Systematic stability testing of insulins as representative biopharmaceuticals using ATR FTIR-spectroscopy with focus on quality assurance

Degradation of Emerging Pharmaceutical Pollutants from Wastewater Using Penicillium aurantiogriseum 2AJS

Approximately 3000 pharmaceutical compounds and personal care products (PPCPs) are utilized and discharged into the wastewater at low levels, and they are rarely removed or treated in wastewater treatment facilities. The present study focused on the potential ability of Penicillium aurantiogriseum 2AJS to degrade pharmaceutical and personal care products of different classes of drugs: antipyretic and analgesic drugs (paracetamol, diclofenac, and ibuprofen) and hormones (estrogen, progesterone, and testosterone). Various ligninolytic extracellular enzymatic studies were also studied. A phytotoxicity assay was performed using the Lemna minor species procured from the Vellore Institute of Technology, Vellore. The results revealed degradation of pharmaceutical and personal care products to 95.27% (paracetamol), 94.37% (diclofenac), 89.29% (ibuprofen), 94.16% (progesterone), 91.10% (estrogen), and 82.12% (testosterone). GC-MS and NMR analyses aided in proposing the degradation pathway of all six pharmaceutical compounds. Degradation kinetics showed a first-order model for all the degradation studies with R2 values ranging between 0.89 and 0.95. A toxicological assay using Lemna minor showed very less toxicity of degraded compounds with a toxicity index ranging between 1.2 and 1.5 compared to the parent compounds. Hence, strain 2AJS can be used in in situ bioremediation of wastewater treatment processes.

Iontophoretically controlled insulin delivery via water-soluble conductive polymer PANI:PSS and thermoplastic polyurethane matrix

Transdermal insulin delivery is an alternative route to deliver insulin through the body skin with the challenges to overcome the low drug skin permeability and high molecular weight. Polyaniline doped with poly(4-styrenesulfonic acid) (PANI:PSS), a conductive polymer with the high electrical conductivity, was synthesized and utilized as a drug carrier to improve the drug delivery capability from a porous thermoplastic polyurethane (TPU) matrix. The insulin was electrostatically attached to PANI:PSS based on the ion exchange between insulin and PSS. For the in vitro drug release of insulin loaded PANI:PSS relative to the pristine insulin alone, the amount of insulin released was improved to 84.70% with the time to equilibrium of 2 h under the electrical field of 6 V. For the ex vivo release-skin permeation, the amount insulin released and permeated became lower at 57.02% with time to equilibrium of 2 h, due to the pig skin acting as a barrier for insulin permeation. The modified insulin transdermal delivery, with PANI:PSS as the drug carrier and drug enhancer relative to without, is shown here to influence the insulin release rate, amount, and duration, suitable to treat diabetes patients.

Thermal stability and storage of human insulin

BACKGROUND

Health authorities stress the temperature sensitivity of human insulin, advising protection from heat and freezing, with manufacturers suggesting low-temperature storage for intact vials, and once opened, storage at room temperature for four to six weeks, though usage time and maximum temperature recommendations vary. For human insulin, the recommendations of current shelf life in use may range from 10 to 45 days, and the maximum temperature in use varies between 25 °C and 37 °C. Optimal cold-chain management of human insulin from manufacturing until the point of delivery to people with diabetes should always be maintained, and people with diabetes and access to reliable refrigeration should follow manufacturers' recommendations. However, a growing segment of the diabetes-affected global population resides in challenging environments, confronting prolonged exposure to extreme heat due to the climate crisis, all while grappling with limited access to refrigeration.

OBJECTIVES

To analyse the effects of storing human insulin above or below the manufacturers' recommended insulin temperature storage range or advised usage time, or both, after dispensing human insulin to people with diabetes.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 12 July 2023.

SELECTION CRITERIA

We included clinical and laboratory studies investigating the storage of human insulin above or below manufacturers' recommended temperature storage range, advised usage time, or both.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We used GRADE to assess the certainty of evidence for the clinical study. Most information emerged from in vitro studies, mainly from pharmaceutical companies. There is no validated risk of bias and certainty of evidence rating for in vitro studies. We thus presented a narrative summary of the results.

