Chitosan is obtained by deacetylation of chitin. Chitosan versatility is directly related to the polymer's characteristics depending on the deacetylation process. The aim of this research was to study the parameters influencing deacetylation and to elucidate their effect on acetylation degree (DA) and molecular weight (MW). The effect on chitosan DA was investigated using a fractional factorial design 2(7-3) with seven factors and two variation levels. The tested factors were: X1=number of successive baths, X2=reaction time, X3=temperature, X4=alkali reagent, X5=sodium borohydride, X6=the atmospheric conditions and X7=alkali concentration. A mathematical model was investigated corresponding to the following relation ŷ=7.469-1.344X1-1.094X2-3.094X3+1.906X4+0.656X5+0.906X6-1.031X7+0.469X1X2-0.781X3X4+0.906X1X3X4 with R2=0.99. This model allows fixing experimental conditions for each desired DA. To study the effect on chitosan MW, only atmospheric conditions and use of sodium borohydride as an oxygen scavenger were investigated. The use of sodium borohydride and nitrogen atmosphere was found to have a protective effect against chitosan degradation during deacetylation.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.ijbiomac.2014.06.051 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Nutritional evaluation after copper cloud point extraction in spirulina (Arthrospira sp.) samples with determination by digital image colorimetry.
Food Chem
December 2024
Universidade Estadual do Sudoeste da Bahia, Campus de Jequié, Departamento de Ciências e Tecnologias, Rua José Moreira Sobrinho s/n, 45208-091 Jequié, Bahia, Brazil; Universidade Federal da Bahia, Instituto de Química, Campus da Federação/Ondina, Rua Barão de Geremoabo s/n, 40.170-115, Salvador, Bahia, Brazil. Electronic address:
This study presents the development of a procedure based on copper preconcentration at the cloud point of commercial spirulina dietary supplements, with determination by digital image colorimetry. A fractional factorial design 2 and Doehlert matrix were applied in the method optimization. The developed method presented 0.
View Article and Find Full Text PDFEffect of Process Parameters on Nano-Microparticle Formation During Supercritical Antisolvent Process Using Mixed Solvent: Application for Enhanced Dissolution and Oral Bioavailability of Telmisartan Through Particle-Size Control Based on Experimental Design.
Pharmaceutics
November 2024
College of Pharmacy and Research Institute for Drug Development, Pusan National University, 63 Busandaehak-ro, Geumjeong-gu, Busan 46241, Republic of Korea.
This study investigates the impact of supercritical antisolvent (SAS) process parameters on the particle formation of telmisartan, a poorly water-soluble drug. A fractional factorial design was employed to examine the influence of the SAS process parameters, including solvent ratio, drug solution concentration, temperature, pressure, injection rate of drug solution, and CO₂ flow rate, on particle formation. Solid-state characterizations of the SAS process particles using XRD and FT-IR confirmed their amorphous nature.
View Article and Find Full Text PDFNaïve Bayes is an interpretable and predictive machine learning algorithm in predicting osteoporotic hip fracture in-hospital mortality compared to other machine learning algorithms.
PLOS Digit Health
January 2025
Department of Geriatric Medicine, The Canberra Hospital, ACT Health, Canberra, Australia.
Osteoporotic hip fractures (HFs) in the elderly are a pertinent issue in healthcare, particularly in developed countries such as Australia. Estimating prognosis following admission remains a key challenge. Current predictive tools require numerous patient input features including those unavailable early in admission.
View Article and Find Full Text PDFOptimizing extrusion processes and understanding conformational changes in itraconazole amorphous solid dispersions using in-line UV-Vis spectroscopy and QbD principles.
Int J Pharm X
December 2024
Leicester School of Pharmacy, De Montfort University, Leicester LE1 9BH, UK.
This paper presents a comprehensive investigation of the manufacturing of itraconazole (ITZ) amorphous solid dispersions (ASDs) with Kolllidon® VA64 (KVA64) using hot-melt extrusion (HME) and in-line process monitoring, employing a Quality by Design (QbD) approach. A sequential Design of Experiments (DoE) strategy was utilized to optimize the manufacturing process, with in-line UV-Vis spectroscopy providing real-time monitoring. The first DoE used a fractional factorial screening design to evaluate critical process parameters (CPPs), revealing that ITZ concentration had the most significant impact on the product quality attributes.
View Article and Find Full Text PDFAssessing multidimensional fidelity in a pilot optimization trial: A process evaluation of four intervention components supporting medication adherence in women with breast cancer.
Transl Behav Med
January 2025
Leeds Institute of Health Sciences, University of Leeds, Leeds LS2 9NL, UK.
Adherence to adjuvant endocrine therapy in women with breast cancer is low. We conducted a 24-1 fractional factorial pilot optimization trial to test four intervention components supporting medication adherence [text messages, information leaflet, acceptance and commitment therapy (ACT), self-management website], in the preparation phase of the multiphase optimization strategy. Guided by the National Institute of Health Behavior Change Consortium fidelity framework, we investigated fidelity of design, training, delivery, receipt, and enactment of four intervention components.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!