Functional Group Assignments Research Articles

Chitosan/PVA Nanocomposite Films with Improved Structural, Vibrational and Optical Properties

Herein, the solvent costing method was used to prepare the chitosan/poly vinyl alcohol (CS/PVA) nanocomposite films and the properties of structural, vibrational, optical, thermal and electrochemical of these films have been reported. XRD and SEM were confirmed the presence of CS in PVA matrix. The vibrational properties and functional group assignment were studied. The thermal stability and electrochemical properties of chitosan/poly vinyl alcohol nanocomposite films were reported.

Investigations on growth, XRD, strain, FTIR, UV–Vis NIR, photoluminescence, SHG, and Z-scan analyses of L-cysteine picrate single crystal for NLO and optical limiting applications

Organic single crystal of L-cysteine picrate (LCP), an efficient NLO material for frequency conversion, optoelectronic, and optical limiting applications has been grown within 20 days by Slow Evaporation Solution Technique (SEST). PXRD analysis shows that the LCP is subjected to the noncentrosymmetric space group of P21 with a monoclinic crystal system. The very low strain value depicts that the level and dislocations of the defect in the lattice of LCP crystal are very low. The various functional group assignments were investigated by using Fourier-Transform Infrared (FTIR) spectrum analysis with the range of 4000–400 cm−1. The optical analysis (UV–Visible) confirmed that the crystal has a lower cut-off wavelength of 250 nm and very low absorption in the entire visible region. Photoluminescence (PL) spectrum analysis confirmed that the material exhibits blue emission and is suitable for LED device fabrication. The SHG efficiency for LCP crystal is established to be 1.7 times higher than KDP material. Z-scan measurement determined the LCP exhibits two-photon absorption-induced optical limiting action with a nonlinear absorption coefficient of 0.70 × 10−10 m/W and onset limiting threshold of 2.36 × 1012 W/m2 which indicates that it can be used in making laser protection gadgets.

Growth, characterization and chemical computations of guanidinium trichloroacetate (GTCA) single crystal – DFT approach

ABSTRACT. Nonlinear optical (NLO) active guanidinium trichloroacetate (GTCA) crystal was synthesised and grown by using slow evaporation solution growth technique from mixed solvent. The grown crystal was characterized by single crystal X-ray diffraction (SXRD) and powder X-ray diffraction (PXRD) analysis. Fourier transform infrared (FTIR) spectrum of GTCA was recorded and the frequency assignments of various functional groups were compared with theoretical values. Mechanical strength of the grown crystal was studied using Vickers micro hardness tester. Thermal stability was studied using TG/DTA analyser. UV-Vis-NIR spectrum was recorded and the band gap energy was calculated. Geometry optimizations, first order hyperpolarizability, HOMO-LUMO energy gap, global reactive constants, thermodynamic properties, molecular electrostatic potential (MESP) and charge population were computed using B3LYP/6-31 G(d,p) basis set and DFT method and analysed.
 
 KEY WORDS: PXRD, FTIR, TG-DTA, DFT, NBO, Charge population
 
 Bull. Chem. Soc. Ethiop. 2023, 37(4), 1033-1045. 
 DOI: https://dx.doi.org/10.4314/bcse.v37i4.18

Thermodynamic and spectroscopic investigations of Shewanella putrefaciens CN32 cell envelope

