The effect of ball-milling upon certain properties of proteins

Monder, Carl; Ramstad, P.E.

doi:10.1016/0003-9861(53)90209-4

Cited by 7 publications

(4 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[73] However, this procedure is known to affect structural and chemical properties of keratins, increasing the number of free sulfhydryl groups. [74] Because our specific goal was to study intact chemical speciation of arsenic, we tried to preserve the structural properties of the nail tissues and confined our studies to less damaged, dissected or whole clippings as described in the 'Methodology' part of the paper.…”

Section: Resultsmentioning

confidence: 99%

Synchrotron X-ray absorption spectroscopy analysis of arsenic chemical speciation in human nail clippings

et al. 2014

View full text Add to dashboard Cite

Environmental context. Chronic ingestion of arsenic leads to its accumulation in keratinous tissues, which can represent a risk factor for developing cancer. We use synchrotron X-ray absorption spectroscopy to investigate chemical bonding of arsenic in the keratins from nail clippings of volunteers from areas in Atlantic Canada with low-to-moderate arsenic contamination of drinking water. The study helps our understanding of arsenic metabolism and its role in cancer development.Abstract. Drinking water aquifers in many areas of the world have naturally elevated levels of inorganic arsenic exceeding the World Health Organization limit. Arsenic concentrations in human nail clippings are commonly used as a biomarker of exposure to this toxic element. However, the chemical form of arsenic accumulated in nail tissues is not well determined. We employed synchrotron microprobe and bulk X-ray absorption spectroscopy techniques to analyse the concentration and chemical speciation of arsenic in the finger-and toenail clippings of volunteers living in the vicinity of Sackville, New Brunswick, Canada. This area is known to have low-to-moderately elevated levels of arsenic in ground water. Arsenic species in clippings were represented by three main groups, distinguished by the As-K near-edge X-ray absorption fine structure spectra: (1) As III type, which can be fitted as a mixture of As bound to thiols, and also to oxygen or methyl groups, with a small contribution from As V species, (2) As V type, best represented by fitting arsenate in aqueous solution and (3) The As III þ As V mixture type. The high proportion (%) of sulfur-bound arsenic species most likely corresponds to binding between arsenic (in its trivalent and, to a lesser extent, pentavalent forms) and cysteine residues in the sulfur-rich fraction of keratin and keratin-associated proteins. Further work is needed to explore whether these chemical species could be used as toxicity biomarkers of human exposure to elevated levels of As in drinking water.

show abstract

Section: Resultsmentioning

confidence: 99%

Synchrotron X-ray absorption spectroscopy analysis of arsenic chemical speciation in human nail clippings

et al. 2014

View full text Add to dashboard Cite

show abstract

“…of a standard, freshly prepared solution of glutathione in formamide (the concentration being about 10 mg./ 100 ml. ) , 10.0 ml. of a solution of the color reagent was added.…”

Section: Standardization Of the Color Reagentmentioning

confidence: 99%

“…/3-lactoglobulin was also used as a test compound. To a sample of 2 to 3 mg. of j3-lactoglobulin of known moisture content, 10.0 ml. of a formamide solution of the color reagent was added.…”

Section: Standardization Of the Color Reagentmentioning

confidence: 99%

The Estimation of Sulfhydryl Groups in Wool by Means of 1-(4-Chloromercuriphenylazo)- Naphthol-2

Burley

1956

Textile Research Journal

View full text Add to dashboard Cite

IT has recently been reported [4] that sulfhydryl groups in wool fibers may be detected and estimated by means of a formamide solution of Bennett's color reagent, 1-(4-chloromercuriphenylazo ) -naphthol-2 [ 1,15,16] . Further experiments have now shown that the acidity and water content of the formamide are important in determining the rate and extent of penetration of this reagent into the fiber, and that the values reported earlier are therefore too low. This communication gives directions for increasing the reliability of the method for use on intact fibers and describes the standardization of the reagent on known sulfhydryl compounds. A subsequent communication will describe how the method can be shortened by using supercontracted and pulverized wool. A brief outline of the methods, without experimental details, has already been given [5]. Materials WoolThe wool samples used, which unless otherwise stated, were from the root ends of one good quality South African merino fleece (from sheep B51.3), were purified by Soxhlet-extraction for 24 hr. with hexane, then for 12 hr. with ethyl alcohol, followed by soaking for 24 hr. in frequently changed distilled water.

show abstract

“…Lastly, ball milling is a process where powders are ground between one or more typically metal balls in a grinding bowl. This process has been widely used in the food industry to reduce protein powders prior to processing (Monder and Ramstad, 1953; Roa et al, 2014). …”

Section: Introductionmentioning

confidence: 99%

Milling solid proteins to enhance activity after melt-encapsulation

Lee

Maia

Pokorski

2017

International Journal of Pharmaceutics

View full text Add to dashboard Cite

Polymeric systems for the immobilization and delivery of proteins have been extensively used for therapeutic and catalytic applications. While most devices have been created via solution based methods, hot melt extrusion (HME) has emerged as an alternative due to the high encapsulation efficiencies and solvent-free nature of the process. HME requires high temperatures and mechanical stresses that can result in protein aggregation and denaturation, but additives and chemical modifications have been explored to mitigate these effects. This study explores the use of solid-state ball milling to decrease protein particle size before encapsulation within poly (lactic-co-glycolic acid) (PLGA) via HME. The impact of milling on particle dispersion, retained enzymatic activity, secondary structure stability, and release was explored for lysozyme, glucose oxidase, and the virus-like particle derived from Qβ to fully understand the impact of milling on protein systems with different sizes and complexities. The results of this study describe the utility of milling to further increase the stability of protein/polymer systems prepared via HME.

show abstract

The effect of ball-milling upon certain properties of proteins

Cited by 7 publications

References 18 publications

Synchrotron X-ray absorption spectroscopy analysis of arsenic chemical speciation in human nail clippings

Synchrotron X-ray absorption spectroscopy analysis of arsenic chemical speciation in human nail clippings

The Estimation of Sulfhydryl Groups in Wool by Means of 1-(4-Chloromercuriphenylazo)- Naphthol-2

Milling solid proteins to enhance activity after melt-encapsulation

Contact Info

Product

Resources

About