Characterization of forced degradation products of ketorolac tromethamine using LC/ESI/Q/TOF/MS/MS and in silico toxicity prediction

Potential degradation products of abemaciclib: Identification and structural characterization employing LC-Q/TOF-MS and NMR including mechanistic explanation

Degradation products are the potential drug impurities that can be generated during transport and storage of pharmaceuticals. Before this study, degradation chemistry and potential degradation products of abemaciclib (ABM) were unknown. Moreover, no stability-indicating analytical method was available that can be used to analyse ABM in presence of its degradation products. In this study, stress testing on ABM was carried out under oxidative, thermal, photolytic (UV & visible), and hydrolytic (acid, alkaline, and neutral) degradation conditions. The study revealed that ABM is susceptible to photolytic, oxidative, and thermal stress leading to the formation of five degradation products (DPs). ABM and its degradation products were chromatographically separated employing a developed RP-HPLC-based stability-indicating analytical method. The method was transferred to an LC-Q-TOF system for further analysis. To elucidate the structure of degradation products, fragmentation pathway of ABM was initially established through high-resolution mass spectrometry (HRMS). Subsequently, mass fragmentation pathways of all the DPs have been established through HRMS and MSn based analysis. The major degradation product was isolated and fully characterized using atmospheric chemical ionization-mass spectrometry and nuclear magnetic resonance techniques. ABM showed extensive degradation under oxidative and photolytic systems. Therefore, special care may be sought during storage and transport of ABM or its formulations to avoid photolytic and oxidative stress exposure to the drug. Lastly, in silico toxicity of the characterized degradation products was assessed employing ProTox ІІ online web predictor freeware in which some of them were found to have the potential of hepatotoxicity, immunogenicity and mutagenicity.

Preformulation-Assisted Design of Ketorolac Tromethamine for Effective Ophthalmic Delivery

Background: The eye is a highly protected organ from ocularly administered drugs; drug- and formulation-related factors contribute significantly to ocular bioavailability. There has been a growing interest in using nonsteroidal anti-inflammatory drugs in ophthalmology for treating postoperative pain, inflammation, and seasonal allergic conjunctivitis. A preformulation-assisted design boosts efficacy and reduces dose requirements. Methods: This work aims to study the preformulation characteristics of ketorolac tromethamine to improve ocular performance and future formulation development through developing an high-performance liquid chromatography (HPLC) stability-indicating assay, forced degradation under stress conditions, solubility, as well as partition and distribution coefficient measurements. An isocratic HPLC with diode array detector method was developed and validated. Accelerated degradation under different stressors (acid, alkali, heat, and oxidative) was studied. In addition, solubility, partition, and distribution were investigated at different pHs of 3.5-7.4. Results: The results indicated that the developed HPLC method was simple, rapid (retention time ≃3 min), sensitive, selective, robust, and stability indicating. The drug seems more chemically sensitive to acid degradation (∼30% and 40% of the drug was degraded under 0.1 M and 1 M HCl at 60°C for 24 h, respectively). Another significant degradation was recorded in the following order: Oxidative > alkali > heat (phosphate-buffered saline) > heat (distilled water). Being a weak ionizable drug, both water and lipid solubility, as measured through partition coefficients, it demonstrated pH-dependency. Conclusion: For the optimum balance of water and lipid solubility required for penetration through the lipophilic corneal epithelial barrier, ketorolac eye drops would be better formulated between pH 5.5 and 6.6 than being formulated at the physiological fluid pH 7.4, where the drug is extremely hydrophilic and less permeable.

Hydrogel device for analgesic drugs with in-situ loading and polymerization

The high prevalence of opioid addiction and the shortcomings of systemic opioids has increased the pace of the search for alternative methods of pain management. The local delivery of pain medications has started to be used as a tool for pain management and to decrease the use of systemic opioids for these patients. Here, we explored an in-situ polymerizable hydrogel system for the local delivery of analgesics and nonsteroid anti-inflammatory drugs (NSAID) for orthopaedic applications. We synthesized a series of methacrylated oligomeric polyethylene glycol-co-lactic acid polymer using microwave radiation for the delivery of bupivacaine hydrochloride as an analgesic and ketorolac tromethamine as an NSAID. We determined drug elution and gel degradation profiles in vitro. Biocompatibility was assessed against osteoblasts in vitro and by histological analysis after subcutaneous implantation for 4 weeks in vivo. Intra-articular and systemic concentrations and pharmacokinetic parameters were estimated using a two-compartment pharmacodynamic model based on in-vitro elution profiles. This type of in-situ applicable hydrogels is promising for extending the local efficacy of pain medication and further reducing the need for opioids.

