Publications by authors named "Tu Lee"

The surprisingly stable irinotecan hydrochloride trihydrate injection concentrate having a supersaturated concentration of 20 mg/mL at 25 °C was due to the frustration of 150-nm sized liquid-like nanosized clusters formed by the aggregation of dimers of 1.5 nm in an aqueous phase, evidenced by the non-linearity of van't Hoff plot and dynamic light scattering measurement. The adoption of this stable supersaturated solution at 20 mg/mL by manufacturers as the commercial concentration was beneficial due to the less volume being involved throughout the manufacturing, handling, storage and transportation of the commercial product, while also enabling a versatile on-site concentration adjustment by dilution prior to intravenous administration.

View Article and Find Full Text PDF
Article Synopsis
  • Deployable tubular structures can transform from compact to functional forms and are useful in various engineering applications.
  • These structures face challenges in balancing flexibility and stiffness, but using compliant materials helps enhance their adaptability, albeit often at the cost of strength under pressure.
  • The proposed solution utilizes origami-inspired techniques and a self-locking mechanism to improve performance, resulting in structures that can adapt their properties for different scenarios, paving the way for advancements in deployment technology.
View Article and Find Full Text PDF
Article Synopsis
  • The study highlights the need for an environmentally friendly, organic solvent-free method of producing pharmaceutical salts, specifically using a salt of cinnarizine (CNZ) and malic acid through twin screw extrusion (TSE) with water.
  • Initial grinding experiments indicated that malic acid could effectively form a salt with CNZ, confirmed by microscopy and pH-solubility analysis showing successful crystallization.
  • The research demonstrates that TSE can produce salt crystals with properties similar to those obtained using conventional solvent methods, supporting its potential as a sustainable manufacturing approach in the pharmaceutical industry.
View Article and Find Full Text PDF

This study describes the preparation, characterization, and influence of the enantiopure vs. racemic coformer on the physico-chemical properties of a pharmaceutical cocrystal. For that purpose, two new 1:1 cocrystals, namely lidocaine:dl-menthol and lidocaine:d-menthol, were prepared.

View Article and Find Full Text PDF
Article Synopsis
  • Goldberg polyhedra are notable for their unique patterns and have practical applications, but their geometry is not well understood.
  • This study introduces a new method to systematically determine the topology and control the geometry of Goldberg polyhedra by optimizing the shapes of structures known as cages.
  • The researchers successfully created nearly spherical Goldberg polyhedra with precise vertex positioning, providing strong evidence for this new type, and implemented optimizations to minimize edge length variations for reduced costs in engineering projects.
View Article and Find Full Text PDF

Form II paracetamol has captured the interest of researchers due to its improved compressibility. However, its low stability has made it difficult to be produced on a large scale with good reproducibility. In the present study, the selective polymorphic formation of paracetamol was carried out by cooling crystallization with four types of additives: adipic acid, fumaric acid, oxalic acid, and succinic acid.

View Article and Find Full Text PDF

A novel hydrate form of sodium dodecyl sulfate (SDS) was firstly discovered through a hydrate screening with the use of organic solvents, while SDS is generally prepared solely in aqueous media. Surprisingly, a novel SDS hydrate form with needle-shaped crystals produced by adding acetonitrile to a 20 wt % SDS aqueous solution at a ratio of 3:1 (v/v) and further cooling to around 5 °C could be found with a trace amount in one of the two purchased SDS products that we examined. After comprehensive solid-state characterizations by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR), Raman spectroscopy, dynamic vapor sorption (DVS), and elemental analysis (EA), it is also successfully made directly from the synthesis of SDS through esterification and saponification.

