Development of a sustainable procedure for smartphone-based colorimetric determination of benzalkonium chloride in pharmaceutical preparations.

A sustainable procedure offering green, simple, and rapid analysis was developed to determine benzalkonium chloride (BKC) in pharmaceutical preparations. The determination using smartphones was based on the ion pair colorimetric reaction with bromothymol blue (BTB), which produces a yellow color. The intensity of the product color, which is proportional to the concentration of BKC, was detected and evaluated using a smartphone camera and an image processing application. The procedure was performed in a microliter and was rapidly detected within 1 min after incubation. This offered high throughput at 28 samples per well plate in duplicate. Linear calibration, which was a plot of BKC concentrations and relative red intensities, was in the range of 2.0-24.0 µg/mL with an R2 of 0.997. The limits of detection (LOD) and quantitation (LOQ) were 1.0 and 3.2 µg/mL, respectively. This work was successful in applying it to pharmaceutical materials, disinfectant products, and pharmaceutical products containing BKC. It was discovered that the concentrations of BKC as an active ingredient in pharmaceutical materials were 82% w/v, whereas those in disinfectant products ranged from 0.4 to 2.1% w/v. In pharmaceutical products, ophthalmic drops and nasal sprays contain BKC as preservatives in the 0.01-0.02, and the 0.02% w/v, respectively. The results obtained by the proposed procedure compared with a reference titration method showed no significant differences at a 95% confidence level with 1.2-3.4% RSDs. This promotes the efficiency of pharmaceutical preparations regarding infection prevention and control by ensuring that available disinfectants contain a sufficient concentration of BKC. Additionally, this improves the efficiency of pharmaceutical preparations for quality control of pharmaceutical products by ensuring that the available preservatives maintain a sufficient concentration throughout the lifespan of the products.

Pharmaceutical Incompatibility of Lubricating Gel Formulation Reduces Antibacterial Activity of Chlorhexidine Gluconate: In Vitro Study in Northern Thailand.

Chlorhexidine gluconate (CHG) is a cationic disinfectant. The positive charge of CHG molecules binds to phospholipid's negative charge in bacterial cell walls, causing membrane disruption. The in vitro kinetic physical, chemical and biological incompatibilities of nine lubricating gels with 1% w/v CHG were investigated. Five containing anionic thickener, two containing nonionic thickener, and two containing cationic thickener were collected from hospitals in northern Thailand. All the anionic and nonionic lubricating gels significantly reduced (p < 0.05) the CHG amount after 5 min of exposure time from 12.54% to 54.99%, respectively. In contrast, the amount of CHG exposed with cationic lubricating gels was maintained. Antibacterial activity was significantly reduced to a 1.17-4.33 log10 reduction for Staphylococcus aureus ATCC25923 and a 1.07-3.52 log10 reduction for Escherichia coli ATCC25922 after 5 min exposure to all anionic and nonionic lubricating gels. In contrast, the two cationic lubricating gels maintained the antibacterial activity of the CHG solution (5.69 ± 0.14 and 5.45 ± 0.17 log10 reduction). The results suggest that anionic and nonionic thickeners in lubricating gel formulations may neutralize the positive charge and reduce the antibacterial activity of CHG, reducing its effectiveness as a disinfectant.

Sustainable Downscaled Catalytic Colorimetric Determination of Manganese in Freshwater Using Smartphone-Based Monitoring Oxidation of 3,3',5,5'-Tetramethylbenzidine by Periodate.

A sustainable downscaled procedure using smartphone-based colorimetric determination of manganese (Mn(II)) was developed. This novel Mn(II) determination procedure is proposed using a simple, available microwell-plate platform and a smartphone as a detector. This approach is based on the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by periodate using Mn(II) as a catalyst. The catalytic kinetics of Mn(II) under different conditions was investigated to determine the optimum condition where the different catalytic activities of various concentrations of Mn(II) evince. Under the optimum condition, the bluish-green product of oxidized TMB, proportioned to the concentration of Mn(II), was monitored using a smartphone camera, and the color signals were processed using ImageJ Software. The developed procedure showed great selectivity and sensitivity as linearity ranged from 1.8 × 10-6 to 4.6 × 10-5 M (0.1 to 2.5 µg/mL). The limits of detection and quantitation were 3.6 × 10-6 and 1.1 × 10-5 M (0.2 and 0.6 µg/mL), respectively. The determination of Mn(II) in freshwater samples was demonstrated to assess environmental water quality as an initial model to more easily promote water management according to the United Nations Sustainable Development Goals (UN-SDGs). The intensity of the red could be successfully applied to evaluate Mn(II) in canals and river water with no significant differences compared with the reference method of Inductively Coupled Plasma Optical Emission Spectrometry at a confidence level of 95%.