A study on structural characterization of potential impurities of Sugammadex sodium using LC/ESI/QTOF/MS/MS and NMR

The first selective relaxant binding agent (SRBA), Sugammadex sodium (SGS) is used to reverse anesthesia. A study of the process related and degradation products will help to optimize process parameters and also to develop the analytical methods and set the quality standard for a quality control strategy in pharmaceutical industry. During the manufacture of SGS, all the process related impurities are controlled in every stage and process related and degradation products are controlled in the active pharmaceutical ingredient (API) as per ICH guidelines. A total of nine process related and degradation impurities of SGS (Impurity-A to Impurity-I) were isolated and characterized by using LC/ESI/QTOF/MS/MS and NMR studies.

Optimization of structures, biochemical properties of ketorolac and its degradation products based on computational studies

BACKGROUND

Ketorolac (KTR) is used as an analgesic drug with an efficacy close to that of the opioid family. It is mainly used for the short term treatment of post-operative pain. It can inhibit the prostaglandin synthesis by blocking cyclooxygenase (COX).

METHODS

In this investigation, the inherent stability and biochemical interaction of Ketorolac (KTR) and its degradation products have been studiedon the basis of quantum mechanical approaches. Density functional theory (DFT) with B3LYP/ 6-31G (d) has been employed to optimize the structures. Thermodynamic properties, frontier molecular orbital features, dipole moment, electrostatic potential, equilibrium geometry, vibrational frequencies and atomic partial charges of these optimized structureswere investigated. Molecular docking has been performed against prostaglandin H2 (PGH2) synthase protein 5F19 to search the binding affinity and mode(s). ADMET prediction has performed to evaluate the absorption, metabolism and carcinogenic properties.

RESULTS

The equilibrium geometry calculations support the optimized structures. Thermodynamic results disclosed the thermal stability of all structures. From molecular orbital data, all the degradents are chemically more reactive than parent drug (except K3). However, the substitution of carboxymethyl radicalin K4 improved the physicochemical properties and binding affinity. ADMET calculations predict the improved pharmacokinetic and non-carcinogenic properties of all degradents.

CONCLUSION

Based on physicochemical, molecular docking, and ADMET calculation, this study can be helpful to understand the biochemical activities of Ketorolac and its degradents and to design a potent analgesic drug.

A study on structural characterization of degradation products of cangrelor using LC/QTOF/MS/MS and NMR

A complete degradation study was performed on cangrelor drug substance as per the ICH guidelines. The study reveals that a total of six degradation products (DP-1 to DP-6) were found and out of these, three unknown degradation products (DP-1, DP-5 and DP-6) were not reported in the literature. Based on the degradation study, the drug substance cangrelor was found to be sensitive towards acidic, basic and oxidative conditions. Besides, it was stable under thermal and photolytic stress conditions. The degradation products were characterized by using advanced LC/QTOF and MS/MS analysis. Further, the structures were characterized by NMR studies. The identified degradation products of cangrelor are valuable for cangrelor manufacturing process and quality control.

Synthesis, structure, antioxidant activity, and water solubility of trolox ion conjugates

The interaction of trolox with ammonia, alkylamines of different classes, and amino derivatives of heterocyclic compounds, including nitroxyl radicals and alkaloids, led to the production of ammonium salts called ion conjugates (ICs). Five ICs were characterised by X-ray diffraction. This is the first time a wide range of ICs were made from trolox with amines, and ESI-MS data demonstrated they have the potential to generate pseudomolecular [(A⁻B⁺) + H]⁺ ions. For all obtained trolox ICs, a significant increase (1–3 orders of magnitude) in water solubility was achieved while retaining high antioxidant activity. ICs synthesised from two biologically active fragments may be used to create polyfunctional agents with varying solubility and bioavailability.