Synthesis and characterization of antimicrobial colloidal polyanilines

The potential application of colloidal polyaniline (PANI) as an antimicrobial is limited by challenges related to solubility in common organic solvents, scalability, and antimicrobial potency. To address these limitations, we introduced a functionalized PANI (fPANI) with carboxyl groups through the polymerisation of aniline and 3-aminobenzoic acid in a 1:1 molar ratio. fPANI is more soluble than PANI which was determined using a qualitative study. We further enhanced the solubility and antimicrobial activity of fPANI by incorporating Ag nanoparticles onto the synthesized fPANI colloid via direct addition of 10 mM AgNO3. The improved solubility can be attributed to an approximately 3-fold reduction in size of particles. Mean particle sizes are measured at 1322 nm for fPANI colloid and 473 nm for fPANI-Ag colloid, showing a high dispersion and deagglomeration effect from Ag nanoparticles. Antimicrobial tests demonstrated that fPANI-Ag colloids exhibited superior potency against Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli, and Bacteriophage PhiX 174 when compared to fPANI alone. The minimum bactericidal concentration (MBC) and minimum virucidal concentration (MVC) values were halved for fPANI-Ag compared to fPANI colloid and attributed to the combination of Ag nanoparticles with the fPANI polymer. The antimicrobial fPANI-Ag colloid presented in this study shows promising results, and further exploration into scale-up can be pursued for potential biomedical applications

Mavacamten: a novel avenue towards hypertrophic obstructive cardiomyopathy

Hypertrophic obstructive cardiomyopathy (HCM) is the most common heterogeneous genetic cardiovascular disorder. Its pathophysiology involves left ventricular hypertrophy, increased fibrosis, hypercontractility, and reduced compliance. The symptomatic obstructive HCM presents as dyspnoea, syncope, chest pain, palpitations, arrhythmias, or sudden death, usually after provocative manoeuvres like exercise. Until April 2022, treatment options were disease non-specific like Beta blockers, Cardio-selective Calcium Channel Blockers, Dipyridamole, and Ranolazine. Mavacamten is a first-in-class, FDA-approved drug molecule for HCM. It works by selective and reversible inhibition of the cardiac myosin ATPase thereby decreasing the formation of actin- myosin cross- bridges in systole and diastole. The excessive actin-myosin cross-bridging is the hallmark of disease and is responsible for the compromised functioning of the heart in both the systole and diastole phase due to left ventricular outflow tract (LVOT) obstruction and increased ventricular filling pressure respectively. Mavacamten acts by producing super-relaxed state of heart which is then translated into decreased LVOT obstruction and improved cardiac filling pressures thereby improving the functional capacity and symptoms in patients with New York Heart Association (NYHA) stage II, and III symptomatic or obstructive heart failure. Mavacamten is administered orally 2.5-15 mg per day with titration guided by lab investigations and clinical symptoms. Its bioavailability is 85%, undergoes metabolism by CYP2C19 and CYP3A4 and is excreted mainly in urine. It is also an enzyme inducer and shows considerable drug interactions. Common adverse effects are dizziness and syncope. Sometimes the drug may worsen heart failure or completely block ventricular function. Mavacamten has raised hopes for the possibility of managing this potentially lethal intrigue disorder with medicines alone

Lamotrigine, a Miscreant in Toxic Epidermal Necrolysis: A Rare Case Report

This case report is about a rural 39 years old female of Asian origin and laborer by profession who developed Toxic Epidermal Necrolysis (TEN) with lamotrigine. She was a known case of Bipolar Affective Disorder Type 1 with psychosis on treatment with quetiapine, duloxetine, escitalopram, and etizolam for the last one and a half years and had no history of adverse effects with those drugs. Recently Lamotrigine was added to her regimen at a dose of 50 mg/day. She developed Stevens-Johnson syndrome (SJ syndrome) within two weeks of adding lamotrigine which progressed to Toxic Epidermal Necrolysis (TEN), SCORTEN scores 3, in the next 3-4 days. The sequence of events, reports of laboratory investigations, and management of TEN have been elaborated in this case report. On the Naranjo scale of causality, the suspected adverse drug reaction was established as ‘probable’ because the suspected culprit drug discontinuation led to improvement in the patient’s condition but a re-challenge was not tried

A Cross-sectional Study to Assess the Incidence of Adverse Drug Reactions to the Covishield Vaccine among Healthcare Workers of a Tertiary Care Government Institute in North India

Background: Vaccines are a key strategy to stop the COVID19 pandemic. The present study was conducted to assess the incidence of Adverse Drug Reactions to the Covishield vaccine among healthcare workers. Materials and Methods: A cross-sectional, observational, questionnaire-based study was carried out on healthcare workers of R.U.H.S. College of Medical Sciences, Jaipur, Rajasthan. The study tool consisted of a digital questionnaire. Results: The present study was carried out among 316 healthcare workers who received the first dose of the Covishield vaccine. 83 (26.26%) participants complained of side effects after receiving the first dose of the Covishield vaccine. Fatigue (64), fever (52), body ache (40), swelling at the vaccination site (35), headache (25), and pain in the limb (18) were the most prevalent symptoms. Most post-vaccination symptoms were found to be mild. 67 participants showed side effects of vaccination within 24 hours while 16 showed side effects after 24 hours. Conclusion: This study reflects that one fourth of participants complained of side effects after receiving the first dose of the Covishield vaccine. These side effects are not severe and should not be an obstacle to the successful control of the Covid-19 pandemic in India