Antibacterial Activity against Foodborne Pathogens and Inhibitory Effect on Anti-Inflammatory Mediators' Production of Brazilin-Enriched Extract from Caesalpinia sappan Linn.

Caesalpinia sappan L. heartwood was collected from Mae Chaem District, Chiang Mai Province, Thailand. Crude extracts were prepared by Soxhlet's extraction using 50, 60, and 70% of ethanol (EtOH) at 50, 60, and 70 °C, and the brazilin content was measured using reversed-phase high performance liquid chromatography (RP-HPLC). The antibacterial activity against foodborne pathogens and anti-inflammatory aspects were investigated. C. sappan, prepared from 70% EtOH at 70 °C (E70T70), significantly (p < 0.05) exhibited the highest amount of brazilin (7.90 ± 0.50% w/w). All extracts were investigated for anti-inflammatory activity through an inhibition effect on nitric oxide (NO) and inducible nitric oxide synthase (iNOS) production in RAW264.7 mouse macrophage cells. The inhibitory effect on cyclooxygenase-2 (COX-2) production in HT-29 and HCT116 was also studied. All the extracts inhibited NO, iNOS, and COX-2 production induced by combined lipopolysaccharide and interferon-γ, especially E70T70, indicating the highest inhibition effect among other extracts. Additionally, E70T70 was selected to determine the antibacterial activity against foodborne pathogens, including Staphylococcus aureus, Escherichia coli, Salmonella enteritidis, and Vibrio parahaemolyticus. The result showed that 200 µg/mL extract reduced all test pathogens 100% at 24 h. These results suggested the potential of using C. sappan L. extract as a natural preservative in food and a natural active pharmaceutical ingredient.

Local Wisdom and Diversity of Medicinal Plants in Cha Miang Forest in Mae Kampong Village, Chiang Mai, Thailand, and Their Potential for Use as Osteoprotective Products.

"People-Forest-Miang" communities are villages located in the cultivated area of Camellia sinensis var. assamica, or Cha Miang, in northern Thailand. Cha Miang forests are a form of agriculture relying on forest-rich bioresources. This study focuses on a survey of the diversity of medicinal plants used by "People-Forest-Miang" communities in Mae Kampong Village, Chiang Mai, Thailand. The results demonstrated that 73 species of medicinal plants were used to prevent and treat various ailments. The highest number of species (30.14%) was used for musculoskeletal system disorders, followed by digestive system disorders (21.92%) and unspecified medicinal disorders (15.07%). The alkaline phosphatase (ALP) is the most widely recognized biochemical marker for osteoblast activity. The ALP activity of ethanol and deionized water extracts of the nine selected medicinal plants used for musculoskeletal system disorders were examined in the MG63 cell line. The results showed that the numerous water extracts, including MKP1, MKP2, MKP5, MKP6, MKP7, MKP8, and MKP9, and the ethanolic extracts-namely, MKP2, MKP3, MKP7, and MKP9-significantly increased ALP activity in the MG-63 cell line. The findings indicate that some medicinal plants may be further studied for active chemicals and developed as natural active pharmaceutical ingredients for osteoprotective products.

Enhancement of the Colorectal Chemopreventive and Immunization Potential of Northern Thai Purple Rice Anthocyanin Using the Biotransformation by ß-Glucosidase-Producing Lactobacillus.

This study aimed to study the biotransformation of indigenous northern Thai purple rice using ß-glucosidase-producing Lactobacillus (BGPL) to increase the content of bioactive anthocyanin for colorectal chemoprevention and immunization. BGPL, namely, Lactobacillus FR 332, was first isolated from Thai fermented foods. Indigenous northern Thai purple rice, namely, Khao' Gam Leum-Phua (KGLP), was selected to study bioactive anthocyanin using biotransformation by L. plantarum FR332 according to the highest amounts of cyanidin-3-glucoside. The determination of anthocyanin quantities revealed that the highest cyanidin was detected after 12 h of biotransformation, corresponding to the highest ß-glucosidase activity of L. plantarum FR332 and a decrease in cyanidin-3-glucoside. The anthocyanin extract, after 12 h of biotransformation, exhibited the most potent in vitro antioxidative activity. Additionally, it showed potent anti-inflammatory activity by inhibiting cyclooxygenase-2 (COX-2), nitric oxide, and inducible nitric oxide synthase (iNOS) production in interferon-γ-stimulated colon adenocarcinoma (HT-29) cells without exerting cytotoxicity. Moreover, it also showed a potent inhibitory effect on proinflammatory cytokine interleukin-6 (IL-6) secretion and an induction effect on anti-inflammatory cytokine IL-10 secretion. These documents highlight the potential to be used of the anthocyanin extract after 12 h of biotransformation by L. plantarum FR332 as a natural active pharmaceutical ingredient (NAPI) for colorectal chemoprevention and immunization.

