Procaine Research Articles

Spectrophotometric determination of procaine hydrochloride using oxidative coupling and cloud point extraction

A method with rapid, sensitive, accurate, and selective for estimation of local anesthetic procaine hydrochloride (PRO.HCl) is crucial, due to its bad damage to health if administrated excessively. In this work two spectrophotometric methods oxidative coupling and cloud point extraction (CPE) were utilized for determination of PRO.HCl in its standard state and pharmaceutical preparations. Method A, based on the oxidative coupling reaction using sodium hypochlorite as an oxidant and 2,5-dimethylphenol as coupling agent. The blue colored product has high absorption at 600 nm. Method B based on the CPE relying on the previous reaction, with addition of Triton X-114, after extracting the colored product, it was measured at 630 nm. Beer’s law of both methods are linear in the concentration ranges 2.50-50 µg/mL (method A) and 1.25-3.75 µg/mL (method B). The molar absorptivity coefficients of methods (A) and (B) are 4.01 x 103 and 1.34 x 104 L/mol.cm, respectively. For (method A) limit of detection and limit of quantification were calculated and found that 0.26 µg/mL and 0.87 µg/mL, respectively, while for (method B) were found to be 0.16 and 0.54 µg/mL, respectively. Both methods (A and B) are applied to evaluate PRO.HCl in pharmaceutical preparations (injection). KEY WORDS: Cloud point extraction, 2,5-Dimethylphenol reagent, Odxiative-coupling, Procaine-hydrochloride, Spectrophotometry, Triton X-114. Bull. Chem. Soc. Ethiop. 2025, 39(1), 1-13. DOI: https://dx.doi.org/10.4314/bcse.v39i1.1

ProcCluster® and procaine hydrochloride inhibit the growth of Aspergillus species and exert antimicrobial properties during coinfection with influenza A viruses and A. fumigatus in vitro.

Influenza-associated pulmonary aspergillosis is associated with high mortality rates and limited treatment options. The current standard practice involves treating each pathogen separately. However, the use of antifungal drugs can lead to serious side effects, and the presence of triazole-resistant Aspergillus strains can complicate antifungal therapy. In addition, drug-resistant influenza viruses are becoming an increasing concern in clinics. A drug that affects fungal and viral propagation could overcome these disadvantages. Thus, we conducted a study to examine the antifungal and antiviral properties of ProcCluster® and procaine hydrochloride (HCl), which are prodrugs derived from the local anesthetic procaine. Conidia of different A. fumigatus strains, A. flavus and A. terreus were treated with the test substances in a human cell-free system and antifungal properties were analyzed either by fluorescence microscopy or absorption measurements. Changes in metabolic activity and intracellular Ca2+ distribution during treatment of A. fumigatus with ProcCluster® were observed using fluorescence microscopy. In addition, antifungal and antiviral properties of ProcCluster® and procaine HCl were investigated during in vitro coinfection of lung epithelial cells with A. fumigatus and influenza A viruses (IAV). Analysis was performed by fluorescence microscopy, standard plaque assay and Western blot assay. Both substances inhibited the growth of the fungus, even when applied after germination or in the presence of purified IAV particles. ProcCluster® remained effective against triazole-resistant A. fumigatus strains. However, the addition of CaCl2 reversed the antifungal effect, indicating that ProcCluster® inhibited fungal growth by disrupting fungal Ca2+ homeostasis. Furthermore, in vitro studies showed that ProcCluster® and procaine HCl reduced the pathogen load of IAV and A. fumigatus during coinfection. Finally, the combination of ProcCluster® with the antiviral drug favipiravir exhibited increased antipathogenic activity, particularly against IAV replication. This research highlights ProcCluster® and procaine HCl as substances with anti-infective properties against various pathogens.