Nanosizing techniques for improving bioavailability of drugs

The poor solubility of significant number of Active Pharmaceutical Ingredients (APIs) has become a major challenge in the drug development process. Drugs with poor solubility are difficult to formulate by conventional methods and often show poor bioavailability. In the last decade, attention has been focused on developing nanocrystals for poorly water soluble drugs using nanosizing techniques. Nanosizing is a pharmaceutical process that changes the size of a drug to the sub-micron range in an attempt to increase its surface area and consequently its dissolution rate and bioavailability. The effectiveness of nanocrystal drugs is evidenced by the fact that six FDA approved nanocrystal drugs are already on the market. The bioavailabilities of these preparations have been significantly improved compared to their conventional dosage forms. There are two main approaches for preparation of drug nanocrystals; these are the top-down and bottom-up techniques. Top-down techniques have been successfully used in both lab scale and commercial scale manufacture. Bottom-up approaches have not yet been used at a commercial level, however, these techniques have been found to produce narrow sized distribution nanocrystals using simple methods. Bottom-up techniques have been also used in combination with top-down processes to produce drug nanoparticles. The main aim of this review article is to discuss the various methods for nanosizing drugs to improve their bioavailabilities

A Stability Indicating HPLC Method to Determine Actual Content and Stability of Nicotine within Electronic Cigarette Liquids

(1) Background: Despite the growing use of e-cigarettes, in most countries, there is no regulation covering manufacturing standards of the solution (‘e-liquid’), leading to concerns over the accuracy of labelling and stability of the products under a range of conditions. Following the United States (US) Food and Drug Administration (FDA) requirements for manufacture of e-liquids, we aimed to develop a simple high-performance liquid chromatography (HPLC) method to determine nicotine content in nicotine-containing e-liquids, even in the presence of degradation products; (2) Methods: We developed an HPLC method to quantify nicotine in the presence of the two major constituents of all e-liquids, glycerine and propylene glycol, and in the presence of degradation products; (3) Results: Our HPLC method performed strongly and was validated according to international guidelines. For the e-liquids tested, nicotine content levels were all higher than labelled (up to 117.9 ± 1.87% of the labelled content). While nicotine was shown to be unstable at 60 °C, it was stabilized at this temperature in the e-liquid formulations for up to 10 days; and (4) Conclusions: The HPLC method is suitable for adoption by laboratories to determine the actual content and stability of nicotine-containing products. The higher than labelled nicotine levels in e-liquids raises clinical and public health concerns

Stretchable Electronics Based on Laser Structured, Vapor Phase Polymerized PEDOT/Tosylate

The fabrication of stretchable conductive material through vapor phase polymerization of poly(3,4-ethylenedioxythiophene) (PEDOT) is presented alongside a method to easily pattern these materials with nanosecond laser structuring. The devices were constructed from sheets of vapor phase polymerized PEDOT doped with tosylate on pre-stretched elastomeric substrates followed by laser structuring to achieve the desired geometrical shape. Devices were characterized for electrical conductivity, morphology, and electrical integrity in response to externally applied strain. Fabricated PEDOT sheets displayed a conductivity of 53.1 ± 1.2 S cm−1; clear buckling in the PEDOT microstructure was observed as a result of pre-stretching the underlying elastomeric substrate; and the final stretchable electronic devices were able to remain electrically conductive with up to 100% of externally applied strain. The described polymerization and fabrication steps achieve highly processable and patternable functional conductive polymer films, which are suitable for stretchable electronics due to their ability to withstand externally applied strains of up to 100%

CrowdLoc

Determining the location of a mobile user is central to several crowd-sensing applications. Using a Global Positioning System is not only power-hungry, but also unavailable in many locations. While there has been work on cellular-based localization, we consider an unexplored opportunity to improve location accuracy by combining cellular information across multiple mobile devices located near each other. For instance, this opportunity may arise in the context of public transport units having multiple travelers. Based on theoretical analysis and an extensive experimental study on several public transportation routes in two cities, we show that combining cellular information across nearby phones considerably improves location accuracy. Combining information across phones is especially useful when a phone has to use another phone’s fingerprint database, in a fingerprinting-based localization scheme. Both the median and 90 percentile errors reduce significantly. The location accuracy also improves irrespective of whether we combine information across phones connected to the same or different cellular operators. Sharing information across phones can raise privacy concerns. To address this, we have developed an id-free broadcast mechanism, using audio as a medium, to share information among mobile phones. We show that such communication can work effectively on smartphones, even in real-life, noisy-road conditions

A simultaneous optical and electrical in-vitro neuronal recording system to evaluate microelectrode performance.

ObjectivesIn this paper, we aim to detail the setup of a high spatio-temporal resolution, electrical recording system utilising planar microelectrode arrays with simultaneous optical imaging suitable for evaluating microelectrode performance with a proposed 'performance factor' metric.MethodsTechniques that would facilitate low noise electrical recordings were coupled with voltage sensitive dyes and neuronal activity was recorded both electrically via a customised amplification system and optically via a high speed CMOS camera. This technique was applied to characterise microelectrode recording performance of gold and poly(3,4-ethylenedioxythiophene)/polystyrene sulfonate (PEDOT/PSS) coated electrodes through traditional signal to noise (SNR) calculations as well as the proposed performance factor.ResultsNeuronal activity was simultaneously recorded using both electrical and optical techniques and this activity was confirmed via tetrodotoxin application to inhibit action potential firing. PEDOT/PSS outperformed gold using both measurements, however, the performance factor metric estimated a 3 fold improvement in signal transduction when compared to gold, whereas SNR estimated an 8 fold improvement when compared to gold.ConclusionThe design and functionality of a system to record from neurons both electrically, through microelectrode arrays, and optically via voltage sensitive dyes was successfully achieved.SignificanceThe high spatiotemporal resolution of both electrical and optical methods will allow for an array of applications such as improved detection of subthreshold synaptic events, validation of spike sorting algorithms and a provides a robust evaluation of extracellular microelectrode performance