MAIN RESULTS

We included 17 eligible studies (22 articles) and additional information from pharmaceutical companies. Pilot clinical study One pilot clinical study investigated temperature conditions for insulin stored for six weeks in an unglazed clay pot with temperatures ranging between 25 °C and 27 °C. The mean fall in plasma glucose in eight healthy volunteers after clay pot-stored insulin injection was comparable to refrigerator-stored insulin injection (very low-certainty evidence). In-vitro studies Nine, three and four laboratory studies investigated storage conditions for insulin vials, insulin cartridges/pens and prefilled plastic syringes, respectively. The included studies reported numerous methods, laboratory measurements and storage conditions. Three studies on prefilled syringes investigating insulin potency at 4 °C up to 23 °C for up to 28 days showed no clinically relevant loss of insulin activity. Nine studies examined unopened vials and cartridges. In studies with no clinically relevant loss of insulin activity for human short-acting insulin (SAI), intermediate-acting insulin (IAI) and mixed insulin (MI) temperatures ranged between 28.9 °C and 37 °C for up to four months. Two studies reported up to 18% loss of insulin activity after one week to 28 days at 37 °C. Four studies examined opened vials and cartridges at up to 37 °C for up to 12 weeks, indicating no clinically relevant reduction in insulin activity. Two studies analysed storage conditions for oscillating temperatures ranging between 25 °C and 37 °C for up to 12 weeks and observed no loss of insulin activity for SAI, IAI and MI. Four studies, two on vials (including one on opened vials), and two on prefilled syringes, investigated sterility and reported no microbial contamination. Data from pharmaceutical companies Four manufacturers (BIOTON, Eli Lilly and Company, Novo Nordisk and Sanofi) provided previously unreleased human insulin thermostability data mostly referring to unopened containers (vials, cartridges). We could not include the data from Sanofi because the company announced the permanent discontinuation of the production of human insulins Insuman Rapid, Basal and Comb 25. BIOTON provided data on SAI after one, three and six months at 25 °C: all investigated parameters were within reference values, and, compared to baseline, loss of insulin activity was 1.1%, 1.0% and 1.7%, respectively. Eli Lilly and Company provided summary data: at below 25 °C or 30 °C SAI/IAI/MI could be stored for up to 25 days or 12 days, respectively. Thereafter, patient in-use was possible for up to 28 days. Novo Nordisk provided extensive data: compared to baseline, after three and six months at 25 °C, loss of SAI activity was 1.8% and 3.2% to 3.5%, respectively. Loss of IAI activity was 1.2% to 1.9% after three months and 2.0% to 2.3% after six months. Compared to baseline, after one, two and three months at 37 °C, loss of SAI activity was 2.2% to 2.8%, 5.7% and 8.3% to 8.6%, respectively. Loss IAI activity was 1.4% to 1.8%, 3.0% to 3.8% and 4.7% to 5.3%, respectively. There was no relevant increase in insulin degradation products observed. Up to six months at 25 °C and up to two months at 37 °C high molecular weight proteins were within specifications. Appearance, visible particles or macroscopy, particulate matter, zinc, pH, metacresol and phenol complied with specifications. There were no data for cold environmental conditions and insulin pumps.

AUTHORS' CONCLUSIONS

Under difficult living conditions, pharmaceutical companies' data indicate that it is possible to store unopened SAI and IAI vials and cartridges at up to 25 °C for a maximum of six months and at up to 37 °C for a maximum of two months without a clinically relevant loss of insulin potency. Also, oscillating temperatures between 25 °C and 37 °C for up to three months result in no loss of insulin activity for SAI, IAI and MI. In addition, ambient temperature can be lowered by use of simple cooling devices such as clay pots for insulin storage. Clinical studies on opened and unopened insulin containers should be performed to measure insulin potency and stability after varying storage conditions. Furthermore, more data are needed on MI, insulin pumps, sterility and cold climate conditions.

Engineering Flexible Metal-Phenolic Networks with Guest Responsiveness via Intermolecular Interactions

Flexible metal-organic materials are of growing interest owing to their ability to undergo reversible structural transformations under external stimuli. Here, we report flexible metal-phenolic networks (MPNs) featuring stimuli-responsive behavior to diverse solute guests. The competitive coordination of metal ions to phenolic ligands of multiple coordination sites and solute guests (e.g., glucose) primarily determines the responsive behavior of the MPNs, as revealed experimentally and computationally. Glucose molecules can be embedded into the dynamic MPNs upon mixing, leading to the reconfiguration of the metal-organic networks and thus changes in their physicochemical properties for targeting applications. This study expands the library of stimuli-responsive flexible metal-organic materials and the understanding of intermolecular interactions between metal-organic materials and solute guests, which is essential for the rational design of responsive materials for various applications.

