drying, and lyophilisation) and extraction parameters on the composition and antioxidant properties of the extracts were studied. Wild elderflower plants growing in the Malopolska Region of Poland were studied. Antioxidant activities were evaluated by 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging ability and ferric-reducing antioxidant power assays. The total phenolic content was determined using the Folin-Ciocalteu method and the phytochemical profile of the extracts was analysed using HPLC. The obtained results showed that the best method for the stabilisation of elderflower was lyophilisation, and the determined optimal maceration parameters were 60% methanol as a solvent and a process time of 1-2 days.

Application and comparison of lyophilisation protocols to enhance stable long-term storage of filovirus pseudotypes for use in antibody neutralisation tests.

AIMS: Filoviruses encompass highly pathogenic viruses placing significant public health burden on countries affected. Efforts for improved diagnostics and surveillance are needed. The requirement for high-containment can be circumvented by using pseudotype viruses (PV), which can be handled safely, in tropism, drug screening, vaccine evaluation, and serosurveillance studies. We assessed the stability and functionality after long-term storage of lyophilised filovirus pseudotypes for use in neutralisation assays. METHODS AND RESULTS: We generated a panel of filovirus lentiviral pseudotypes followed by lyophilisation and storage in different conditions. Next, we reconstituted and tested PVs in infection experiments and pseudotype neutralisation assays where possible. Lyophilised Ebola and Marburg PVs retained production titres for at least two years when stored at +4˚C or less. Lyophilised Ebola PVs performed similarly to non-lyophilised PVs in neutralisation assays after reconstitution. When stored at high temperatures (+37˚C), lyophilised PVs did not retain titres after 1-month storage, however, when lyophilised using pilot-scale facilities EBOV PVs retained titres and performed as standard in neutralisation assays after on 1-month storage at 37˚C. CONCLUSIONS: Filovirus PVs are amenable to lyophilisation and can be stored for at least 2 years in a household fridge to be used in antibody assays. Lyophilisation performed in the right conditions would allow transportation at room temperature, even in warmer climates.

Impact of formulation design and lyophilisation on the physicochemical characteristics of finasteride nanosystems.

The fundamental purpose of this study was to develop a stable lyophilised finasteride nanosystem (FNS-NS) for topical delivery. The FNS-NS was fabricated using an ultrasonication technique. The impact of two different cryoprotectants on the physicochemical characteristics of FNS-NS before and after lyophilisation was thoroughly investigated. The lyophilised FNS-NS had spherical shape with particle size lied between 188.6 nm ± 4.4 and 298.7 nm ± 4.7, low PDI values (0.26 ± 0.02 to 0.32 ± 0.02) and zeta potential ranging from -38.3 to +53.3 mV. The confocal laser microscopy depicted a comparatively higher cellular internalisation achieved for undecorated FNS-NS with respect to its chitosan-decorated counterpart. The lyophilised FNS-NS was stable for 90 days at proper storage conditions. The FNS-NS with 15% trehalose had appropriate physicochemical attributes that could be a promising carrier for topical delivery to treat androgenic alopecia.

A Novel MATLAB®-Algorithm-Based Video Analysis to Quantitatively Determine Solution Creeping in Intact Pharmaceutical Glass Vials.

During the filling process of a biopharmaceutical drug product (DP), a liquid DP film might creep up the inner vial wall which is barely discernible, appears as milky-white haze after lyophilisation and is known as fogging. Creeping and fogging are mainly dependent on the primary packaging material surface and its hydration, vial preparation process as well as DP composition. The occurrence of both can impede visual inspection and might lead to DP rejection. Hence, our studies focused on the early detection of liquid solution and glass vial surface interaction directly after filling. For a fast and highly sensitive evaluation a novel video-based analysis was used. To our knowledge, this is the first time a MATLAB®-algorithm-based video analysis was applied to quantitatively determine creeping time-resolved. Furthermore, creeping in dependence of vial processing sites, surfactant type and concentration, filling temperature, and vial format were investigated. The results were verified using orthogonal conventional methods such as surface tension, wetting behaviour, and contact angle measurements, as well as ToF-SIMS, ICP-MS, and SEM. Additionally, the methods applied were assessed regarding their cross-validation capability. The observations indicate that the vial preparation process can have a pronounced impact on alteration of the glass vial surface and related creeping behaviour of the filled solution.

