อุปกรณ์การวิเคราะห์บนกระดาษด้วยระบบของไหลจุลภาคสำหรับตรวจหายาปนปลอม ในสมุนไพรและอาหารเสริม Microfluidic Paper-based Analytic Device (µPAD) for Detection of Adulterated Drugs in Herbal and Dietary Supplements

บทคัดย่อ อุปกรณ์การวิเคราะห์บนกระดาษด้วยระบบของไหลจุลภาคประดิษฐ์ขึ้นโดยการสร้างกระดาษให้มีลวดลายซึ่งประกอบด้วยช่องไหลที่มีคุณสมบัติชอบน้ำ (หรือบริเวณโซนทดสอบ) คั่นด้วยขอบเขตที่มีคุณสมบัติไม่ชอบน้ำเพื่อควบคุมทิศทางการไหล คุณสมบัติการซึมน้ำและความพรุนของกระดาษเอื้อให้ของไหลไหลผ่านไปตามช่องโดยอาศัยเพียงคะปิลลารีแอกชัน อุปกรณ์กระดาษที่มีการออกแบบอย่างเหมาะสมสามารถนำมาประยุกต์ใช้ในงานวิเคราะห์สาขาต่าง ๆ บทความนี้นำเสนอภาพรวมโดยสังเขปเกี่ยวกับแนวทางการพัฒนาอุปกรณ์การวิเคราะห์บนกระดาษ ครอบคลุมการเลือกชนิดกระดาษ วิธีการสร้างอุปกรณ์และเทคนิคการตรวจวัดสารที่นิยมใช้ เน้นตัวอย่างของการพัฒนาอุปกรณ์เพื่อตรวจหายาแผนปัจจุบันปนปลอมในสมุนไพรและอาหารเสริม อุปกรณ์กระดาษมีข้อดีหลายประการทั้งด้านความประหยัดของต้นทุน ใช้สารเคมีปริมาณน้อยที่ระดับจุลภาค เป็นมิตรต่อสิ่งแวดล้อม ความสะดวกในการใช้งานและความรวดเร็ว คำสำคัญ: อุปกรณ์การวิเคราะห์บนกระดาษด้วยระบบของไหลจุลภาค, ยาปนปลอม, สมุนไพรและอาหารเสริม Abstract The microfluidic paper analytical device (µPAD) is fabricated by creating a patterned paper consisting of hydrophilic flow channels (or assay zones) separated by hydrophobic boundaries to control the flow direction. The wicking property and the porosity of paper facilitate the passive flow of fluids through the channel via capillary action. A well-designed µPAD can be applied in various analytical fields. This paper offers a brief review of the approaches for µPAD development, including the selection of paper types, design and fabrication method, and detection techniques commonly used, emphasizing the example of µPAD development for the detection of adulterated drugs in herbal and dietary supplements. Several advantages of µPAD are cost savings, the use of small amounts of reagent at the micro level, environmental friendliness, ease of use, and speed. Keywords: microfluidic paper-based analytic device (µPAD), adulterated drugs, herbal and dietary supplement

Colorimetric paper-based device for rapid screening of orlistat in weight loss supplements

The colorimetric paper-based device using lipase inhibition assay was developed for rapid and visual detection of orlistat in weight loss supplements. The paper device with five circular detection zones was simply fabricated from filter paper No 1 using a low-cost paper craft puncher with a design of a flower-like shape. The enzymatic reaction on the detection zone employed a small volume of a substrate, a-naphthyl acetate, a sample, and a lipase enzyme. After incubation, the Fast Blue B solution was used as a chromogenic reagent. The decrease in purple color can be observed by the naked eye, in the presence of orlistat. Under optimized conditions, the paper device showed satisfactory sensitivity and selectivity. The device was applied for rapid screening of orlistat in weight loss supplements and the results agreed with those obtained from TLC analysis

Preparation and characterization of N-benzyl-N,O-succinyl chitosan polymeric micelles for solubilization of poorly soluble non-steroidal anti-inflammatory drugs

