Synthesis, characterization, cytotoxicity evaluation, and molecular docking with DNA, bovine serum albumin, and SARS-Cov-2 of copper complexes bearing tris-(2-pyridyl)-pyrazolyl borate ligand

Four copper (II) complexes bearing tris-(2-pyridyl)-pyrazolyl borate (Tppy) ligand with corresponding chloride (Cu-1), aqua (Cu-2), azide (Cu-3), and thiocyanide (Cu-4) substitutions were synthesized and characterized by spectroscopic and analytical methods. Spectroscopic and molecular docking studies were employed to investigate the interactions of these complexes with calf thymus (CT) DNA and bovine serum albumin (BSA). The results inferred intercalation binding mode of the complexes with DNA. All the complexes exhibited good binding with BSA as well. In addition, the binding efficacy of the Cu (II) complexes with SARS-Cov-2 was tested in silico. Further, in vitro anticancer activity of the complexes was investigated against the HeLa-cervical, HepG2-liver and A549-lung cancer, and one normal (L929-fibroblast) cell line. IC50 values unveiled that the complexes were more active than cisplatin against all three cancer cells. It was understood that complex Cu-3 containing azide substitution displayed the highest activity on the HeLa cell line (IC50 = 6.3 μM). More importantly, TppyCu (II) complexes were not active against the normal cell line. Lastly, the acridine orange/ethidium bromide (AO/EB) and 4′,6-diamidino-2-phenylindole staining assays indicated that Cu-3 induced cell death in HeLa cells at the late apoptotic stage. This complex also efficiently generated ROS in HeLa cells promoting apoptosis as understood from the DCFH-DA assay. © 2023 John Wiley & Sons, Ltd.

Development and Validation of an Innovative Analytical Approach for the Quantitation of Tris(Hydroxymethyl)Aminomethane (TRIS) in Pharmaceutical Formulations by Liquid Chromatography Tandem Mass Spectrometry.

A novel COVID-19 vaccine (BriLife®) has been developed by the Israel Institute for Biological Research (IIBR) to prevent the spread of the SARS-CoV-2 virus throughout the population in Israel. One of the components in the vaccine formulation is tris(hydroxymethyl)aminomethane (tromethamine, TRIS), a buffering agent. TRIS is a commonly used excipient in various approved parenteral medicinal products, including the mRNA COVID-19 vaccines produced by Pfizer/BioNtech and Moderna. TRIS is a hydrophilic basic compound that does not contain any chromophores/fluorophores and hence cannot be retained and detected by reverse-phase liquid chromatography (RPLC)-ultraviolet (UV)/fluorescence methods. Among the few extant methods for TRIS determination, all exhibit a lack of selectivity and/or sensitivity and require laborious sample treatment. In this study, LC−mass spectrometry (MS) with its inherent selectivity and sensitivity in the multiple reaction monitoring (MRM) mode was utilized, for the first time, as an alternative method for TRIS quantitation. Extensive validation of the developed method demonstrated suitable specificity, linearity, precision, accuracy and robustness over the investigated concentration range (1.2−4.8 mg/mL). Specifically, the R2 of the standard curve was >0.999, the recovery was >92%, and the coefficient of variance (%CV) was <12% and <6% for repeatability and intermediate precision, respectively. Moreover, the method was validated in accordance with strict Good Manufacturing Practice (GMP) guidelines. The developed method provides valuable tools that pharmaceutical companies can use for TRIS quantitation in vaccines and other pharmaceutical products.

Potential of a methanolic extract of Lawsonia inermis (L.) leaf as an alternative sanitiser in the time of COVID-19 Pandemic and beyond.