A quantitative understanding of prokaryotic cell envelope reactivity is necessary to accurately describe the surface complexation reactions known to impact metal transport in the subsurface. The gram-negative bacterium Shewanella putrefaciens CN32 (CN32) has been the focus of previous cell envelope studies in large part due to its ability to directly influence iron and uranium geochemistry; however, important gaps remain in our understanding of reactions occurring on its cell envelope. Combining surface complexation modeling of potentiometric titration data with isothermal titration calorimetry provides an additional method to evaluate how well surface complexation models (SCMs) represent cell envelope reactivity. It also gives us the ability to determine site-specific enthalpies and entropies of protonation, which can aid both in site structure identification and description of conformational changes to those sites, further improving our understanding of the CN32 cell envelope. We gathered potentiometric and isothermal calorimetric titration data of CN32 over a range of ionic strength (0.02 – 0.53 M) while monitoring cell viability and performing Fourier transform infrared spectroscopy (FTIR) investigations. FTIR analysis was performed over a range of pH (4 – 9.4) to confirm identification of proton-active sites. Surface complexation modeling revealed that models involving 3 and 4 sites could adequately describe the potentiometric titration data; however, a 3-site model best represented the calorimetric data. We inferred the following site identities based on characteristic enthalpies, entropies, and equilibrium constants of protonation: carboxyl (log(K): 4.79 – 4.95), phosphoryl (6.69 – 6.97), and amine groups (9.37 – 9.64). Spectral corroboration via FTIR indicated the presence of chemical moieties consistent with these functional group assignments. Ionic strength was shown to have a significant impact on the concentration of all three sites at 95% confidence. Entropies and equilibrium constants of protonation for carboxyl and phosphoryl sites did not significantly change with ionic strength. For the carboxyl group, enthalpies of protonation varied significantly between the lowest and highest ionic strengths examined, though enthalpies at intermediate concentrations were not distinguishable. Enthalpies of protonation for the amine group were statistically different at each ionic strength. Additionally, entropies and equilibrium constants of protonation for the amine group were significantly affected by all ionic strengths tested. The entropy of protonation for the amine site changed from −21.5 ± 6.1 to +109.0 ± 4.2 J/molK−1 as ionic strength increased from 0.02 to 0.53 M, respectively. A change in the entropy of protonation of this magnitude and sign is indicative of a substantial conformational change in this functional group. Cell viability was significantly impacted over the course the titrations; however, viability did not impact SCMs results. In sum, these data fill gaps in our understanding of CN32 and provide new insights into the intricacies of its cell envelope.

Porphyrin aluminum MOF with ultra-high water sorption capacity: In-situ time-dependent ATR-FTIR spectroscopy and gravimetry to study mechanism of water bonding and desorption

Porphyrin-based aluminum metal-organic framework Al-MOF-TCPPH2 compound 1 is synthesized and activated to obtain compound 2. Its purity is demonstrated by ATR-FTIR spectroscopy, and spectral assignments of specific functional groups within the TCPP linker are provided as potential binding sites for adsorbate. Compound 2 reversibly sorbs and desorbs the significant amount of water (up to 50 wt. %) from humidified air and it forms the hydrated compound 3. Compound 3 contains as many as up to 25 water molecules bonded to several distinct groups in structural unit of Al-MOF-TCPPH2. In compound 3 water exists as small ice-like nanoclusters, in which water molecules are three-coordinated to other water molecules and the fourth bond is coordination of the surface water molecules d-H via their H atoms to functional groups in Al-MOF-TCPPH2. Further, water is bonded to the framework via the NH group, the carboxylate anion −COO−, phenyl group of the linker and the μ−OH group. Compound 3 facilely loses most of its water to air at moderate ambient relative humidity 45 %. During water loss, small ice-like nanoclusters with d-H waters are progressively transformed to those with four-coordinated waters denoted s-4. Chemical kinetics of water loss (desorption) by compound 3 has been investigated by in-situ time-dependent gravimetric method under ambient conditions. Kinetics of reaction of water desorption follows the pseudo-first order rate law with rate constant. The in-situ time-dependent ATR-FTIR spectroscopy demonstrates the capability to facilely identify multiple sorption sites of adsorbate to the MOF. Moreover, the combination of in-situ time-dependent ATR-FTIR spectroscopy and gravimetry forms a new unique experimental approach with significant potential. This approach can be facilely and successfully utilized in studies of mechanisms of reactions of sorption and desorption, determination of stoichiometry of complexes of sorbents with adsorbate, and studies of chemical kinetics of various solid-gas reactions under ambient and controlled environments.