View Article and Find Full Text PDF
Article Synopsis
  • The COVID-19 pandemic has significantly increased the global need for personal protective equipment (PPE), particularly face shields for healthcare workers.
  • Existing face shield designs may not meet the high demand, especially in Low and Middle-Income countries.
  • This paper introduces a cost-effective origami technique to create face shields from flat plastic sheets, adaptable to various manufacturing methods and allowing for quick customization to fit different needs.
View Article and Find Full Text PDF

The concept of drug recycle by recovering active pharmaceutical ingredients (APIs) from unused tablets and capsules was demonstrated using acetaminophen, tetracycline HCl, and (,)-(±)-ibuprofen as case examples. The recovery process comprised three core unit operations: solid-liquid extraction, filtration, and crystallization. Recovery yields of 58.

View Article and Find Full Text PDF

Sodium dodecyl sulfate (SDS)·1/8 hydrate (NaCHSO·1/8HO) crystals were successfully produced by evaporation, antisolvent addition, cooling crystallization, and isothermal aging in a common stirred tank. A clear 33.3 wt % SDS aqueous solution was concentrated by evaporation to a 60 wt % coagel consisting of numerous SDS hydrates and water.

View Article and Find Full Text PDF

Salts are generally prepared by acid-base reaction in relatively large volumes of organic solvents, followed by crystallization. In this study, the potential for preparing a pharmaceutical salt between haloperidol and maleic acid by a novel solvent-free method using a twin-screw melt extruder was investigated. The pH-solubility relationship between haloperidol and maleic acid in aqueous medium was first determined, which demonstrated that 1:1 salt formation between them was feasible (pH 4.

View Article and Find Full Text PDF

The adsorption of phenylaniline (Phe) enantiomers on (+)-polyaniline (PAN)-chelated [In(OH)(bdc)]n microcrystals was carefully designed and studied by using the Job titration, circular dichroism, X-ray photoelectron spectroscopy, and photoluminescence to mimic heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors in selective, but not specific, ligand binding with chiral recognition and signal transduction. Six essential working principles across different length scales are unraveled: 1) a chiral (+)-PAN (host), 2) specific sites for Phe-(+)/PAN (guest-host) binding, 3) a conformational change of (+)-PAN after binding with Phe enantiomers, 4) different degrees of packing for (+)-PAN, 5) interactions between (+)-PAN and the underlying signal-generating framework (i.e.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates the impact of different baffle types and tank sizes on the spherical agglomeration process for dimethyl fumarate, revealing significant variations in particle size distribution.
  • Despite differing particle sizes, properties like dissolution profiles and flowability remained consistent among agglomerates from the same size cut after sieving.
  • The study emphasizes that while mechanical properties and density may decline with baffle changes and scaling, longer maturation times can enhance the density and strength of the agglomerates, allowing for controlled size distribution through careful sieving and blending.
View Article and Find Full Text PDF

This study reports the prevalence of duck hepatitis A virus (DHAV) types 1 and 3 on Korean duck farms. By RT-nested PCR assays specific for DHAV-1 or DHAV-3, DHAV-1 was detected in 9 of 157 liver samples (5.7 %) from 2 of 30 farms (6.

View Article and Find Full Text PDF
Article Synopsis
  • Wastewater treatment plants in South Korea struggle with low total phosphorus (TP) removal efficiency during summer due to high temperatures and fluctuating inflow from rainfall.
  • The study aims to improve TP removal by injecting fixed external carbon sources, specifically acetate and propionate, to enhance the dominance of polyphosphate accumulating organisms (PAOs) over glycogen accumulating organisms (GAOs).
  • Results showed that adding these external sources increased TP removal efficiency and maintained stability under temperature variations, with the optimal carbon source ratio identified as 2:1 acetate to propionate.
View Article and Find Full Text PDF

This study fabricates the optically active uniform SiGe/Si multiple quantum well (MQW) nanorod and nanodot arrays from the Si0.4Ge0.6/Si MQWs using nanosphere lithography (NSL) combined with the reactive ion etching (RIE) process.