Dual Electrochemical Methods for Determination of Anesthetic Procaine

Procaine belongs to a type of medicine in which excessive dosage form creates cardiac problems and many allergenic reactions. Thus, continuous monitoring of this drug and its metabolite is crucial for sustainable health management during treatment. In this study, electrochemical techniques such as square wave voltammetry (SWV) and differential pulse polarography (DPP) are utilized for assaying procaine amounts in standard and pharmaceutical formulations. In SWV, the reduction of diazotized procaine gives a reduction peak at −0.05 V which is directly proportional with procaine hydrochloride concentration, whereas in DPP, the interaction of the drug with lead cation at −0.4 V is followed by the decrease in peak current of the lead cation reduction peak, which is directly proportional with the concentration of the drug. Both methods indicate high accuracy, sensitivity and precision. Linear concentration ranges of both methods are 0.0999–5.996 × 10-7 M for SWV and 0.1999–5.996 × 10-7 M for DPP. The limit of detection (LOD) and limit of quantification (LOQ) are calculated for both SWV and DPP techniques, and found that LOD equals 1.984 × 10-9 M and LOQ equals 6.611 × 10-9 M for SWV, while for (DPP) LOD and LOQ were found to be 3.519 × 10-9 M and 1.173 × 10-8 M, respectively.

Fabrication of MIL-101(Fe)-embedded biopolymeric films and their biomedical applications

AbstractThe development of wound-dressing materials with superior therapeutic effects, controlled bioactive agent release, and optimal mechanical properties is crucial in healthcare. This study introduces innovative hydrogel films designed for the sustained release of the local anesthetic drug Procaine (PC), triggered by pH changes. These films are composed of MIL-101(Fe) particles and pectin polymers. MIL-101(Fe) was chosen for its high surface area, stability in aqueous environments, and biocompatibility, ensuring low toxicity to normal cells. MIL-101(Fe)-embedded-pectin hydrogels were synthesized and characterized using Fourier-transformed infrared (FTIR) spectroscopy, thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), inductively coupled plasma (ICP) spectrometry, particle size analysis, and goniometry. Rheological analysis assessed the hydrogels’ viscoelastic behavior, and UV-spectrophotometry was utilized for drug loading and release studies. The hydrogels exhibited shear-thinning properties, enhancing shape adaptability and recovery, crucial for wound-dressing applications. Controlled drug release was achieved by maintaining the PC solution’s pH between 8.2 and 9.8 during the drug-loading step. The hydrogel film’s impact on wound healing was evaluated through an in vitro wound healing assay, and cytotoxicity was assessed using a WST-1 cell proliferation assay with human dermal fibroblast cells. Results demonstrated that pectin composites enhance cell viability and support fibroblast cell migration without adverse effects, indicating their potential for effective wound healing applications. This study highlights the potential of MIL-101(Fe)-embedded-pectin hydrogels in advancing wound care technology. Graphical Abstract MIL-101(Fe)-embedded pectin film as wound dressing

The use of a hypromellose based sorbent for a solid-phase extraction in the quantitative determination of procaine in combination drugs

Aim – to assess the selectivity and metrological characteristics of the spectrophotometric method for procaine determination in combination drugs using a solid-phase extraction sorbent based on hypromellose. Material and methods. The solid-phase extraction sorbent was obtained with hypromellose and ethyl cyanoacrylate; the procaine hydrochloride and sodium hydroxide formed the active centers. The sorbent was prepared using a standard method. The sorption capacity of the obtained sorbent samples for procaine was 10.2 ± 1.0 µg/g. For the study, we selected the combination drugs containing procaine and its salts, such as "Menovazin", "Sulfocamphocaine", and "Otolorin". The eluate optical density was registered using a SF-56 spectrophotometer (OKB SPECTR LLC) at an analytical wavelength of 292 nm in a cuvette with an optical layer thickness of 1 cm. The reference solution was a 0.1 M hydrochloric acid solution. To calculate the procaine content in the eluates, a calibration graph (dependence of eluate optical density on procaine concentration) was plotted in the concentration range of 1–20 mcg/ml. To evaluate the selectivity (specificity) of sample preparation in chromatographic separation of the combination drugs, the absorption spectra were registered in the wavelength range of 200–400 nm for eluates obtained using purified water and a 0.1 M hydrochloric acid solution. The procaine and benzocaine were identified in the eluate by the presence of absorption maxima at wavelengths of 222 and 286 nm for benzocaine, and 228 and 292 nm for procaine. For statistical processing of the experimental results and determination of metrological characteristics of the analysis method, we followed the GPM.1.1.0013 "Statistical processing of results of physical, physicochemical, and chemical tests". Results. We have demonstrated the selectivity of the spectrophotometric determination of procaine in certain combination drugs using a solid-phase extraction sorbent based on hypromellose. The selective binding of the analyzed substance with active centers in the sorbent and stepwise elution with purified water and a 0.1 M hydrochloric acid solution during solid-phase extraction eliminated the interfering effect of drug components during the UV-spectrophotometry of procaine. The use of a hypromellose based sorbent improved the metrological characteristics and reduced the systematic error of the quantitative determination method by an average of 14.4%. The proposed methodological approach using a selective sorbent might be recommended as the quality control for combination drugs containing procaine and its salts.