Detailed Study of Three Halogenated Benzylpyrazole Acetamide Compounds with Potential Anticancer Properties

Spectroscopic and chemical properties of three acetamide derivatives are investigated experimentally and theoretically. Detailed functional group assignment shows that the important functional mode frequencies are in agreement with the simulated values. The nitrogen atom in the acetamide group has very strong hyper conjugative interactions with the neighboring groups. Studies of frontier orbitals showed that the LUMO is delocalized in mono substituted phenyl rings of all systems while the HOMO is over the pyrazole ring and acetamide group with changes in polarity. Electron localization function showed that electrons are more localized in the C–H bond adjacent to C–Cl bonds in the aromatic ring. Average local ionization energy in the molecule surface has also been reported. The compounds might exhibit inhibitory activity against antitumor protein-chromophore complexes.

Experimental and theoretical studies on bis (6-nitroquinoline) fumaric acid co-crystal

6-Nitroquinoline fumaric acid (C11H8N2O4), an organic co-crystal is grown using slow evaporation solution growth technique. The grown crystal is characterized by single crystal X-ray diffraction (SCXRD) and the title compound is crystallized in monoclinic crystal system with P21/n centrosymmetric space group. The OH···N and CH···O hydrogen bonds influence heterodimer formation in the crystal structure. The optical absorption spectrum of the title compound shows an absorption peak at 333 nm which contributes to π→π* transition. The transmission spectrum shows about 82% transparency in the visible region with lower cutoff wavelength 370 nm. The vibrational modes and assignments of functional groups are done using FTIR and Raman spectroscopic analyses. The CO stretching is the most characteristic vibration of the carboxylic acid group and it typically appears at 1393 cm−1. The thermal behavior of the present compound is evaluated by TG/DSC techniques and the melting point of the title crystal is 191 °C. The finger print plots show that H···O (41.9%) interactions are dominated interactions. These interactions are responsible for CH···O hydrogen bonds which play vital role in the structure stabilization. The first order hyperpolarizability value is calculated using B3LYP method with the extended 6–311++G(d,p) basis set and it is found as 4.5 times larger than that of urea.

Phytopharmacognostic Evaluation and Fourier Transform Infrared Fingerprint in the Quality Control of Various Culinary Herbs: AN ULTIMATE REMEDY IN ASIA

Background: The quality and efficacy of culinary herbs commonly practiced in Asia as a remedy for seasonal illnesses such as cold, flu, congestion, fever and inflammation, etc. The extemporaneous preparations of these culinary herbs are being formulated as traditional practice either in the form of extract, decoction, and paste etc. These culinary herbs are being practiced for curing sporadic illnesses since ancient time.
 Objectives: In present study five herbs’ i.e. Elettaria cardamomum (cardamom), Cinnamomum zeylanicum (cinnamon), Carum carvi (caraway), Oreganum vulgare (oregano) and Syzygium aromaticum (clove) have been obtained from the market to assure quality of herbs in local market.
 Methodology: Various quality control tests including microscopic evaluation, physico-chemical characteristics, Thin layer chromatography (TLC) and Fourier Transform Infrared spectroscopy (FTIR) have been performed to determine their compliance with the standards. The TLC has been used for the identification of the active ingredients on comparison of their Rf values with the reference standard. FTIR Spectra of these materials have been obtained to identify and confirm structural information and assignment of functional groups.
 Results: Many of the herbal samples used in this study have been complied with the available official standards as given in Pharmacopoeia. If the samples did not comply with the standards then it indicates that the sample belongs to spurious quality of raw herb, which is the prime cause that may interfere with the therapeutic efficacy and variability of outcomes.
 Conclusion: This study help to provide a significant data to herbal drug manufacturers for authentication of commercially available herbs which may be used in the formulation of extemporaneous or commercially available herbal medicine.