View Article and Find Full Text PDF
Article Synopsis
  • The experimental procedures serve as a screening tool to explore molecular interactions between chiral molecules and solvents, particularly focusing on aspartic acid.
  • A minimal concentration of 1% l-aspartic acid is sufficient to convert a racemic compound into a racemic conglomerate, enhancing the likelihood of establishing biochirality.
  • Traditional crystallization methods alone were inadequate for enantioseparation, necessitating the application of nonclassical crystallization theory to explain the dynamics of different aspartic acid solutions.
View Article and Find Full Text PDF

Culicoides biting midges were collected on three cattle farms weekly using light traps overnight from May to October between 2010 and 2011 in the southern part of Korea. The seasonal and geographical abundance of Culicodes spp. were measured.

View Article and Find Full Text PDF

The taste sensing capabilities of a "biomimetic tongue" based on the photoluminescence (PL) responses of metal-organic frameworks (MOFs), [In(OH)(bdc)]n (bdc=1,4-benzenedicarboxylate), [Tb(btc)]n (MOF-76, btc=benzene-1,3,5-tricarboxylate), and [Ca3(btc)2(DMF)2(H2O)2]·3H2O are proven on aqueous solutions of five basic tastants: sucrose (sweet), caffeine (bitter), citric acid (sour), sodium chloride (salty) and monosodium glutamate (umami). For [In(OH)(bdc)]n, the tastant interacts stereochemically with poly(acrylic acid) (PAA) and alters its conformations. The frequency and magnitude of chelation between COO(-) pendant groups of PAA and In(3+) nodes of [In(OH)(bdc)]n framework influence the corresponding PL reponses.

View Article and Find Full Text PDF

After the initial discovery of antiproliferative and apoptosis-inducing properties of a camptothecin-inspired pentacycle based on a 1H-indeno[2',1':5,6]dihydropyrido[2,3-d]pyrimidine scaffold, a library of its analogues as well as their oxidized planar counterparts were prepared utilizing a practical multicomponent synthetic protocol. The synthesized compounds exhibited submicromolar to low micromolar antiproliferative potencies toward a panel of human cancer cell lines. Biochemical experiments are consistent with the dihydropyridine library members undergoing intracellular oxidation to the corresponding planar pyridines, which then inhibit topoisomerase II activity, leading to inhibition of proliferation and cell death.

View Article and Find Full Text PDF

The aim of this paper is to design initial salt screening procedures for manufacturing ibuprofen. Salt forms of a pharmaceutical acid racemic (R,S)-(+/-)-ibuprofen and their "developable" synthetic routes were ferreted out simultaneously through the screening of seven bases of sodium hydroxide, potassium hydroxide, L-arginine, L-histidine, L-lysine, diethanolamine, and tris(hydroxymethyl)aminomethane (THAM), and the match with the use of nine organic solvents of methanol, dimethyl sulfoxide, ethanol, N, N-dimethylformamide, acetonitrile, isopropyl alcohol, 1,4-dioxane, acetone, and tetrahydrofuran mainly in the presence of water in 20 mL scintillation vials. Racemic (R,S)-(+/-)-sodium ibuprofen dihydrate, a well-known ibuprofen salt and the newly discovered racemic (R,S)-(+/-)-THAM ibuprofen, appeared as white-squared powders with a molecular weight of 327.

View Article and Find Full Text PDF

The purpose of this article is to promote two simple and scalable methods to accelerate the formulation development of formulated granules using acetaminophen as a model system. In method I, formulated granules made from the batch of small particle-sized acetaminophen (1) by ball milling the batch of large particle-sized acetaminophen (2), and the mixture of the two batches at equal weights (mix) gave the dissolution rate constants (k) of k(1) = 0.43 +/- 0.

View Article and Find Full Text PDF

Purpose: The aim of this paper is to enhance the dissolution rate of racemic (R,S)-(+/-)-sodium ibuprofen dihydrate via a bio-inspired method of growing mesocrystals.

Materials And Methods: Mesocrystals of racemic (R,S)-(+/-)-sodium ibuprofen dihydrate were successfully prepared from a supersaturated aqueous solution of racemic (R,S)-(+/-)-sodium ibuprofen dihydrate having the initial degree of supersaturation, S ( 0 ), of 1.326 and the initial saturated concentration, C*, of 0.

View Article and Find Full Text PDF