A Simple Minimized System Based on Moving Drops for Antioxidant Analysis Using a Smartphone.

In this paper, a novel antioxidant analysis is proposed using a simple minimized device based on moving drops as solution handling and a smartphone as a detector. This approach is based on the colorimetric determination of the scavenging activity against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•), expressed as the half-maximal inhibitory concentration (IC50), vitamin C equivalent antioxidant capacity (VCEAC), and Trolox equivalent antioxidant capacity (TEAC). A small drop of the positive control or the samples moves by eluting an ethanol drop down by the force of gravity to react with a DPPH• drop in the detection zone. The color change of DPPH• is monitored by a smartphone camera, and the color signals are processed using Adobe Photoshop software. The magenta-to-yellow ratio was successfully applied to evaluate the percentage of DPPH• inhibition with no significant difference compared with the reference spectrophotometric method at a confidence level of 95%. The total phenolic content (TPC) was measured using the Folin-Ciocalteu assay. An application to Miang (fermented tea leaf extract) showed the consonant relationship between the scavenging activity of DPPH• and TPC.

Development of HPLC Method for Catechins and Related Compounds Determination and Standardization in Miang (Traditional Lanna Fermented Tea Leaf in Northern Thailand).

High performance liquid chromatography (HPLC) for catechins and related compounds in Miang (traditional Lanna fermented tea leaf) was developed to overcome the matrices during the fermentation process. We investigated a variety of columns and elution conditions to determine seven catechins, namely (+)-catechin, (-)-gallocatechin, (-)-epigallocatechin, (-)-epicatechin, (-)-epigallocatechin gallate, (-)-gallocatechin gallate, (-)-epicatechin gallate, as well as gallic acid and caffeine, resulting in the development of reproducible systems for analyses that overcome sample matrices. Among the three reversed-phase columns, column C (deactivated, with extra dense bonding, double endcapped monomeric C18, high-purity silica at 3.0 mm × 250 mm and a 5 µm particle size) significantly improved the separation between Miang catechins in the presence of acid in the mobile phase within a shorter analysis time. The validation method showed effective linearity, precision, accuracy, and limits of detection and quantitation. The validated system was adequate for the qualitative and quantitative measurement of seven active catechins, including gallic acid and caffeine in Miang, during the fermentation process and standardization of Miang extracts. The latter contain catechins and related compounds that are further developed into natural active pharmaceutical ingredients (natural APIs) for cosmeceutical and nutraceutical products.

Anthocyanin Profile, Antioxidant, Anti-Inflammatory, and Antimicrobial against Foodborne Pathogens Activities of Purple Rice Cultivars in Northern Thailand.

Five glutinous purple rice cultivars and non-glutinous purple rice cultivated in different altitudes in the north of Thailand were collected. The samples were extracted using ethanol and determined for anthocyanins using HPLC. The total phenolic content (TPC), total flavonoid content (TFC), and the antioxidant, anti-inflammatory, and antimicrobial activities against foodborne pathogens were investigated. The highland glutinous cultivar named Khao' Gam Luem-Phua (KGLP) extract had significantly high levels of cyanidin 3-O-glucoside, peonidin 3-O-glucoside, delphinidin 3-O-glucoside, TPC, and TFC, as well as exerting a potent antioxidant activity through ABTS assay (524.26 ± 4.63 VCEAC, mg l-ascorbic-ascorbic/g extract), lipid peroxidation (IC50 = 19.70 ± 0.31 µg/mL), superoxide anions (IC50 = 11.20 ± 0.25 µg/mL), nitric oxide (IC50 = 17.12 ± 0.56 µg/mL), a suppression effect on nitric oxide (IC50 = 18.32 ± 0.82 µg/mL), and an inducible nitric oxide synthase production (IC50 = 23.43 ± 1.21 µg/mL) in combined lipopolysaccharide-interferon-γ-activated RAW 264.7 murine macrophage cells. Additionally, KGLP also exhibited antimicrobial activity against foodborne pathogens, Staphylococcus aureus, Escherichia coli, Salmonella Enteritidis, and Vibrio parahaemolyticus. These results indicate that Thai glutinous purple rice cultivated on the highland could be a potent natural source of antioxidants, anti-inflammatories, and antimicrobial agents for use as a natural active pharmaceutical ingredient in functional food and nutraceutical products.