Preparation and characterization of Fe doped n-hydroxyapatite for biomedical application

Natural and synthetic biomaterials are often used in clinical utilization to assist, strengthen and to restore impaired tissue or biological functions. Iron doped bioactive nano-crystalline hydroxyapatite (Fe doped n-HAp) powder with different concentrations of Fe was successfully synthesized by the reflux method. The crystallinity of the samples was confirmed by powder XRD analysis and in 0.2 M Fe doping, the smallest crystalline size of 3.2 nm was obtained. SEM results indicate that higher concentration of Fe content has a considerable impact on the morphology of n-HAp material. The functional group assignments and the iron dopant incorporation has been analyzed and confirmed through FTIR and Raman results. The antibacterial activity test of Fe doped n-HAp mixed with amoxicillin antibiotic displays good inhibition to the bacterial strains.

Comparison of Average Inhibition Zones of Methanolic Extracts of Chaetomium globosum on the Growth of Different Groups of Pathogenic Micro-Organisms

The objectives of this study were analysis of the secondary metabolite products and evaluation of antibacterial activity. The FTIR analysis of Chaetomium globosum proved the presence of functional groupassignment Alkyl halides, Amide, and Alkane with Peak (Wave number cm-?) 1018.41 (Strong), 1238.30(Strong), 1317.38 (Strong), 1379.10 (Strong), 1614.42 (Bending), 2850.79 (Strong), 2920.23 (Strong). Zoneof inhibition (mm) of test bacterial strains to Chaetomium globosum bioactive compounds and standardantibiotics were (4.00±0.31), (4.77±0.13), (5.00±0.16), (3.22±0.41), and (4.29±0.11) uses Chaetomiumglobosum bioactive compounds, and (2.01±0.10), (1.77±0.41), (1.98±0.11), (2.00±0.30), and (1.05±0.42)uses Rifambin, and (2.42±0.18), (2.12±0.46), (1.40±0.12), (1.00±0.10), and (2.90±0.47) uses Kanamycinfor Staphylococcus aureus, Escherichia coli, Proteus mirabilis, Klebsiella pneumonia, Pseudomonaseurogenosa respectively. Chaetomium globosum was very highly active against Escherichia coli (4.77±0.13).

Spectral analysis and detailed quantum mechanical investigation of some acetanilide analogues and their self-assemblies with graphene and fullerene.

Spectroscopic analysis and different quantum mechanical studies of four pharmaceutically active compounds phenacetin, p-acetanisidide, 4'-butoxyacetanilide, and 4'-(3-chloropropoxy)acetanilide are reported in this manuscript. Simulated IR spectrum of these compounds was compared with experimentally available data, and essential functional group assignments were made. We also report the frontier orbital properties and other derived local energy descriptors which talks about the relative stability and reactivity. Photovoltaic efficiency of the compounds was studied from the simulated electronic spectra. The compound was found to interact with graphene and fullerene, to form molecular self-assembly. These self-assemblies showed tremendous enhancement in various physicochemical properties when compared with its constituents. The nature of the interactions between studied chemical species was discussed with the help of chemical reactivity principles. Biological activity of the compounds was predicted using molecular docking studies. It is interesting to see that on adsorption with a graphene/fullerene surface, all adsorbed complex shows enhancement in the Raman activity giving surface enhanced Raman spectra (SERS). This can be used for the detection of these drugs in a pharmacological or biological sample. Interestingly the graphene/fullerene drug molecular assembly shows enhanced biological activity when compared with individual drug molecules. Graphical abstract.

