Microwave-Assisted Synthesis of Para-Nitrophenol Using Calcium Nitrate

Conventional process of nitrating phenolic compounds involves the use of excess corrosive reagents that impose environmental threats. Rapid and environmentally friendly microwave-assisted nitration of phenol has been employed to limit the use of corrosive nitric acid and sulfuric acid. In this study, phenol is reacted to calcium nitrate and acetic acid, which served as nitrating agents. The solution is irradiated under microwave to complete the nitration process. This microwave-assisted- synthesis is a rate- enhanced process that showed complete nitration in a short reaction time of 1 min with a high yield of 89%. Bands of phenyl ring, OH, CO, and nitro groups observed in the FTIR spectra correspond to the vibration modes of para-nitrophenol. GCMS analysis showed a retention time of 7 min for the product with 139m/z base peak with matches that confirms the synthesis of para- nitrophenol. This microwave-assisted method can be employed as an efficient, environmentally safe, and rapid alternative nitration method for the synthesis of para-nitrophenol.

Synthesis Of L-Menthyl Acetic by Esterification L-Menthol and Acetic Anhydride with Variation Of Time

l-menthyl acetic is an ester with specific aroma that synthesized by reaction of l-menthol and acetic anhydride and useful in fragrance industry. This paper reports influenced variation of time reaction toward ester product and characteristics l- menthyl acetic based on TLC, FTIR, GC and GC-MS. Reaction using l-menthol, acetic anhydride and catalyst H­2­SO­4­ 98 % in diethyl eter solvent at temperature 60 °C with variation of time reaction (45, 60, 75, 90, 105 minutes). The result of research is variation of time influence product with highest yield 88,43 % for 90 minutes. Monitoring TLC achived R­f­ = 0,82; analysis by FTIR achived specific wave number ester 1736,96 cm-1; analysis by GC achived t­r­ = 14,82 minutes and analysis by GC-MS achived t­r­ = 16,13 minutes with base peak m/z = 95.

Anterior femoral cut in total knee arthroplasty: a classification proposal

<p class="abstract"><strong>Background:</strong> The cut of the anterior femur (CAF) sets the rotation of the femoral component, which could affect patellar tracking, and influence the clinical results on total knee arthroplasty (TKA). The aim of this study was to suggest a classification for anterior femoral cut in TKA.</p><p class="abstract"><strong>Methods:</strong> Images of anterior femoral cuts were aggregated in different shapes and defined a classification. One-hundred femoral image’s cuts were analysed by 5 orthopaedic surgeons, which classified them twice. To analyse inter and intra-observer agreement, the Fleiss Kappa test was used.<strong></strong></p><p class="abstract"><strong>Results:</strong> The study proposes the following CAF classification, type 1 (one peak) and type 2 (two peaks); subtypes 1 (a) a central base peak, 1 (b) a lateral base peak, 2 (a) two peaks where the smallest is in the lower half, and 2 (b) two peaks where the smallest is in the upper half. In our study, type 2 (a) was the most common type (54.5%), followed by type 1 (b). The analysis showed good intra- and inter-observer agreements (mean K of 0.774 and 0.627, respectively). The intra and inter-observer concordance was statistically significant in all the analyses.</p><p class="abstract"><strong>Conclusions:</strong> The CAF classification system for TKA is considered a reproducible classification. To our knowledge, there is no study describing a shape’s classification of this cut. A slight rotation of the femoral cutting guide could change the axial rotation and positioning of the femoral component. An undesirable cut could lead to different patellofemoral offset and could consequently cause anterior pain and instability.</p>

MEKANISME REAKSI FRAGMENTASI SENYAWA KIMIA DALAM KULIT BUAH ALPUKAT (Persea americana Mill.)