ProcCluster® and procaine hydrochloride inhibit the replication of influenza A virus in vitro.

Treatment of influenza A virus infections is currently limited to few direct acting antiviral substances. Repurposing other established pharmaceuticals as antivirals could aid in improving treatment options. This study investigates the antiviral properties of ProcCluster® and procaine hydrochloride, two derivatives of the local anesthetic procaine, in influenza A virus infection of A549, Calu-3 and MDCK cells. Both substances inhibit replication in all three of these cell lines in multi-cycle experiments. However, cell line-dependent differences in the effects of the substances on viral RNA replication and subsequent protein synthesis, as well as release of progeny viruses in single-cycle experiments can be observed. Both ProcCluster® and procaine hydrochloride delay endosome fusion of the virus early in the replication cycle, possibly due to the alkaline nature of the active component procaine. In A549 and Calu-3 cells an additional effect of the substances can be observed at late stages in the first replication cycle. Interestingly, this effect is absent in MDCK cells. We demonstrate that ProcCluster® and procaine hydrochloride inhibit phospholipase A2 (PLA2) enzymes from A549 but not MDCK cells and confirm that specific inhibition of calcium independent PLA2 but not cytosolic PLA2 has antiviral effects. We show that ProcCluster® and procaine hydrochloride inhibit influenza A virus infection at several stages of the replication cycle and have potential as antiviral substances.

Developing multifunctional pectin-based hydrogel for wound dressing: In silico, in vitro and in vivo evaluation

Multifunctional hydrogel wound dressing with high hemostatic, antioxidant, and self-healing activity is desirable in clinical applications. In this contribution, we developed two distinct hydrogel formulations, namely PZ and PTBA, by employing low methoxyl pectin (P), zeolite, or 2-thiobarbituric acid (TBA) for sustained release of procaine (PC) in a controlled manner up to 40 h. These hydrogel systems (PZ and PTBA) utilize dynamic reversible hydrogen bonds between the components and a metal coordination bond between carboxyl acid groups of pectin chains and Ca2+ to confer self-healing properties, as demonstrated by molecular dynamics (MD) and rheological analyses. Moreover, PZ and PTBA hydrogels possess superior antioxidant, hemostasis, biocompatibility, and antibacterial activities. The data from the mouse skin incision model and infected full-thickness skin wound model demonstrated the highest wound closure rate (wound closure area per day) was achieved by the PZ (4.72) and PTBA (4.62) groups on day 21, which was better than the control (4.2) and Kaltostat groups (4.05) (p < 0.05). PZ and PTBA’s effectiveness in wound closure and acceleration of the wound healing process, highlighting its significant potential in wound management.

Procaine induces cell cycle arrest, apoptosis and autophagy through the inhibition of the PI3K/AKT and ERK pathways in human tongue squamous cell carcinoma.