Inspecting Insulin Products Using Water Proton NMR. I. Noninvasive vs Invasive Inspection

BACKGROUND

There is a clear need to transition from batch-level to vial/syringe/pen-level quality control of biologic drugs, such as insulin. This could be achieved only by noninvasive and quantitative inspection technologies that maintain the integrity of the drug product.

METHODS

Four insulin products for patient self-injection presented as prefilled pens have been noninvasively and quantitatively inspected using the water proton NMR technology. The inspection output is the water proton relaxation rate R₂(¹H₂O), a continuous numerical variable rather than binary pass/fail.

RESULTS

Ten pens of each product were inspected. R₂(¹H₂O) displays insignificant variation among the 10 pens of each product, suggesting good insulin content uniformity in the inspected pens. It is also shown that transferring the insulin solution out of and then back into the insulin pen caused significant change in R₂(¹H₂O), presumably due to exposure to O₂ in air.

CONCLUSIONS

Water proton NMR can noninvasively and quantitatively inspect insulin pens. wNMR can confirm product content uniformity, but not absolute content. Its sensitivity to sample transferring provides a way to detect drug product tampering. This opens the possibility of inspecting every pen/vial/syringe by manufacturers and end-users.

Chemical Bonding of Biomolecules to the Surface of Nano-Hydroxyapatite to Enhance Its Bioactivity

Hydroxyapatite (HA) is a significant constituent of bones or teeth and is widely used as an artificial bone graft. It is often used to replace the lost bones or in reconstructing alveolar bones before dental implantation. HA with biological functions finds its importance in orthopedic surgery and dentistry to increase the local concentration of calcium ions, which activate the growth and differentiation of mesenchymal stem cells (MSC). To make relevant use of HA in bone transplantation, the surfaces of orthopedic and dental implants are frequently coated with nanosized hydroxyapatite (nHA), but its low dispersibility and tendency to form aggregates, the purpose of the surface modification of bone implants is defeated. To overcome these drawbacks and to improve the histocompatibility of bone implants or to use nHA in therapeutic applications of implants in the treatment of bone diseases, various studies suggested the attachment of biomolecules (growth factors) or drugs through chemical bonding at the surface of nHA. The growth factors or drugs bonded physically at the surface of nHA are mostly unstable and burst released immediately. Therefore, reported studies suggested that the surface of nHA needs to be modified through the chemical bonding of biologically active molecules at the surface of bone implants such as proteins, peptides, or naturally occurring polysaccharides to prevent the aggregation of nHA and to get homogenous dispersion of nHA in solution. The role of irradiation in producing bioactive and antibacterial nHA through morphological variations in surfaces of nHA is also summarized by considering internal structures and the formation of reactive oxygen species on irradiation. This mini-review aims to highlight the importance of small molecules such as proteins, peptides, drugs, and photocatalysts in surface property modification of nHA to achieve stable, bioactive, and antibacterial nHA to act as artificial bone implants (scaffolds) in combination with biodegradable polymers.

Subcutaneous amyloidoma models for screening potential anti-fibrillating agents in vivo

Here, we describe a robust protocol using mouse models to screen potential insulin-stabilizers and insulin moieties. We have generated a mouse model of amyloidoma, found in diabetic patients undergoing insulin therapy. This model can be used to screen potential insulin stabilizers and insulin moieties to prevent amyloidoma formation. This protocol can further be used for the preclinical validation of therapeutically relevant insulin stabilizers and formulations. The protocol highlights all the critical steps for generating amyloidoma in a preclinical model.

For complete details on the use and execution of this profile, please refer to Mukherjee et al. (2021).

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We present a detailed protocol for the generation of subcutaneous amyloidoma in mice

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This protocol facilitates screening of novel insulin-stabilizing molecules in vivo

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This approach can be adapted to study amyloidosis in other amyloid-related diseases