Design and manufacture of a lyophilised faecal microbiota capsule formulation to GMP standards.

Faecal microbiota transplant (FMT) is an established and effective treatment for recurrent Clostridioides difficile infection (CDI) and has many other potential clinical applications. However, preparation and quality of FMT is poorly standardised and clinical studies are hampered by a lack of well-defined FMT formulations that meet regulatory standards for medicines. As an alternative to FMT suspensions for administration by nasojejunal tube or colonoscopy, which is invasive and disliked by many patients, this study aimed to develop a well-controlled, standardised method for manufacture of lyophilised FMT capsules and to provide stability data allowing storage for extended time periods. Faecal donations were collected from healthy, pre-screened individuals, homogenised, filtered and centrifuged to remove dietary matter. The suspension was centrifuged to pellet bacteria, which were resuspended with trehalose and lyophilised to produce a powder which was filled into 5 enteric-coated capsules (size 0). Live-dead bacterial cell quantitative PCR assay showed <10 fold viable bacterial load reduction through the manufacturing process. No significant loss of viable bacterial load was observed after storage at -80 °C for 36 weeks (p = 0.24, n = 5). Initial clinical experience demonstrated that the capsules produced clinical cure in patients with CDI with no adverse events reported (n = 7). We provide the first report of a detailed manufacturing protocol and specification for an encapsulated lyophilised formulation of FMT. As clinical trials into intestinal microbiota interventions proceed, it is important to use a well-controlled investigational medicinal product in the studies so that any beneficial results can be replicated in clinical practice.

Quantitative Analysis of Glassy State Relaxation and Ostwald Ripening during Annealing Using Freeze-Drying Microscopy.

Supercooling during the freezing of pharmaceutical solutions often leads to suboptimal freeze-drying results, such as long primary drying times or a collapse in the cake structure. Thermal treatment of the frozen solution, known as annealing, can improve those issues by influencing properties such as the pore size and collapse temperature of the lyophilisate. In this study we aimed to show that annealing causes a rearrangement of water molecules between ice crystals, as well as between the freeze-concentrated amorphous matrix and the crystalline ice phase in a frozen binary aqueous solution. Ice crystal sizes, as well as volume fractions of the crystalline and amorphous phases of 10% (w/w) sucrose and trehalose solutions, were quantified after annealing using freeze-drying microscopy and image labelling. Depending on the annealing time and temperature, the amorphous phase was shown to decrease its volume due to the crystallisation of vitreous water (i.e., glassy state relaxation) while the crystalline phase was undergoing coarsening (i.e., Ostwald ripening). These results allow, for the first time, a quantitative comparison of the two phenomena. It was demonstrated that glassy state relaxation and Ostwald ripening, although occurring simultaneously, are distinct processes that follow different kinetics.

Infrared Thermography for Monitoring of Freeze Drying Processes-Part 2: Monitoring of Temperature on the Surface and Vertically in Cuvettes during Freeze Drying of a Pharmaceutical Formulation.

The coupling of an infrared (IR) camera to a freeze dryer for monitoring of the temperature of a pharmaceutical formulation (sucrose/mannitol solution, 4:1%, m/m) during freeze-drying has been exploited further. The new development allows monitoring of temperatures simultaneously at the surface as well as vertically, (e.g., in depth) along the side using custom-made cuvettes. The IR camera was placed on the chamber roof of a process-scale freeze dryer. Monitoring of cuvettes containing the formulation took place from above where one side of each cuvette was equipped with a germanium window. The Ge-window was placed next to an IR mirror having a 45° angle. The long-wave infrared radiation (LWIR) coming from the inside of the cuvette was reflected upwards toward the IR camera. Accurate recording of the temperature along the cuvettes' depth profile was therefore possible. Direct imaging from -40 °C to 30 °C took place every 60 s on the surface and on the side with a 2 × 2 mm resolution per IR pixel for 45 h resulting in 2700 thermograms. Results are presented for freeze-drying of a pharmaceutical formulation as a function of time and spatially for the entire side (depth) of the cuvette. As the sublimation process was progressing, the spatial resolution (84 IR pixels for the side-view and 64 pixels for the surface-view) was more than sufficient to reveal lower temperatures deeper down in the material. The results show that the pharmaceutical formulation (a true solution at the onset) dries irregularly and that the sublimation front does not progress evenly through the material. During secondary drying, potential evaporative cooling of upper layers could be detected thanks to the high thermal and spatial resolution.