Purpose: To investigate the solubilization of poorly water-soluble non-steroidal  anti-inflammatory drugs (NSAIDs) in N-benzyl-N,O-succinyl chitosan (BSCS)  polymeric micellesMethods: BSCS was synthesized by reductive amination and succinylation,  respectively. NSAIDs; meloxicam (MX), piroxicam (PRX), ketoprofen (KP) and indomethacin (IND) were entrapped in the hydrophobic inner cores by evaporation method. The effects of drug structure on loading efficiency, particle size and surface charge of micelles were investigated.Results: The critical micelle concentration of BSCS micelles was 0.0385 mg/mL and cytotoxicity on Caco-2 cells depends on the polymer concentration (IC50 = 3.23 ± 0.08 mg/mL). BSCS micelles were able to entrap MX, PRX, KP and IND and also improve the solubility of drugs. Drug loading efficiency was highly dependent on the drug molecules. The drug loading capacity of these BSCS micelles was in the following rank order: KP (282.9 μg/mg) > PRX (200.8 μg/mg) > MX (73.7 μg/mg) > IND (41.2 μg/mg). The highest loading efficiency was observed in KP-loaded BSCS micelles due to the attractive force between phenyl groups of KP and benzyl groups of the polymer. Particle size and surface charge were in the range of 312 - 433 nm and -38 to -41 mV, respectively.Conclusion: BSCS copolymer presents desirable attributes for enhancing the  solubility of hydrophobic drugs. Moreover, BSCS polymeric micelles might be beneficial carrier in a drug delivery system.Keywords: BSCS, polymeric micelles, solubilization, non-steroidal anti-inflammatory drug

Synthesis of N-vinylpyrrolidone/Acrylic acid nanoparticles for drug delivery: Method optimization

There are various approaches to deliver therapeutic agents to the preferred target. Polymeric nanoparticles were found to have pleasing suitability as a drug carrier. The goal of this research was to optimize the synthesis method to obtain the desirable %yield and particle properties of the new biocompatible polymer-based nanoparticles. The non-toxic polymer, N-vinyl pyrrolidone (NVP) and a widely used hydrophilic biocompatible acrylic acid (AA) monomer were used to form the drug nanocarriers. The synthesis method was optimized by changing the types of initiator (KPS or V50) and the monomers molar ratio (NVP:AA). It was found that by varying both the monomer molar ratio and the type of reaction initiator, did not have significant effect on the physicochemical characteristics of the nanocarriers. The FTIR spectra of all products exhibited the peaks of carboxylic acid, carbonyl, and tertiary amine functional group vibration. The particle size of the nanocarriers was in the range of 173.6 ± 18.4 to 201.4 ± 17.1 nm with negative surface charge. However, the yield obtained increased as the initiator was altered from KPS to V50, and when the acrylic acid molar ratio was increased from 1:1 to 1:3. In conclusion, changing the initiator and monomer molar ratio may affect the physicochemical properties of the nanocarriers and the %yield of the nanocarrier product. Further investigations are essential to obtain the favorable drug nanocarriers for drug delivery

Synthesis of Polyethylene Glycol Diacrylate/Acrylic Acid Nanoparticles as Nanocarriers for the Controlled Delivery of Doxorubicin to Colorectal Cancer Cells

Doxorubicin (Dox) is known for its potential to deliver desirable anticancer effects against various types of cancer including colorectal cancer. However, the adverse effects are serious. This study aimed to synthesize polyethylene glycol diacrylate (PEGDA)/acrylic acid (AA)-based nanoparticles (PEGDA/AA NPs) for Dox delivery to colorectal cancer cells. The NPs were synthesized using free-radical polymerization reaction using the monomers PEGDA and AA with their physical properties, drug loading and release, biocompatibility, and anticancer effect evaluated. The NPs were spherical with a size of around 230 nm, with a 48% Dox loading efficiency and with loading capacity of 150 µg/mg. Intriguingly, the NPs had the ability to prolong the release of Dox in vitro over 24 h and were non-toxic to intestinal epithelial cells. Dox-loaded PEGDA/AA NPs (Dox-NPs) were able to effectively kill the colorectal cancer cell line (HT-29) with the Dox-NPs accumulating inside the cell and killing the cell through the apoptosis pathway. Overall, the synthesized PEGDA/AA NPs exhibit considerable potential as a drug delivery carrier for colon cancer-directed, staged-release therapy

Development of Alginate/Chitosan Microparticles for Dust Mite Allergen

Purpose: To develop chitosan/alginate microparticles for the mucosal delivery of allergen from dust mite ( Dermatophagoides pteronyssinus ). Methods: Chitosan/alginate microparticles were prepared by ionotropic gelation. The effects of polymer content, crosslinking agent, and preparation method on the physicochemical characteristics of the microparticles as well as their in vitro cytotoxicity were investigated. Results: The microparticles were small (1 -17 µm) and spherical in shape. The highest allergen content (0.30 ± 0.07 mg/g) was obtained with 2.5 % initial allergen loading in chitosan-triphosphate (CS-TPP) microparticles. Sustained allergen release (approx. 50 % over 24 h) was observed from alginate-coated chitosan microparticles. Allergen incorporation method and initial drug-loading could be varied to obtain optimum particle size with high allergen-loading and sustained release. The cytotoxicity of various microparticle formulations did not differ significantly (p > 0.05 ), as cell viability values were close to 100 %. Conclusion: This study indicates that alginate and alginate-coated chitosan microparticles are safe and can be further developed for mucosal allergen delivery