Procaine (PCA), a local anesthetic commonly used in stomatology, exhibits antitumor activity in some human malignancies. However, the precise mechanism underlying PCA activity remains unknown, and its antitumor effect in human tongue squamous carcinoma cells has not been reported. Flow cytometry and western blotting were used to assess the effects of PCA on mitochondrial membrane potential (ΔΨm), intracellular reactive oxygen species (ROS) production, cell cycle and apoptosis. The results suggested that PCA inhibits CAL27 and SCC-15 cell proliferation, and clone formation in a dose-dependent manner. CAL27 cells were more sensitive to PCA than SCC-15 cells. PCA also significantly inhibited cell migration, induced mitochondrial damage, reduced ΔΨm and increased intracellular ROS production. PCA causes G2/M cycle arrest and induces apoptosis. The possible mechanism for the inhibition of human tongue squamous carcinoma cell proliferation is through the regulation of ERK phosphorylation and PI3K/AKT-mediated signaling pathways. The results further suggested that autophagy occurs during PCA-induced apoptosis in CAL27 cells, and the addition of the autophagy inhibitor hydroxychloroquine sulfate further enhanced the sensitivity of PCA to inhibit cell proliferation, indicating that autophagy plays an important role in protecting cancer cells from apoptosis. PCA shows potential as an anticancer drug and its combination with autophagy inhibitors enhances its sensitivity.

Biopolymeric 3D printed implantable scaffolds as a potential adjuvant treatment for acute post-operative pain management

ABSTRACT Background Pain is characterized as a major symptom induced by tissue damage occurring from surgical procedures, whose potency is being experienced subjectively, while current pain relief strategies are not always efficient in providing individualized treatment. 3D printed implantable devices hold the potential to offer a precise and customized medicinal approach, targeting both tissue engineering and drug delivery. Research design and methods Polycaprolactone (PCL) and PCL – chitosan (CS) composite scaffolds loaded with procaine (PRC) were fabricated by bioprinting. Geometrical features including dimensions, pattern, and infill of the scaffolds were mathematically optimized and digitally determined, aiming at developing structurally uniform 3D printed models. Printability studies based on thermal imaging of the bioprinting system were performed, and physicochemical, surface, and mechanical attributes of the extruded scaffolds were evaluated. The release rate of PRC was examined at different time intervals up to 1 week. Results Physicochemical stability and mechanical integrity of the scaffolds were studied, while in vitro drug release studies revealed that CS contributes to the sustained release dynamic of PRC. Conclusions The printing extrusion process was capable of developing implantable devices for a local and sustained delivery of PRC as a 7-day adjuvant regimen in post-operative pain management.

Enhancing photosynthesis in cyanobacteria: Molecular docking of procaine hydrochloride with ATP synthase protein

Enhancing photosynthesis in cyanobacteria: Molecular docking of procaine hydrochloride with ATP synthase protein

Electrochemical sensor based on polypyrrole/triiron tetraoxide (PPY/Fe3O4) nanocomposite deposited from a deep eutectic solvent for voltammetric determination of procaine hydrochloride in pharmaceutical formulations

This investigation reports the electrochemical preparation of a polypyrrole/triiron tetraoxide (PPY/Fe3O4) nanocomposite from deep eutectic solvents (DESs), and their application as novel sensor electrodes to determine certain pharmaceutical formulations using cyclic voltammetry (CV). The modified polypyrrole/Fe3O4 nanocomposite was characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy. These techniques confirmed the incorporation of Fe3O4 into the polypyrrole composite. Cyclic voltammetry and electrochemical impedance spectroscopy (EIS) indicated that PPY/Fe3O4 shows higher redox currents and greater electrical conductivity with procaine hydrochloride than other pharmaceutical formulations (ascorbic acid, diclofenac, losartan potassium, adiphenine hydrochloride, and metformin hydrochloride). Factors that could influence the determination of procaine hydrochloride, including pH, temperature, scan rate, concentration of drug, stability, and reproducibility, have all been optimized. Under optimal conditions, the calibration curve shows a linear relationship between oxidation peak current and procaine hydrochloride concentrations (between 0.005 and 0.3 mol/L), with an R2 of 0.9943. The limit of detection (LOD) was 0.0024 mol/L and the limit of quantification (LOQ) was 0.0079 mol/L. The modified sensor (PPY/Fe3O4) constructed in this study was successfully used for the determination of procaine hydrochloride drug concentrations in a procaine-penicillin pharmaceutical product.

Multifunctional Hydrogels Based on Cellulose and Modified Lignin for Advanced Wounds Management.