Synthesis of Ni/Y2O3 Nanocomposite through USP and Lyophilisation for Possible Use as Coating.

The Ni/Y2O3 catalyst showed high catalytic activity. Based on this, the aim of this study was to create Ni/Y2O3 nanocomposites powder with two innovative technologies, Ultrasonic Spray Pyrolysis (USP) and lyophilisation. In the USP process, thermal decomposition of the generated aerosols in an N2/H2 reduction atmosphere caused a complete decomposition of the nickel (II) nitrate to elemental Ni, which became trapped on the formed Y2O3 nanoparticles. The Ni/Y2O3 nanocomposite particles were captured via gas washing in an aqueous solution of polyvinylpyrrolidone (PVP) in collection bottles. PVP was chosen for its ability to stabilise nano-suspensions and as an effective cryoprotectant. Consequently, there was no loss or agglomeration of Ni/Y2O3 nanocomposite material during the lyophilisation process. The Ni/Y2O3 nanocomposite powder was analysed using ICP-MS, SEM-EDX, and XPS, which showed the impact of different precursor concentrations on the final Ni/Y2O3 nanocomposite particle composition. In a final step, highly concentrated Ni/Y2O3 nanocomposite ink (Ni/Y2O3 > 0.140 g/mL) and test coatings from this ink were prepared by applying them on a white matte photo paper sheet. The reflection curve of the prepared Ni/Y2O3 nanocomposite coating showed a local maximum at 440 nm with a value of 39% reflection. Given that Ni is located on the surface of the Ni/Y2O3 nanocomposite in the elemental state and according to the identified properties, tests of the catalytic properties of this coating will be performed in the future.

Ultrasound assisted extraction of bioactive compounds from pomegranate peel, their nanoencapsulation and application for improvement in shelf life extension of edible oils.

In this study pomegranate peel extract was evaluated as source of antioxidant encapsulated by nano-emulsions in soybean oil. Encapsulating agents maltodextrin (MD), whey proteins isolate (WPI) and complex of maltodextrin and whey protein isolate (MD/WPI) (1:1) were used as wall material. Average droplet size of primary W/O and double W/O/W nanoemulsions stabilised by MD, WPI and MD/WPI were 108 nm, 157.82,189.94 nm and 191.12 nm respectively. Lyophilised nanoemulsion powders were added at 100, 200 and 300 ppm concentration to soyabean and mustard oil and observed for change in various oxidative stability indices during storage and were compared to non-encapsulated extract and synthetic antioxidant BHT. From the results, it can be suggested that nanoencapsulated extract at 300 ppm concentration performed better in controlling oxidative changes in both oils than unencapsulated and synthetic one, however, extract encapsulated by MD/WPI exhibited higher antioxidant effects due to controlled release of bioactive compounds.

A field-friendly alternative to freeze-drying faeces for glucocorticoid metabolite analyses of African wild dogs (Lycaon pictus).

Endocrine studies using faeces as hormone matrix have become increasingly popular to examine adrenocortical activity in wildlife. A prerequisite for this approach is to minimize alteration of faecal glucocorticoid metabolite (fGCM) composition post-defecation. This is done by freezing the collected material as soon as possible after collection, and removing moisture from the frozen faecal samples afterwards (usually by freeze-drying). In remote areas, freeze-drying opportunities are often limited, and in the case of the African wild dog (Lycaon pictus), established assays revealed that fGCM concentrations remain comparable for only ∼24h post-defaecation. In the present study, three cost-effective drying treatments (exposure to sunlight, placement in a solar oven, and use of a food dehydrator) were investigated as alternatives to the golden standard of freeze-drying faeces.•In comparison to freeze-dried material, African wild dog faecal samples dried through sunlight exposure, a solar oven, and use of a food dehydrator revealed no significant differences in respective fGCM concentrations measured.•A food dehydrator would be the preferable option to dry African wild dog faeces if limited electrical supply is available. This technique dries faeces the fastest, and negates any reliance on weather conditions.