ABSTRACTInvestigation of the fragment structure of ions and fragmentation reaction is crucial and needs to be done to reconstruct the chemical structure of the examined sample. Therefore, it is necessary to study the fragmentation mechanisms of chemical compound that identified from avocado peel to study the rules of the fragmentation reaction that occurs Sample analysis was examined using Gas Chromatography-Mass Spectrometry (GC-MS) with ionization Electron Impact (EI). Two compounds foun in avocado peel are 1,2,4-trihidroksiheptadek-12,16-diyne and 1,2,4-trihidroksiheptadek-16-yne-18-ene following the principle of even electron positive (EE+) which tends to always form even electron positive (EE+) and even electron neutral (EE0). The fragmentation mechanisms in both compounds are σ bond dissociation reaction and i cleavage which forms even electron positive (EE+) and even electron neutral (EE0). The fragmentation mechanism of the compounds in avocado peel can be estimated through interpretation of GC-MS mass spectra with base peak m/z 87. Keywords : Persea americana Mill.; GC-MS; fragmentation; 1,2,4-trihidroksiheptadek-12,16-diyne; 1,2,4-trihidroksiheptadek-16-yne-18-ene ABSTRAKPenyidikan struktur ion-ion fragment serta reaksi fragmentasinya sangat penting dan perlu dilakukan untuk dapat merekonstruksi kembali struktur kimia sampel yang diperiksa. Oleh karena itu, perlu diketahui mekanisme fragmentasi senyawa kimia yang diidentifikasi dari sampel kulit buah alpukat untuk mengetahui kaidah reaksi fragmentasi yang terjadi. Analisis sampel dilakukan menggunakan Gas-Chromatography-Mass Spectrometry (GC-MS) dengan cara ionisasi Electron Impact (EI). Dua senyawa yang terkandung dalam kulit buah alpukat yaitu senyawa 1,2,4-trihidroksiheptadek-12,16-diena dan senyawa 1,2,4-trihidroksiheptadek-16-ena-18-una mengikuti kaidah fragmentasi ion elektron genap positif (EE+) cenderung untuk selalu membentuk ion elektron genap positif (EE+) dan molekul elektron genap netral (EE0). Mekanisme fragmentasi pada kedua senyawa tersebut terjadi melalui reaksi dissosiasi ikatan σ dan reaksi pemutusan induktif membentuk ion elektron genap positif (EE+) dan molekul elektron genap netral (EE0). Mekanisme fragmentasi senyawa dalam kulit buah alpukat dapat diperkirakan melalui interpretasi spektrum massa GC-MS dengan base peak m/z 87. Kata kunci: Persea americana Mill.; GC-MS; fragmentasi; 1,2,4-trihidroksiheptadek-12,16-diena; 1,2,4-trihidroksiheptadek-16-ena-18-una

Preparation and evaluation of a stable and sustained release of lansoprazole-loaded poly(d,l-lactide-co-glycolide) polymeric nanoparticles

The aim of the study was to prepare lansoprazole (LNS)-loaded poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles in order to improve the physicochemical stability associated with LNS. We synthesized LNS-loaded PLGA nanoparticles in the presence of magnesium oxide as alkalizer to improve the release of LNS and stability against photodegradation. The LNS-encapsulated PLGA nanoparticles were developed by the nanoprecipitation/solvent evaporation method, resulting in a particle size of 246.7 ± 3.4 nm, polydispersity index (PDI) of 0.126, percent drug entrapment (PDE) of 82.85 ± 4.5%, percent drug loading (PDL) of 3.54 ± 0.34%, and pH of 8.10 ± 0.56. The developed nanoparticles were further evaluated for in vitro release and resistance to photodegradation by NMR spectroscopy and LC-MS. The sustained release of the drug was confirmed after the encapsulation of LNS in the PLGA matrix. The protection of LNS in the PLGA matrix against photodegradation was confirmed by NMR and LC-MS studies. The LC-MS of UV-exposed samples of pure LNS and LNS-loaded PLGA nanoparticles at 254 nm showed the same (M + 1) peak at 370 m/e, and the base peak at 369 m/e accounted for the unchanged structure of LNS inside PLGA nanoparticles. Overall, it was proved that PLGA nanoparticles in the presence of magnesium oxide are an efficient carrier to deliver and protect LNS from physicochemical instability.