Considering the complex process of wound healing, it is expected that an optimal wound dressing should be able to overcome the multiple obstacles that can be encountered in the wound healing process. An ideal dressing should be biocompatible, biodegradable and able to maintain moisture, as well as allow the removal of exudate, have antibacterial properties, protect the wound from pathogens and promote wound healing. Starting from this desideratum, we intended to design a multifunctional hydrogel that would present good biocompatibility, the ability to provide a favorable environment for wound healing, antibacterial properties, and also, the capacity to release drugs in a controlled manner. In the preparation of hydrogels, two natural polymers were used, cellulose (C) and chemically modified lignin (LE), which were chemically cross-linked in the presence of epichlorohydrin. The structural and morphological characterization of CLE hydrogels was performed by ATR-FTIR spectroscopy and scanning electron microscopy (SEM), respectively. In addition, the degree of swelling of CLE hydrogels, the incorporation/release kinetics of procaine hydrochloride (PrHy), and their cytotoxicity and antibacterial properties were investigated. The rheological characterization, mechanical properties and mucoadhesion assessment completed the study of CLE hydrogels. The obtained results show that CLE hydrogels have an increased degree of swelling compared to cellulose-based hydrogel, a better capacity to encapsulate PrHy and to control the release of the drug, as well as antibacterial properties and improved mucoadhesion. All these characteristics highlight that the addition of LE to the cellulose matrix has a positive impact on the properties of CLE hydrogels, confirming that these hydrogels can be considered as potential candidates for applications as oral wound dressings.

The Local Anaesthetic Procaine Prodrugs ProcCluster® and Procaine Hydrochloride Impair SARS-CoV-2 Replication and Egress In Vitro.

As vaccination efforts against SARS-CoV-2 progress in many countries, there is still an urgent need for efficient antiviral treatment strategies for those with severer disease courses, and lately, considerable efforts have been undertaken to repurpose existing drugs as antivirals. The local anaesthetic procaine has been investigated for antiviral properties against several viruses over the past decades. Here, we present data on the inhibitory effect of the procaine prodrugs ProcCluster® and procaine hydrochloride on SARS-CoV-2 infection in vitro. Both procaine prodrugs limit SARS-CoV-2 progeny virus titres as well as reduce interferon and cytokine responses in a proportional manner to the virus load. The addition of procaine during the early stages of the SARS-CoV-2 replication cycle in a cell culture first limits the production of subgenomic RNA transcripts, and later affects the replication of the viral genomic RNA. Interestingly, procaine additionally exerts a prominent effect on SARS-CoV-2 progeny virus release when added late during the replication cycle, when viral RNA production and protein production are already largely completed.

Application of Infrared Spectroscopy and X-Ray Powder Diffractometry for Assessment of the Qualitative Composition of Components in a Pharmaceutical Formulation

A qualitative assessment of a new four-component pharmaceutical composition has been carried out using the methods of infrared spectroscopy and X-ray powder diffractometry. Qualitative characteristics for the identification of mixture components by absorption bands in infrared spectra and characteristic peaks by positions on the scattering angle 2θ scale in diffractograms were determined. It was experimentally confirmed that the quantitative content of benzocaine and procaine hydrochloride in the mixture without diclofenac sodium decreased by two times compared to their content in the mixture with it. Original infrared spectra and X-ray diffractograms of the new pharmaceutical composition with diclofenac sodium, which can be used for its identification, are presented.

Latrogenic Pneumothorax Caused by Thoracic Puncture Secondary to Anti-aging Medicine

Introduction: Pneumothorax is defined as air in the pleural cavity, the iatrogenic cause happens after invasive procedures as thoracic needle aspiration, central line placement, pacemaker placement, etc. Nevertheless, it is possible to be found in non-medical procedures, such as alternative medicine, more specifically acupuncture. There are medications used against aging that FDA has warned to be used only in its first objective, an example is procaine hydrochloride. Case: A 63 y/o female, Mexico City resident, with anxiety, came to a follow-up appointment for an aging cohort, where CT, PFT, and laboratories are made for pulmonary healthy subjects to investigate normal lung aging and how other environmental factors can affect the lungs; at physical examination, we did not find any pleuropulmonary syndrome, but in the CT a left Iatrogenic pneumothorax was found; we re-asked for antecedents and she described that 15 days before the date she had 2 punctures in the middle clavicular line to apply procaine hydrochloride as an anti-aging treatment. Discussion: There is diverse evidence of adverse effects associated with acupuncture, and even if pneumothorax has a small percentage of incidence, in some cases it can be severe and can even cause fatalities. Conclusion: The pneumothorax in this case was iatrogenic due to the thoracic puncture for an anti-aging treatment, with a total resolution with conservative treatment, however we as health professionals have the responsibility to inform our patients that initiatives of administration ways can cause important complications.