Addressing the unfulfilled codex standard for honey for stingless bee honey through lyophilization.

Some studies have found that the nutritional values of stingless bee honey (SBH) may be similar if not more than normal honey, prompting the Malaysian government to promote it as a superfood. However, SBH does not fulfil the Codex Standard for Honey (CODEX STAN 12-19811) in terms of moisture content and the lack of protein to be analysed with Internal Standard Carbon Isotope Ratio Analysis (ISCIRA). Hence, a lyophilization process was introduced prior to stable carbon isotope analysis of SBH to address both of these issues. It was found that once moisture content was decreased to a level below 20 % for 19 SBH samples, the percentage increment of protein extracted from the samples varied between 6 and 385 % relative to protein extracted from SBH before lyophilization with nine samples found to be adulterated. Caution is necessary when lyophilizing the SBH as significant isotope shifts were seen for SCIRA and ISCIRA values. Nevertheless, the carbon isotope shifts did not change the final outcome of the 'pass' or 'fail' of the adulteration result. Overall, the removal of water from SBH is required but caution is necessary as carbon isotope shifts were observed as SBHs underwent the lyophilization process.

One-step purification of tag free and soluble lamin B1 from an E. coli bacterial expression system.

Lamin B1 is an intermediate filament protein that is a core component of the nuclear lamina. Structural studies and biochemical characterization of lamin B1 are severely hampered by the tendency of the protein to form inclusion bodies in E. coli bacterial expression systems. Therefore, the purity and consistency of the protein varies from batch to batch. In this work, we have purified a tag-free lamin B1 protein from a soluble fraction following bacterial expression. We also checked the functional properties of the purified as well as of the subsequently lyophilised protein. The current protocol helps to purify functional lamin B1 in a single step.

Development of Bromfenac Sodium Loaded Pluronic Nanomicelles: Characterization and Corneal Permeation Study.

BACKGROUND: The Cataract is the leading cause of visual impairment and preventable blindness worldwide. Cataract removal surgery involves various post-operative complications like pain and inflammation. OBJECTIVES: The objective of this study is to screen the polymer concentration as well as optimize the formulation components to develop the pluronic micelles with nanosized characterization and for enhanced corneal permeation study. METHODOLOGY: For optimization, Central Composite design was employed to study the effect of independent variables, concentration of Pluronic F 127 (X1) and the concentration of Hyaluronic acid (X2) on chosen responses (Y 1 ) Micelle size, (Y 2 ) Entrapment Efficiency, (Y 3 ) Viscosity. The lyophilised powder was used for physical characterisation. RESULTS: The formulation containing 5%w/v Pluronic F127 and 0.2%w/v Hyaluronic acid was the optimised composition with micelle size and zeta potential 38.74±4.12nm and -17.6±0.1 mV respectively. In-vitro drug release was found to be 91.72±1.2 percentage in 8 hours. Surface morphology revealed micelles were spherical in shape. Ocular irritancy study showed that formulation was safe and non-irritant. In vitro corneal permeation studies through excised rabbit cornea indicated 1.5 fold increase in ocular availability without corneal damage compared to an aqueous suspension containing the same amount of drug in nanomicelles. CONCLUSION: In a nutshell, Pluronic Nanomicelles would be a platform for the delivery of Bromfenac Sodium.

Production, Titration, Neutralisation, Storage and Lyophilisation of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Lentiviral Pseudotypes.

This protocol details a rapid and reliable method for the production and titration of high-titre viral pseudotype particles with the SARS-CoV-2 spike protein (and D614G or other variants of concern, VOC) on a lentiviral vector core, and use for neutralisation assays in target cells expressing angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2). It additionally provides detailed instructions on substituting in new spike variants via gene cloning, lyophilisation and storage/shipping considerations for wide deployment potential. Results obtained with this protocol show that SARS-CoV-2 pseudotypes can be produced at equivalent titres to SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV) pseudotypes, neutralised by human convalescent plasma and monoclonal antibodies, and stored at a range of laboratory temperatures and lyophilised for distribution and subsequent application.