Spectral analysis and DFT investigation of some benzopyran analogues and their self-assemblies with graphene

Spectroscopic analysis and different quantum mechanical studies of four phramaceutically active flavanoid compounds, 5,7-dihydroxy-3-(4-hydroxyphenyl)-4H-chromen-4-one (genistein) (F1), 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-chromen-4-one (apigenin) (F2), 5,6,7-trihydroxy-2-phenyl-4H-chromen-4-one (baicalein) (F3) and 2-(3,4-dihydroxyphenyl)-3,7-dihydroxy-4H-chromen-4-one (fisetin) (F4) are reported in this manuscript using DFT/B3LYP/6-311++G(d,p) level of theory. Simulated IR spectrum of these compounds was compared with experimentally available data, and essential functional group assignments were made. NBO studies helped to study the various intramolecular electron delocalisation possible in the molecule. We also report the frontier orbital properties and other derived local energy descriptors which talks about the relative stability and reactivity of the compounds. The photovoltaic efficiency of the compounds was studied from the simulated electronic spectra. The compound was found to interact with graphene, to form molecular self-assembly. These self-assemblies showed tremendous enhancement in various physicochemical properties when compared with its constituents. Biological activity of the compounds were predicted using molecular docking studies.

Modelling the hygroscopic growth factors of aerosol material containing a large water-soluble organic fraction, collected at the Storm Peak Laboratory

The compositions of six aggregated aerosol samples from the Storm Peak Laboratory site have been comprehensively analysed (Hallar et al., 2013), focusing particularly on the large water-extractable organic fraction which consists of both high molecular weight organic compounds and a range of acids and sugar-alcohols. The contribution of the soluble organic fraction of atmospheric aerosols to their hygroscopicity is hard to quantify, largely because of the lack of a detailed knowledge of both composition and the thermodynamic properties of the functionally complex compounds and structures the fraction contains. In this work we: (i) develop a means of predicting the relative solubility of the compounds in the water-extractable organic material from the Storm Peak site, based upon what is known about their chemical composition; (ii) derive the probable soluble organic fraction from comparisons of model predictions with the measured hygroscopicity; (iii) test a model of the water uptake of the total aerosol (inorganic plus total water-extractable organic compounds). Using a novel UNIFAC-based method, different assignments of functional groups to the high molecular weight water soluble organic compounds (WSOC) were explored, together with their effects on calculated hygroscopic growth factors, constrained by the known molecular formulae and the double bond equivalents associated with each molecule. The possible group compositions were compared with the results of ultrahigh resolution mass spectrometry measurements of the organic material, which suggest large numbers of alcohol (–OH) and acid (–COOH) groups. A hygroscopicity index (HI) was developed. The measured hygroscopic growth is found to be consistent with a dissolution of the WSOC material that varies approximately linearly with RH, such that the dissolved fraction is about 0.45–0.85 at 90% relative humidity when ordering by HI, depending on the assumptions made. This relationship, if it also applies to other types of organic aerosol material, provides a simple approach to calculating both water uptake and CCN activity (and the κ parameter for hygroscopic growth). The hygroscopicity of the total aerosol was modelled using a modified Zdanovskii-Stokes-Robinson approach as the sum of that of the three analysed fractions: inorganic ions (predicted), individual organic acids and “sugar alcohols” (predicted), and the high molecular weight WSOC fraction (measured). The calculated growth factors broadly agree with the measurements, and validate the approach taken. The insights into the dissolution of the organic material seem likely to apply to other largely biogenic secondary organic aerosols from similar remote locations.

Growth and combined experimental and quantum chemical study of glycyl-L-Valine crystal

Glycyl-L-Valine (GLV) crystals were grown using distilled water as the solvent at room temperature by solution growth technique. Powder X-ray diffraction confirms the crystalline quality of GLV crystal. The molecular structure of GLV crystal was identified by 13C NMR spectral studies. The nonlinear optical (NLO) behavior of the crystal was found to be ∼4.3 times greater than that of potassium dihydrogen orthophosphate. FT-Raman and FT-IR spectra of the GLV were recorded and complete functional group assignment of the determined vibrational bands of GLV have been reported. Density functional theoretical method (DFT) was performed using B3LYP with the 6-311+G (d, p) basis set and the results were compared with the experimental values which confirm the intermolecular interactions responsible for the enhanced NLO activity of the molecule, as evident from NBO and Hirshfeld analyses. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. In addition, the molecular electrostatic potential (MEP) analysis, Mulliken atomic charges of the GLV molecule has been investigated using theoretical calculations.