In situ enrichment and determination of 6 kinds of caine-type anesthetics in cosmetics and rat serum by thin layer chromatography-Raman spectroscopy

A simple, economical and selective method has been established for simultaneous detection of 6 kinds of caine-type anesthetics in cosmetics and rat serum by in situ enrichment thin layer chromatography (TLC) and Raman spectroscopy. The target caine-type anesthetics, procaine hydrochloride (Pro), tetracaine hydrochloride (Tet), dibucaine (Dib), mepivacaine hydrochloride (Mep), lidocaine hydrochloride (Lid) and ropivacaine hydrochloride (Rop), were separated by TLC. The original spots (or position of Rf equal to that of the standard) of anesthetics on TLC plates were in situ enriched into much smaller ones driven by solvent from different directions, and followed by Raman measurement for quanlitative and quantitative analysis, resulting in the improvement of sensitivity and selectivity. Optimization and standardization of the experimental conditions, the composition and proportion of developing solvent, were conducted. Thus a robust and reliable approach which enabled effective separation, accurate identification and quantification has been developed with the lowest detectable amounts of 0.4, 0.2, 1.2, 1, 1 and 1 μg for Pro, Tet, Dib, Mep, Lid and Rop, respectively. The established method was successfully applied in anesthetics analysis in cosmetics (essence, cream and gel) and rat serum without complex sample pretreatment processes, and the results were verified by HPLC. It turned out that the in situ enrichment TLC-Raman technique was feasible and effective for separation and determination of 6 caine-type anesthetics in biological samples and cosmetics, and would have good prospects for on-site qualitative screening of prohibited goods and adulterants.

Electrocatalytic barium-oxide decorated MWCNT amperometric sensor for the quantification of anesthetic drug Procaine

Procaine hydrochloride (P.HCl) is one of the earliest and most well-established local anesthetic drugs used in medicine. Though it is employed frequently for effective clinical nerve blocks during surgeries, its immoderate administration has often shown reports of systemic toxicity. To prevent such repercussions, developing a sensor for the drug is crucial to enable real-time monitoring of the drug and assist in quality control procedures during its industrial preparations. Thus, in this work, we have fabricated a simple yet highly selective and sensitive amperometric sensor for P.HCl detection based on a Barium-oxide multi-wall carbon nanotube-modified carbon paste electrode (BaO-MWCNT/CPE). Herein, we have adopted a novel approach devoid of sophisticated procedures and pretreatments for rapidly determining P.HCl. Furthermore, experimental conditions, including supporting electrolytes, pH, and scan rate, were optimized to achieve a well-defined P.HCl anodic peak current at 631 mV, which is lower than the previously reported peak potentials, indicating an advantage of reduced overpotential. Besides, a striking 66-fold rise in current responsiveness to P.HCl was achieved upon modification with BaO-MWCNT. Such an intense signal enhancement upon electrode modification compared to bare CPE was due to the strong electrocatalytic feature of BaO-MWCNT, which was verified using surface morphology studies with scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Additionally, the charge transfer kinetics analyzed via electrochemical impedance spectroscopy (EIS) justified the enhancement of electrocatalytic activity upon electrode modification. The developed sensor exhibited a remarkable analytical performance over a wide linear dynamic range of 2.0–100.0 µM with a detection limit of 0.14 µM. Moreover, a significant merit of this sensor is its excellent selectivity towards P.HCl even in the presence of various common interferants. Finally, the versatility of the sensor was further validated by implementing it for the trace analysis of urine and blood serum real samples.