To harness the antimicrobial properties of a crude methanolic extract of Henna (Lawsonia inermis) leaf as a potential alternative sanitiser, there is the need to test its performance in different solutions. In this work, the effects of distilled water (dH20), Acetate-HCL (AH) Buffer (pH 4.6), Phosphate Buffer Saline (PBS) (pH 7.2) and Tris-HCL (TBH) Buffer (pH 8.6) on the antibacterial and antiviral activity of the extract were assessed. Through standard phytochemical screening and HPLC-MS (LCMS STANDARD 7.M), it was found that the extract consisted of about 30 different compounds including flavonoids. The extent of the antimicrobial activity of the extract in solutions was in the increasing order of AH > dH2O >>>> TBH > PBS. Under the same conditions, reduced antibacterial activity and complete cessation of the antiviral activity of the extract in TBH and PBS was observed. However, in AH and dH20, within 1-5 min, 1 mg ml-1, 0.125 mg ml-1 and 0.0625 mg ml-1 of the extract caused complete inactivation of E.coli (reductions of 8.2 log CFU ml-1), B. subtilis (reductions of 8.2 log CFU ml-1) and MS2 (reductions of 9.7 log PFU ml-1) respectively. The fluorescence microscopy images of the live/dead staining of the inactivated bacterial samples validated the extent of the inactivation. The broad spectrum and high antimicrobial activity of the extract, coupled with the plant not a staple food, has long history of safe use by humans as a medicine and cosmetic, cheaply available in abundance in many regions of the world, thus making the extract a potential candidate as an alternative sanitiser in the time of COVID-19 Pandemic and beyond.

Regenerable and high-throughput surface plasmon resonance assay for rapid screening of anti-SARS-CoV-2 antibody in serum samples.

Current serological antibody tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) require enzyme or fluorescent labels, and the titer well plates cannot be reused. By immobilizing histidine (His)-tagged SARS-CoV-2 spike (S1) protein onto tris‒nitrilotriacetic acid (tris-NTA) sensor and using the early association phase for mass-transfer-controlled concentration determination, we developed a rapid and regenerable surface plasmon resonance (SPR) method for quantifying anti-SARS-CoV-2 antibody. On a five-channel SPR instrument and with optimized S1 protein immobilization density, each of the four analytical channels is sequentially used for multiple measurements, and all four channels can be simultaneously regenerated once they have reached a threshold value. Coupled with a programmable autosampler, each sensor can be regenerated at least 20 times, enabling uninterrupted assays of more than 800 serum samples. The accuracy and speed of our method compare well with those of the enzyme-linked immunosorbent assay (ELISA), and the detection limit (0.057 µg mL-1) can easily meet the requirement for screening low antibody levels such as those in convalescent patients. In addition, our method exhibits excellent channel-to-channel (RSD = 1.9%) and sensor-to-sensor (RSD = 2.1%) reproducibility. Obviation of an enzyme label drastically reduced the assay cost, rending our method (<60 cents) much more cost effective than those of commercial ELISA kits ($4.4-11.4). Therefore, our method offers a cost-effective and high-throughput alternative to the existing methods for serological measurements of anti-SARS-CoV-2 antibody levels, holding great promise for rapid screening of clinical samples without elaborate sample pretreatments and special reagents.

Sensitive and rapid on-site detection of SARS-CoV-2 using a gold nanoparticle-based high-throughput platform coupled with CRISPR/Cas12-assisted RT-LAMP.

The outbreak of corona virus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to a global pandemic. The high infectivity of SARS-CoV-2 highlights the need for sensitive, rapid and on-site diagnostic assays of SARS-CoV-2 with high-throughput testing capability for large-scale population screening. The current detection methods in clinical application need to operate in centralized labs. Though some on-site detection methods have been developed, few tests could be performed for high-throughput analysis. We here developed a gold nanoparticle-based visual assay that combines with CRISPR/Cas12a-assisted RT-LAMP, which is called Cas12a-assisted RT-LAMP/AuNP (CLAP) assay for rapid and sensitive detection of SARS-CoV-2. In optimal condition, we could detect down to 4 copies/µL of SARS-CoV-2 RNA in 40 min. by naked eye. The sequence-specific recognition character of CRISPR/Cas12a enables CLAP a superior specificity. More importantly, the CLAP is easy for operation that can be extended to high-throughput test by using a common microplate reader. The CLAP assay holds a great potential to be applied in airports, railway stations, or low-resource settings for screening of suspected people. To the best of our knowledge, this is the first AuNP-based colorimetric assay coupled with Cas12 and RT-LAMP for on-site diagnosis of COVID-19. We expect CLAP assay will improve the current COVID-19 screening efforts, and make contribution for control and mitigation of the pandemic.