Screening of Bifidobacterium strains with assignment of functional groups to bind with benzo[a]pyrene under food stress factors

The purpose of this study was to find the component of the Bifidobacterium cell wall more particularly the functional groups from peptidoglycan involved in the mechanism of binding with Benzo[a]pyrene. Additionally, the effect of different stress factors (acid, heat, alkaline, oxidative, osmotic, enzymatic, and detergent factors) on the functional group and the overall binding mechanism of Bifidobacterium with B[a]p were also evaluated. Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) were used to explain the binding mechanism of Bifidobacterium with B[a]p along with HPLC (high-performance liquid chromatography). The peptidoglycan-B[a]p complexes were highly stable after benzene washing. Peptidoglycan from Bifidobacterium infantis BY12 showed highest binding rate with B[a]p out of nine selected strains. FTIR spectra showed that the main functional groups involved in B[a]p binding were CO, OH and/or NH. FTIR spectrums along with SEM electrographs as a function of stress factors reveal that peptidoglycan structural integrity is important in B[a]p binding. Bifidobacterium longum subsp. infantis BY12 may be employed as a biological detoxification agent for the elimination of B[a]p from human diet and animal feed in the future.

Detection of Bioactive Compounds of Celosia argentea Using Fourier-transform Infrared Spectroscopic Profile and Evaluation of its Anti-fungal Activity

Celosia argentea is a smooth annual herb type plant and routinely used as leafy vegetable in the rainforest zone of Africa. In India and China, it is known as a troublesome weed. It is a herbaceous plant and is known for its very bright colors and traditional uses. This is plant of tropical origin; they grow best in full sunlight and should be placed in a well-drained area. The purpose of our research were analysis of the bioactive chemical compounds of selected medicinal plant of Celosia argentea using fourier transform infrared spectrophotometer analysis. Seven bioactive compounds were identified in the methanolic extract of Celosia argentea. The Fourier transform infrared spectrophotometer analysis of Celosia argentea proved the presence of functional group assignment Alkenes, Alkyl halides, Amide, and Alkane with Intensity 70.097 (Strong), 79.917 (Strong), 65.933 (Strong), 83.395 (Strong), 73.966 (Bending), 87.917 (Strong), 83.461 (Strong) and Peak (Wave number cm-ˡ) 667.37, 794.67, 1020.34, 1236.37, 1631.78, and 2854.65. In the current study, the anti-fungal activity of Celosia argentea methanolic extract was evaluated by determining the zone of inhibition against fungi. Celosia argentea was very highly active against Aspergillus fumigatus (4.98 ± 0.18).

In vitro Antimicrobial Activity of Methanolic Extract of Apium graveolens

The aims of our research were analysis of the secondary metabolite products and in vitro antibacterial and anti-fungal activities. Apium graveolens has been used as a food, and at various times both the whole plant and the seeds have been consumed as a medicine. The FTIR analysis of Apium graveolens leaves proved the presence of functional group assignment Alkyl halides, Amide, and Alkane with Intensity 75.578 (Strong), 87.413 (Strong), 86.158 (Strong), 84.616 (Bending), 88.087 (Strong), and Peak (Wave number cm1) 1020.34, 1238.30, 1317.38, 1608.63 and 2918.30. In the current study, the anti-microbial activity of Apium graveolens methanolic extract was highly against Klebsiella pneumoniae (4.27 ± 0.16). Apium graveolens was very highly active against A. terreus (5.01 ± 0.17).