Spectrophotometric Determination of Procaine Hydrochloride in pharmaceutical preparations Via Oxidative Coupling Reaction

A simple, reliable and sensitive spectrophotometric method for the determination of trace amount of procaine hydrochloride in pure and in pharmaceutical preparations (injections) has been developed. The method is based on the oxidative coupling reaction of procaine hydrochloride with phenothiazine and in the presence of ferric nitrate to form a green-water-soluble dye, which is stable and has a maximum absorption at 610 nm. A graph of absorbance versus concentration shows that beer's law is obeyed over the concentration range of 50-2000 µg of procaine hydrochloride in a final volume of 25 ml or (2-80 µg.ml-1) with a molar absorpitivity of 5.51 x 103 L.mol-1.cm-1, a Sandell sensitivity of 4.28 x 10-2 µg.cm-2, a relative error was less than 1.98% and a relative standard deviation was better than 1.72% depending on the concentration. The optimum conditions for full color development are described and the proposed method was applied satisfactorily to pharmaceutical preparations containing procaine Hydrochloride using standard addition method.

Evaluation of Cytotoxic Activity of Epigenetic Drugs in Oesophageal Squamous Cell Carcinoma

Oesophageal squamous cell carcinoma (OESCC) is a poor prognosis cancer with current treatments demonstrating limited efficacy. Recently, the field of epigenetics has gained equal importance to that of genetics in cancer, including in oesophageal cancer. The increasing number of epigenetic drugs is driving the need to identify the most efficacious and potent of these drugs in various cancers. This study investigated both the metabolic activity and importantly, the long-term cytotoxic effects of different families of epigenetic drugs including DNA methyltransferase inhibitors (DNMTi: azacitidine, 5-aza-2ʹ-deoxycytidine, 5-fluoro-2ʹ-deoxycytidine, RG108, procaine hydrochloride, zebularine), histone deacetylase inhibitors (HDACi: valproic acid, panobinostat, vorinostat, belinostat, romidepsin, RGFP966 and santacruzamate A) and bromodomain and extra-terminal motif inhibitors (BETi: JQ1, OTX015, I-BET151A and I-BET762) in OESCC cells (KE-8 and KYSE-450) as well as non-neoplastic oesophageal epithelial cells (HET-1A). Effects on metabolic activity were measured using the MTT bio-reduction assay, while cytotoxic effects were assessed using the long-term clonogenic assay. Dose-dependent effects were observed with specific drugs from all three classes of epigenetic drugs. OESCC cells were most vulnerable to the FDA approved drugs (valproic acid, panobinostat, vorinostat, belinostat and romidepsin) in both the MTT bio-reduction and clonogenic assays. Interestingly, the non-neoplastic HET-1A epithelial cells demonstrated resistance to some DNMTi and HDACi drugs at concentrations that were cytotoxic to OESCC. Thus, our findings have identified a subset of epigenetic drugs that can impair the metabolic activity of OESCC and importantly, are cytotoxic. This may aid in the design of future therapeutic regimes for treatment of this drug resistant cancer.

FeS2 nanosheets-H2 O2 -NaHCO3 chemiluminescence method for procaine hydrochloride determination.

FeS2 nanosheets (NSs) were produced and exploited as a new catalyst for a chemiluminescence (CL) reaction. The characterization of FeS2 NSs was performed using spectroscopic methods. In this regard, transmission electron microscopy images showed that FeS2 NSs have a length of ~0.5-1μm. The direct optical band gap energy of FeS2 NSs was found to be 3.45 eV. Prepared FeS2 NSs were used to catalyze the NaHCO3 -H2 O2 CL reaction. It was found that procaine hydrochloride (PCH) could reduce the intensity of the FeS2 NSs-NaHCO3 -H2 O2 CL reaction so, with increasing PCH concentrations, the intensity of light emission decreased. Therefore, a simple and sensitive method was introduced to measure PCH with a linear range expanded from 1.00 × 10-6 to 1.00 × 10-3 mol L-1 and an 8.32 × 10-7 mol L-1 limit of detection. Studies related to the effect of foreign species and reaction mechanisms were performed. The application of the approach was verified by quantifying the PCH in the injection.