Cost-Effective Modern Chemical Sensor System for Soil Macronutrient Analysis Applied to Thai Sustainable and Precision Agriculture.

A modern chemical sensor system (M-CSS) was developed for the cost-effective chemical analysis of Thai precision and sustainable agriculture (TPSA), which is suitable in rural Thailand and elsewhere. The aim of this study was to achieve precision and sustainable agriculture (P-SA). The M-CSS functions according to the International Union of Pure and Applied Chemistry (IUPAC) definition and incorporates information and communication technologies (ICTs). The developed chemical sensor in the M-CSS is based on a colorimetric determination by a smart device/smartphone. Additionally, the preparation of soil samples was investigated. Soil samples of optimal conditions were extracted using an acid extractant in the ratio of one to two (extract to soil sample). Then, phosphate-phosphorous and potassium were detected with the M-CSS, which showed an excellent correlation with the standard reference methods. Interestingly, it is noteworthy that the at-site analysis of the developed method could detect a greater nitrate-nitrogen content than that of the standard reference method. The developed cost-effective analysis for the plant macronutrient content in the soil, including nitrate-nitrogen, phosphate-phosphorous, and potassium, was demonstrated for organic vegetable farms at the real P-SA research site in Northern Thailand. The obtained results can guide the management of the application of fertilizers. The proposed M-CSS exhibited the potential to be used for at-site soil macronutrient analysis and represents the starting point of Thai precision and sustainable agriculture (TPSA).

Antioxidant Activity and Anti-Photoaging Effects on UVA-Irradiated Human Fibroblasts of Rosmarinic Acid Enriched Extract Prepared from Thunbergia laurifolia Leaves.

The current study investigated the inhibiting effect on reactive oxygen species (ROS), reactive nitrogen species (RNS), and matrix metalloproteinase-1 (MMP-1) production in a cell-based study of standardized rosmarinic acid enriched extract (SRAEE) prepared from Thunbergia laurifolia leaves. HPLC chromatogram revealed that rosmarinic acid is a major component in prepared SRAEE, followed by caffeic acid. SRAEE exhibited antioxidant activity both in vitro and cell-based studies. SRAEE showed scavenging effects on nitric oxide and superoxide anion and inhibition effects on lipid peroxidation in vitro. SRAEE also inhibited ROS and MMP-1 production in normal human dermal fibroblast cells induced by H2O2 and UVA, respectively, without exerted cytotoxicity. Additionally, collagen degradation was protected by SRAEE induced by UVA. Nitric oxide and inducible nitric oxide synthase (iNOS) productions were also inhibited by SRAEE in RAW264.7 mouse macrophage cells induced by combined lipopolysaccharide (LPS)-interferon-γ (IFN-γ). The results indicated that SRAEE is a potential candidate as a natural pharmaceutical active ingredient for cosmeceutical product application.

Renewable magnetic ion-selective colorimetric microsensors based on surface modified polystyrene beads.

Magnetic ion-selective colorimetric microspheres based on surface modification of polystyrene beads (0.8 µm diameter) are reported for the first time. The common components of ion-selective optode sensing (chromoionophore, ion-exchanger and ionophore) and magnetic nanoparticles are adsorbed onto the surface of the polystyrene particles using a simple mixed solvent method. The average diameter of the magnetic microspheres is evaluated by dynamic light scattering as 0.79 ±â€¯0.06 µm. The reversible microsensors are circulated by flow and accumulated at a single spot by an applied magnet to become observable by digital camera. Hue signals are extracted from the recorded images to quantify the ratio of protonated and deprotonated form of the chromoionophore, which is the basis for optode response. The resulting magnetic microsensors respond to K+ with excellent selectivity over the range of 10-6 M to 10-2 M and a response time of t99 < 2.6±0.5 min above 10-5 M. The use of solvatochromic dyes as pH independent transducers was not successful in this application.

A simple platform with moving drops for downscaling chemical analysis incorporating smartphone detection.

A simple cost-effective device for downscaling chemical analysis with microliter-scale dropwise handing and smartphone detection is proposed. The platform was made from easily available materials. Drops of constant volume of analyte and reagent were placed onto a channel then moved by gravity force to mix and react with each other. The color change due to reaction was monitored with a smartphone. Assays of iron, copper and phosphate employing the platform were demonstrated with 1,10-phenanthroline, bicinchoninic acid and molybdate reagents, respectively. Kinetic study was also demonstrated for this simple device.