Investigation of Bioactive Natural Compounds of Diplotaxis cespitosa Using FTIR Spectroscopic Profile and Evaluation of its Anti-Bacterial and Anti-Fungal Activity

Genus Diplotaxis (Brassicaceae) is represented by more than 30 species mainly distributed in the north Mediterranean. In the current study, the anti-microbial activity of Diplotaxis cespitosa methanolic extract was evaluated by determining the zone of inhibition against nine bacteria and eight fungi and yeast. Maximum zone formation was against Staphylococcus aureus (5.96 ± 0.19). Diplotaxis cespitosa was very highly active against Aspergillus flavus (6.34 ± 0.21). The FTIR analysis of Diplotaxis cespitosa proved the presence of functional group assignment Alkyl halides, Aromatic, Amide, and Alkane with Intensity 71.703 (Strong), 66.405 (Strong), 81.325 (Strong), 80.732 (Strong), 80.345 (Strong), 76.852 (Medium), 70.901 (Bending), 87.336 (Strong), 82.720 (Strong) and Peak (Wave number cm-ˡ) 1001.06, 1049.28, 1238.30, 1386.82, 1394.53, 1517.98, 1635.64, 2854.65, and 2926.01.

A Report on Growth And Spectroscopic Studies on The L-Tartaric Acid Doped Potassium Dihydrogen Phosphate Non-Linear Optical Single Crystals

In recent years study of non-linear optical (NLO) materials is gaining rapid momentum due to their needs in several device applications. Potassium Dihydrogen Phosphate (KDP) is a well-known NLO material, whose non-linearity is enhanced by doping with amino acids. In this present study, single crystal ofL- Tartaric acid doped potassium Dihydrogen phosphate (LTKDP) have been grown by slow evaporation method at room temperature. Good quality transparent crystals were obtained with 27-30 days. The crystallinity and cell parameters were characterized by X-ray diffraction analysis (XRD), the shifts in frequency assignments of various functional groups of KDP due to the addition of L-Tartaric acid was analysed by Fourier transform infrared (FTIR) and Fourier transform Raman spectroscopic studies. The dielectric constant and the dielectric loss of the single crystals were studied as a function of frequency. Kurtz- Perry power technique was employed to determine the Second Harmonic Generation (SHG) efficiency of LTKDP single crystal.

Examination of Early Functional Recovery After ACL Reconstruction: Functional Milestone Achievement and Self-Reported Function.

Background:Few studies have documented early functional recovery after anterior cruciate ligament (ACL) reconstruction.Purpose:To quantify the time to early functional milestone achievement and change in function over 12 weeks after ACL reconstruction and to identify demographic characteristic predictors of the outcomes.Study Design:Prospective, longitudinal, observational study.Level of Evidence:Level 4.Methods:A total of 182 patients (95 females, 87 males; mean ± SD age, 28 ± 12 years; mean ± SD body mass index [BMI], 25 ± 4 kg/m2) who received primary, unilateral, ACL reconstruction were included. Testing occurred before surgery as well as 1, 2, 4, 8, and 12 weeks postsurgery. Outcomes included demographic characteristics, self-reported functional milestone achievements and responses on the Short Musculoskeletal Function Assessment (SMFA) questionnaire. Time to functional milestone achievement was calculated, and patients were categorized into “faster” or “prolonged” recovery groups based on the median value. Longitudinal change in SMFA subscale scores (daily activities and mobility) as well as demographic predictors of functional recovery group assignment and postsurgical change in SMFA subscale scores were examined.Results:Median time for discontinuing narcotic pain medication was 9 days, while that for discontinuing crutches was 15 days. Time to return to work occurred at a median of 11 days, return to school at 7 days, and return to driving at 11 days. Both SMFA subscale scores significantly decreased (improved) over time, with the greatest change occurring between 1 and 4 weeks postsurgery. The demographic predictor of faster functional recovery for discontinuation of narcotic pain medication was surgery with allograft; those for return to work were higher age, male sex, decreasing BMI, and sedentary/light occupational demand; and those for return to driving were higher age, male sex, and surgery on the left side of the body.Conclusion:Functional recovery occurs rapidly over the first month after ACL reconstruction for most patients. Nonmodifiable demographic characteristics may influence recovery time for specific functional milestones.Clinical Relevance:Results can be used to counsel patients on early functional recovery after ACL reconstruction.