ANALISIS FRAGMENTASI GC-MS SENYAWA AKTIF ANTIKANKER LEUKEMIA FRAKSI KLOROFORM UMBI BAWANG TIWAI (Eleutherine bulbosa (Mill.) Urb)

Tiwai Onion (Eleutherine bulbosa (Mill.) Urb.) is an Iridaceae tribe which is a typical plant of Borneo. Its used by the Dayak community, among others, for colon cancer, breast cancer, diabetes mellitus, hypertension, lowering cholesterol, strokes, boils, anti-bleeding and abdominal pain. The purpose of this study was to determine the components of anticancer compounds of chloroform fraction by GC-MS method. The results of GC-MS spectrum analysis based on the base peak equation of the chloroform fraction contain 9,12-Octadecadienoic Acid, and 1- (2,3,5,6-Tetramethyl phenyl) Ethanone which has the potential as an anticancer.

ISOLATION AND IDENTIFICATION OF SECONDARY METABOLIT COMPOUNDS IN ETIL ASETIC FRACTIONS ON MINDI LEAF

This study was aimed at isolating and identifying secondary metabolites contained in the ethyl acetate fraction of parasitic leaves (Dendrophthoe falcata (L.f)) Ettingsh which attaches to the stem of Mindi plants (Melia azedarach). The subjects in this study were leaves of parasitic plants on Mindi plants. While the objects in this study were secondary metabolites from the ethyl acetate fraction of the leaves of parasite plants attached to the mindi plant. The research method was carried out by extracting macerated leaves of D. falcata with ethanol solvents. The ethanol extract obtained was partitioned using n-hexane, chloroform, and ethyl acetate. Ethyl acetate fraction was separated by gravity column chromatography (CCG). The relatively non-polar fraction that has shown a single stain is tested for purity using 3 different types of solvents and identified using UV-Vis, IR, and GC-MS. The results showed that the compounds that could be isolated and identified from the relatively non-polar ethyl acetate fraction of D. falcata leaves were stigmast-5-en-3β-ol with an abundance of 6.49%, having a molecular weight of m / z 414 with base peak 55. Compounds sterols are compounds commonly found in parasitic plantsISOLASI DAN IDENTIFIKASI SENYAWA METABOLIT SEKUNDER PADA FRAKSI ETIL ASETAT DAUN MINDIPenelitian ini bertujuan untuk mengisolasi dan mengidentifikasi senyawa metabolit sekunder yang terdapat dalam fraksi etil asetat daun benalu (Dendrophthoe falcata (L.f)) Ettingsh yang menempel pada batang tumbuhan Mindi (Melia azedarach). Subjek dalam penelitian ini adalah daun tumbuhan benalu pada tanaman mindi. Sedangkan objek dalam penelitian ini adalah senyawa metabolit sekunder dari fraksi etil asetat daun tumbuhan benalu yang menempel pada tanaman mindi. Metode penelitian dilakukan dengan ekstraksi maserasi daun D. falcata dengan pelarut etanol. Ekstrak etanol yang diperoleh dipartisi menggunakan n-heksana, kloroform, dan etil asetat. Fraksi etil asetat dipisahkan secara kromatografi kolom gravitasi (KKG). Fraksi relatif non polar yang sudah menunjukkan noda tunggal diuji kemurniannya menggunakan 3 jenis pelarut yang berbeda dan diidentifikasi menggunakan UV-Vis, IR, dan GC-MS. Hasil penelitian menunjukkan senyawa yang dapat diisolasi dan diidentifikasi dari fraksi etil asetat relatif nonpolar daun D. falcata adalah stigmast-5-en-3β-ol dengan kelimpahan 6,49 %, memiliki berat molekul m/z 414 dengan base peak 55. Senyawa sterol merupakan senyawa yag lazim ditemukan dalam tumbuhan benalu.